numerical investigation into the impact of co -water-rock...

Research ArticleNumerical Investigation into the Impact ofCO2-Water-Rock Interactions on CO2 Injectivity at the ShenhuaCCS Demonstration Project China

Guodong Yang1 Yilian Li1 Aleks Atrens2 Ying Yu1 and Yongsheng Wang3

1School of Environmental Studies China University of Geosciences Wuhan 430074 China2The Queensland Geothermal Energy Centre of Excellence School of Mechanical and Mining EngineeringThe University of Queensland St Lucia QLD 4072 Australia3China Shenhua Coal Liquefaction Co Ltd Ordos 017209 China

Correspondence should be addressed to Yilian Li yllicugeducn

Received 25 February 2017 Revised 17 May 2017 Accepted 28 June 2017 Published 3 August 2017

Academic Editor Tianfu Xu

Copyright copy 2017 Guodong Yang et alThis is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

A 100000 tyear demonstration project for carbon dioxide (CO2) capture and storage in the deep saline formations of the OrdosBasin China has been successfully completed Field observations suggested that the injectivity increased nearly tenfold afterCO2 injection commenced without substantial pressure build-up In order to evaluate whether this unique phenomenon couldbe attributed to geochemical changes reactive transport modeling was conducted to investigate CO2-water-rock interactions andchanges in porosity and permeability induced by CO2 injectionThe results indicated that using porosity-permeability relationshipsthat include tortuosity grain size and percolation porosity other than typical Kozeny-Carman porosity-permeability relationshipit is possible to explain the considerable injectivity increase as a consequence ofmineral dissolutionThesemodelsmight be justifiedin terms of selective dissolution along flow paths and by dissolution ormigration of plugging fines In terms of geochemical changesdolomite dissolution is the largest source of porosity increase Formation physical properties such as temperature pressure andbrine salinity were found to have modest effects on mineral dissolution and precipitation Results from this study could havepractical implications for a successful CO2 injection and enhanced oilgasgeothermal production in low-permeability formationspotentially providing a new basis for screening of storage sites and reservoirs

1 Introduction

Geological storage of carbon dioxide (CO2) in deep salineformations is widely considered as a significant method forreducing CO2 emissions in the atmosphere [1 2] Currentlya number of CO2 storage operations and demonstrationprojects (eg Sleipner Norway 1996 Weyburn Canada2000 Ketzin Germany 2006 Cranfield USA 2008 OtwayAustralia 2008) have been conducted around the world[3ndash7] The first pilot project of CO2 capture and storage(CCS) in China the Shenhua CCS demonstration projectsuccessfully completed its goal of injecting CO2 at a rateof 100000 tonsyear into the onshore saline aquifer in theOrdos Basin [8] The site of the Shenhua CCS project is inthe Chenjiacun village of Wulam Len town Ejinhoro county

about 45 km southeast of theOrdosCity InnerMongoliaTheOrdos Basin covers an area of 25 times 104 km2 is the secondlargest sedimentary basin in China and has low porosityand permeability typical of continental basins in China Deepsaline aquifers are widely distributed in the basin with largepotential for CO2 storage [9] The Shenhua CCS project useda single vertical well to inject CO2 into five reservoir-caprockassemblages deeper than 1576m the Liujiagou ShiqianfengShihezi Shanxi and Majiagou formations More than 80 ofthe total CO2 injected entered the first three formations [8]

During CO2 injection at the Shenhua CCS demonstra-tion a unique phenomenon was observed the injectionindex increased nearly tenfold from 4056m3hMPa in 2011to 40018m3hMPa in 2013 for the main injection layerwithout strong pressure build-up [10]This indicates that CO2

HindawiGeofluidsVolume 2017 Article ID 4278621 17 pageshttpsdoiorg10115520174278621

2 Geofluids

injectivity increases after injection started which is differentfrom earlier predictions [8]

For large-scale injection of CO2 into saline formationsCO2 injectivity is a key technical and economic issue ofconcern Previous studies and applications show that CO2injectivity can be affected by the following mechanisms (1)pressure build-up due to massive and continuous CO2 injec-tion (2) dry-out of the near-well zone due to evaporation ofH2O into unsaturated CO2 (3) CO2-water-rock interactionsinduced by the injection of CO2 (Bacci et al 2011) [11ndash13]Among these processes CO2-water-rock interactions couldalter the rock matrix and potentially lead to porosity andpermeability changes in the near-well zone [14ndash17] which isof particular importance for CO2 injectivity

Laboratory experiments related to CO2 injection intosandstone and carbonate rocks have been reported in theprevious studies [15 18ndash22] These experiments indicate thatCO2-water-rock interactions can have a substantial effect onporosity and permeability depending on fluid compositionrockmineralogy and subsurface thermodynamic conditionsThey found that carbonate dissolution processes seem to bethemain cause of permeability increases and promote a rapidspreading of the reaction front in short time scales

Reactive transport modeling has been previously usedto investigate geochemical reactions and their effects onpermeability and porosity evolution [14 15 23ndash26] Andreet al [14] simulated CO2 storage in the carbonate-richDogger aquifer in the Paris Basin (France) using the reactivetransport simulator TOUGHREACT They found that theporosity in the near-well zone increased significantly dueto mineral dissolution This was in accordance with thereactive flow-through experimental study by Luquot andGouze [15] for the same basin Some studies [25 26] alsoreported that geochemical reactions dissolved the host rockincreasing porosity and permeability thereby affecting fluidflow through reactive transportmodeling On the other handIzgec et al [23] found that CO2 injection into carbonateaquifers simulated using CMGrsquos STARS could result inpermeability reduction as well as improvement dependingon the balance between mineral dissolution and precipita-tion Furthermore Sbai and Azaroual [24] found that CO2injection could in some circumstances cause particulates toclog reservoir pores leading to a permeability reduction andinjectivity decline near the injection well

Laboratory experiments imaging characterization andnumerical modeling have previously been combined todescribe mineral alteration and associated reactive transportprocesses and mechanisms in porous media induced byCO2 injection (Bacci et al 2011) [16 27 28] Those studiesfocused on pore- or continuum-scale transport and reac-tion processes and indicated that CO2 injectivity increasesfrom dissolution of both carbonate and silicate minerals(especially feldspars) They also confirmed the rapid reactionkinetics of carbonate minerals compared to silicate mineralsAmong these research approaches numerical modeling is anexcellent technique in which CO2 injection and geochemicalperformance can bemodeled at different temporal and spatialscales

In general previous studies reveal that CO2-water-rockinteractions induce mineral dissolution and precipitationwhich can consequently change the porosity andpermeabilityof the subsurface matrix and thus affect the CO2 injectivityand overall storage capacity The trend and magnitude ofchange in porosity and permeability are highly reservoirspecific and depend on reservoir properties which are relatedto particle sizes brine composition and as well the thermo-dynamic conditions

Analyses of geohydrological mechanical thermal andgeochemical processes involved in Shenhua CCS project havebeen reported [29ndash33]However few of these have focused onthe considerable CO2 injectivity increase during CO2 injec-tion period Liu et al [33] examined this unique phenomenonthrough numerical simulation and concluded that it could beexplained through heterogeneities in reservoir permeabilityHowever their approach did not consider the possible role ofCO2-water-rock interactions on CO2 injectivity

In this study we applied a 2D radial injectionmodel usingthe reactive transport code TOUGHREACT to investigatethe effect of CO2-water-rock geochemical reactions on CO2injectivity through the evolution of the formation porosityand permeability at the Shenhua CCS site We focus onLiujiagou Shiqianfeng and Shihezi formations which are thethree main formations that sequestrate more than 90 oftotal CO2 injected The goal is to determine the key mech-anisms controlling the CO2-water-rock interactions duringCO2 injection particularly focusing on investigation of thereasons for CO2 injectivity improvement in the ShenhuaCCS project Moreover we examined the impact of variousparameters on mineral dissolutionprecipitation as well asrelevant porosity and permeability changes and comparedthe simulation results with available experimental dataUnderstanding of these mechanisms could have importantpractical implications for a successful CO2 injection andstorage operation in low-permeability formations providinga new basis for screening of the storage sites and reservoirsand assessing CO2 injectivity from a geochemical point ofview

2 Modeling Approach

21 Numerical Tool The simulations presented in thisstudy were carried out using the reactive transport codeTOUGHREACT [34 35] which introduces reactive geo-chemistry into the multiphase fluid and heat flow codeTOUGH2 V2 [36] A fluid property module ECO2N [37]was used to describe isothermal or nonisothermalmultiphaseflow in H2O-NaCl-CO2 system under conditions typicallyencountered in saline aquifers of interest for CO2 seques-tration (31∘C le 119879 le 110∘C 738MPa lt 119875 le 60MPa)TOUGHREACT is a thermal-physical-chemical code appli-cable to one- two- or three-dimensional geologic systemswith physical and chemical heterogeneity The numericalmethod for fluid flow and chemical transport simulationis based on the integral finite difference (IFD) methodfor space discretization The system of chemical reactionequations is solved on a grid-block basis by Newton-Raphsoniteration Thermodynamic data used in the simulations were

Geofluids 3

(a)

QCO2 = 317 kgs

100 m

02 m 10000 m

Injection well

Impermeable caprock

Impermeable bedrock

Sandstone formation

01 Mtyearasymp

(b)

Figure 1 (a) Injection well (Zhongshenzhu 1) at the Shenhua CCS site and (b) schematic diagram of the 2D model

taken from the EQ36 database [38] which derived usingSUPCRT92 Local equilibrium constants and kinetic ratesused in TOUGHREACT refer to Xu et al [35]

Porosity changes in the matrix are directly tied to thevolume changes as a result of mineral dissolution and precip-itation The porosity of the reservoir in the TOUGHREACTcode is calculated by

120601 = 1 minus119886119887

sum119887=1

f r119887 minus f r119906 (1)

where 119886119887 is the number ofminerals f r119887 is the volume fractionofmineral 119887 in the rock (119881mineral119881medium including porosity)and fr119906 is the volume fraction of nonreactive rock

Reservoir permeability changes are calculated fromchanges in porosity using ratios of permeabilities as per theKozeny-Carman grain model [35] as follows

119896 = 119896119894 (1 minus 120601119894)2(1 minus 120601)2 (

120601120601119894)3

(2)

where 119896119894 is the initial permeability 120601 and 120601119894 are current andinitial porosity respectively

Full details on numerical methods are given in [34 35]

22 Model Description A two-dimensional (2D) radialmodel is employed as a conceptual framework to study theCO2-water-rock interactions on CO2 injectivity in the threemain formations (Liujiagou Shiqianfeng and Shihezi) atthe Shenhua CCS demonstration project site (Figure 1) The2D homogeneous model represents a 100m thick sandstonereservoir with a radial extent of 10 km sufficiently large toensure that boundary pressure conditions are maintainedconstant at initial values that is equivalent to an infinitelyacting system Other authors have used similar approxima-tions in previous studies (Bacci et al 2011) [35 39] The gridis composed of 4010 cocentered cell elements The radius ofthe first cell containing the injection well is 02m Away from

the injection well 200 grid cells are considered between 02and 1000m 100 grid cells between 1000m and 3000m and100 grid cells between 3000m and 10 km In each intervalthe radius of the cells follows a logarithmic progressionThe vertical discretization is achieved by a division of thereservoir into 10 layers with a constant spacing of 10m Thebedrock and caprock are assumed to be impermeable no-flowboundaries

CO2 is injected into the reservoir at a constant flow rate of317 kgs (corresponding to 01Mtyear) at the bottom 4 layersof the injection well uniformly for 30 years The physicalproperties used to model the three formations (which havedepth ranges from 1576m to 2232m) at the Shenhua CCSsite are from previous works [8 40] and are summarizedin Table 1 The initial pressure is in hydrostatic equilibriumdetermined using the model and the temperature of thethree formations is fixed at 55∘C 62∘C and 67∘C respectivelyThe porosity and permeability of the three formations areobtained from well log data and permeabilities are assumedto be isotropic Pore compressibility of the formations is setto be 45 times 10minus10 The capillary pressure and liquid relativepermeability are computed by van Genuchten [41] and gasrelative permeability is calculated after Corey [42] Differentscenarios have been simulated to determine the differentmechanisms of CO2-water-rock interactions

23 Mineral Composition The initial rock mineral compo-sition was derived from the laboratory analysis as describedin [8 43ndash45] The Liujiagou formation is characterized asfeldspar sandstone and lithic arkose It consists mainly ofquartz alkali feldspar plagioclase the multilayer of chloriteand smectite illite and kaolinite The Shiqianfeng formationconsists mainly of feldspar rich sandstone and lithic arkosewhich is mainly composed of quartz feldspars calcite andsmall amount of clay minerals (illite and smectite) Felds-pathic quartz sandstone and feldspathic lithic sandstone arethe main rock type of the Shihezi formation It consistsmainly of quartz with some clayminerals (illite and smectite)

4 Geofluids

Table 1 Hydrogeological parameters of the formations used in this study

Parameter Liujiagou formation Shiqianfeng formation Shihezi formationPermeability (m2) 281 times 10minus15 658 times 10minus15 599 times 10minus15

Porosity 010 0129 0126Pore compressibility (Paminus1) 45 times 10minus10 45 times 10minus10 45 times 10minus10

Rock grain density (kgm3) 2600 2600 2600Formation heat conductivity (Wm ∘C) 251 251 251Rock grain specific heat (Jkg ∘C) 920 920 920Temperature (∘C) 55 62 67Pressure (MPa) 16 189 21Salinity (wt) 6 3 09Relative permeability modelLiquid [41]

119896119903119897 = radic119878lowast 1 minus (1 minus [119878lowast]1120582)1205822 119878lowast = (119878119897 minus 119878119897119903)(1 minus 119878119897119903)

Residual liquid saturation 119878119897119903 = 030Exponent 120582 = 0457Gas [42]

119896119903119892 = (1 minus 119878)2 (1 minus 1198782) 119878 = (119878119897 minus 119878119897119903)(1 minus 119878119897119903 minus 119878119892119903)

Residual gas saturation 119878119892119903 = 005Exponent capillary pressure model [41] 120582 = 0457119875cap = minus1198750 ([119878lowast]minus1120582 minus 1)1minus120582 119878lowast = (119878119897 minus 119878119897119903)

(1 minus 119878119897119903)Residual liquid saturation 119878119897119903 = 000Exponent 120582 = 0457Strength coefficient 1198750 = 1961 kPa

carbonates (calcite and dolomite) and plagioclase It shouldbe noted that alkali feldspar is represented as K-feldspar pla-gioclase is represented as an ideal solid solution of oligoclaseand smectite is divided into Na-smectite and Ca-smectiteequally by volume fraction referring to previous studies [46ndash48] The detailed mineral composition is given in Table 2

Simulation results can be influenced profoundly by thechoice of secondary mineral assemblage Almost all possiblesecondaryminerals are considered in the simulations accord-ing to previous studies [35 49]

24 Water Geochemistry The main ions contained in porewater within the three formations are Na+ Ca2+ and Clminushowever the total dissolved solids (TDS) content variessubstantially The Liujiagou formation water is high salinitywith a TDS content of about 56000mgL The TDS contentof Shiqianfeng formation water is 31200mgL and the TDScontent of Shihezi formation water is 9390mgL [44 4550] Prior to simulating reactive transport batch geochem-ical modeling of water-rock interaction was performed toequilibrate the initial formation water composition with theprimary formationminerals (Table 2) at the reservoir temper-ature and CO2 partial pressure The background CO2 partialpressure is chosen to match the measured pH according toXu et al [51] The resulting water chemistry of the threeformations (Table 3) is used as the initial conditions for thereactive transport simulation of CO2 injection

3 Results and Discussion

31 Influence of Porosity and Permeability Changes on CO2Injectivity Injectivity 119869 is the flow rate of CO2 achievedfor a particular pressure difference between the injectionwell and the reservoir It is linearly proportional to reservoirpermeability as given by

119869 = 119902Δ119875 prop 2120587119896ℎ

120583 ln (119903119903119903119908) (3)

where 119902 is the volumetric flow rate of injected CO2 ΔP is apressure differential between injection pressure and reservoirpressure ℎ is the vertical thickness of the reservoir 120583 is thefluid viscosity and 119903 is the radial distance with subscriptsdenoting the well-reservoir interface and boundary of thereservoir Permeability changes close to the injection wellhave a comparatively larger effect than permeability changesin distant regions of the reservoir due to the logarithm ofradial distance in the denominator The precise effect oflocalized changes in permeability can be estimated using anaverage weighted by the logarithm of the radial distance asdefined by

119869119869119894 =

119896sum119899119894 119896119894 ln (119903119894119903119894minus1) (4)

For a preliminary analysis of the potential effect ofpermeability changes it is not necessary to solve (4) precisely

Geofluids 5

Table 2 Mineralogical compositions of the three formations initial mineral volume fractions introduced in the model and possiblesecondary mineral phases used in the simulations

Mineral Chemical composition Volume fraction ()Liujiagou Shiqianfeng Shihezi

PrimaryQuartz SiO2 27 65 66K-feldspar KAlSi3O8 14 9 mdashOligoclase Ca02Na08Al12Si28O8 24 16 6Calcite CaCO3 mdash 3 3Dolomite CaMg(CO3)2 mdash mdash 3Illite K06Mg025Al18(Al05Si35O10)(OH)2 17 45 185Kaolinite Al2Si2O5(OH)4 6 mdash mdashChlorite Mg25Fe25Al2Si3O10(OH)8 85 mdash mdashNa-smectite Na0290Mg026Al177Si397O10(OH)2 175 125 175Ca-smectite Ca0145Mg026Al177Si397O10(OH)2 175 125 175Total 100 100 100SecondaryMagnesite MgCO3Albitesimlow NaAlSi3O8Siderite FeCO3Ankerite CaMg03Fe07(CO3)2Dawsonite NaAlCO3(OH)2Hematite Fe2O3Halite NaClAnhydrite CaSO4

Table 3 Initial component concentrations of the formation waterin the three formations

Component Concentration (molkg H2O)Liujiagou Shiqianfeng Shihezi

Na+ 109 419 times 10minus1 197 times 10minus1

Ca2+ 132 times 10minus2 566 times 10minus2 270 times 10minus5

Mg2+ 709 times 10minus7 559 times 10minus13 225 times 10minus5

K+ 684 times 10minus5 182 times 10minus3 287 times 10minus5

Fe2+ 102 times 10minus4 125 times 10minus5 952 times 10minus11

Clminus 112 506 times 10minus1 150 times 10minus1

SO42minus 393 times 10minus4 185 times 10minus2 226 times 10minus7

HCO3minus 177 times 10minus3 650 times 10minus4 457 times 10minus2

AlO2minus 132 times 10minus8 277 times 10minus8 759 times 10minus8

SiO2 (aq) 515 times 10minus4 589 times 10minus4 663 times 10minus4

pH 703 668 792Temperature 55∘C 62∘C 67∘C

the order of magnitude of the effect on injectivity can beassessed by assuming a uniform change in permeability Onthat basis injectivity increases linearlywith permeability witha gradient of unity The maximum permeability increases of032 040 and 139 for the three reservoirs would causean identical increase in CO2 injectivity Consequently thepermeability change estimated using (2) and (3) is insufficientto explain the obvious increase in injectivity observed duringthe Shenhua CCS project

However this result relies on the use of the Kozeny-Carman grain model (2) as an estimate of permeabilitychanges in response to porosity change frommineral precipi-tationdissolution Implicit in this model are the assumptionsthat tortuosity and mineral grain size remain constant asporosity changes which may not be the case Furthermorethe Kozeny-Carman model excludes the possibility of apercolation limit to permeability that is a minimumporositybelow which permeability is zero due to a lack of hydraulicconnectivity between pores Alternative forms of the Kozeny-Carman model have been proposed which account for thesefactors [52] such as

119896 = 119896119894 1198892

119889119894212059111989421205912

(1 minus 120601119894 + 120601119901)2(1 minus 120601 + 120601119901)2

(120601 minus 120601119901)3(120601119894 minus 120601119901)3

(5)

where 119889 represents mineral grain size 120591 is tortuosity and 120601119901is the percolation porosity for the reservoir rock From (5) ifthe CO2-water-rock interaction-induced mineral dissolutioncauses grain size increase or tortuosity reduction it couldresult in larger permeability increase than calculated from (2)

Grain size does not anticipate increase substantiallyPercolation porosity is estimated to typically be 1ndash3 [52]which is insufficient to explain increases in injectivity apercolation porosity of 3 would lead to maximum perme-ability increases of 045 050 and 187 for the threereservoirs However tortuosity has been reported to varywidely at fixed porosity for similar rock or other porousmedium samples [53] A large decrease in tortuosity would

6 Geofluids

cause a very substantial difference in permeability (eg ahalving of tortuosity would increase permeability by a factorof four) A large decrease in tortuosity can be explainedat least in theory by mineral precipitation-dissolution thatselectively occurs in relation to major fluid flow paths Thatis if dissolution predominates along larger and more directflow paths and precipitation mainly occurs in pores that arenot part of flow pathways small changes in total porositymaylead to substantial increase in tortuosity and consequentlypermeability Furthermore it is possible that tortuosity can bedecreased by the removal of fine particulates that plug bridgeor impinge existing or potential fluid flow paths Only smallamounts of dissolutionmay be necessary to dislodge fines andallow them to settle out of fluid flow

These possible explanations provide a conceptual frame-work which could explain injectivity increases in termsof CO2-water-rock-interaction-induced mineral dissolutionand precipitation Further research would be needed toevaluate whether they are appropriate to apply to this reser-voir system In particular flow models incorporating finesmigration and the effect ofmechanical forces on precipitationand dissolution reactions as well as empirical studies usingreservoir core samples may provide insights into possiblegeological mechanisms for CO2 injectivity increase Thisfurther work may assist in differentiating between geochem-ical changes and permeability heterogeneity as competingexplanations for the observed CO2 injectivity increase

32 Analysis of Mineral DissolutionPrecipitation on PorosityChanges The amount of dissolution and precipitation ofminerals induced by CO2-water-rock interactions deter-mines porosity change In order to investigate this processclarify the key minerals leading to porosity changes and ana-lyze the differences between different mineral assemblagesof the Liujiagou Shiqianfeng and Shihezi formations weinvestigate the distribution of changes in mineral volumefraction and concentrations of major aqueous species forthese three formations along the horizontal direction at thedepth of minus75m after 30 years of CO2 injection

The change in mineral composition and major aque-ous species as a function of CO2-water-rock interaction-induceddissolution andprecipitation for different formationscan be seen in Figure 2 Figure 2(a) shows the horizontaldistribution of changes in main mineral volume fractionand porosity for Liujiagou formation after 30 years of CO2injection It can be seen that porosity changes throughoutthe simulation are distinctly tied to the mineral dissolu-tion and precipitation The spatial distribution of mineralalteration varies in different regions Mineral dissolutionand precipitation are most substantial in zone II becausethere is sufficient aqueous CO2 to decrease pH to values aslow as 50 perturbing the equilibrium state of the systemThis is consistent with changes in concentrations of majoraqueous species (Figure 2(b)) The main dissolved mineralsare oligoclase chlorite K-feldspar and kaolinite with theoligoclase dissolution providing the main source of volumefraction reduction in agreement with minerals behavior inlaboratory experiments [45] The main precipitated mineralsare Na-smectite Ca-smectite illite and siderite consuming

Ca2+ and Mg2+ provided by the dissolution of oligoclase andchlorite The net volume fraction change of minerals is areduction resulting in porosity increase

The resulting porosity changes of the Shiqianfeng forma-tion are explored in Figure 2(c) where the volume fractionchanges of minerals versus radial distance are shown after30 years of CO2 injection The injection of CO2 displacesthe liquid flow away from the injection well but some liquidflow reverses due to capillary-drive providing water forCO2-water-rock interactions The porosity increases slightlyin zone I which can be explained by the large amountof calcite dissolution relative to the anhydrite precipitationThis is consistent with the increase of Ca2+ concentration(Figure 2(d)) However this effect is reduced in the regionapproximately 30m away from the well due tomanymineralsprecipitating In zone II oligoclase illite and calcite vol-umes decreased relative to initial conditions while kaolinitequartz dawsonite K-feldspar Na-smectite and Ca-smectitevolumes increased Overall the most important contributorto net volume change caused by precipitation and dissolutionwas oligoclase dissolutionThere was no noticeable change inporosity in zone III because CO2 has not reached that regionof the reservoir

As shown in Figure 2(e) there is a distinct difference inthe mineral alterations between the Shihezi formation andthe other two formations particularly in terms of variation indolomite and calcite In the Shihezi formation as the volumefraction of dolomite decreases (6) the volume fraction ofcalcite increasesThis is also demonstrated by the experimen-tal study [44] The effect of dolomite dissolution and calciteprecipitation is substantial in zone I and determines thechange in porosityThe changes in this zone can be explainedby liquid flow reversal into zone I due to capillary-drivecombinedwith the high reactivity of dolomite resulting in fastCO2-water-rock interactions It can be inferred that the disso-lution of dolomite provides Ca2+ for calcite precipitation ((6)-(7)) with Ca2+ making no significant changes (Figure 2(f))In zone II the dolomite dissolution and calcite precipitationare also substantial although the porosity change is alsoaltered by oligoclase dissolution and Na-smectite and Ca-smectite precipitation The overall effect is a reduction innet mineral volume fraction that leads to porosity increaseOligoclase dissolution also occurs in zone III mainly dueto precipitation of Na-smectite and Ca-smectite ((8)-(9))consuming Ca2+ and Na+ and consequently promoting thedissolution of oligoclase (10)

CaMg (CO3)2 (dolomite) + 2H+ 997888rarr Ca2+ +Mg2+

+ 2HCO3minus

(6)

Ca2+ +HCO3minus larrrarr CaCO3 (calcite) +H+ (7)

026Mg2+ + 029Na+ + 177Al (OH)3 + 397H4SiO4997888rarr Na0290Mg026Al177Si397O10 (OH)2sdot (Na minus smectite) + 081H+ + 919H2O

(8)

Geofluids 7

Zone IIZone I Zone III

KaoliniteIlliteOligoclaseNa-smectite

K-feldsparChloriteCa-smectiteSiderite-2

minus00008

minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

01000

01001

Poro

sityPorosity

1 10 100 100001 10000

Radial distance (m)

(a)

pH

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

Ca2+

Mg2+

Fe2+

SiO2 (aq)

CO2 (aq)


0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(b)


IlliteKaolinite

AnhydriteCalcite

Oligoclase

Na-smectiteK-feldsparCa-smectiteQuartzDawsonite

minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

als v

olum

e fra

ctio

n

Porosity01290

01291

Poro

sity

1 10 10000100010001

Radial distance (m)

(c)

pH

Ca2+Fe2+

SiO2 (aq)CO2 (aq)


1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10Th

e con

cent

ratio

n of

aque

ous s

peci

es

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(d)


CalciteOligoclaseDolomiteNa-smectite

Ca-smectite

Porosity0126201260

01264

Poro

sity

1 10 10000100010001

Radial distance (m)

minus00010

minus00008

minus00006

minus00004

minus00002

00000

00002

00004

00006

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

(e)

pH

Ca2+

Mg2+

SiO2 (aq)CO2 (aq)

Zone IIZone I

Zone III

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(f)

Figure 2 The horizontal distribution of changes in main mineral volume fraction porosity and concentrations of major aqueous speciesand pH for Liujiagou formation (a b) Shiqianfeng formation (c d) and Shihezi formation (e f) along the horizontal direction at the depthof minus75m after 30 years of CO2 injection

8 Geofluids

3 10 yryr 30 yr Oligoclase

minus00001minus00002minus00003minus00004minus00005minus00006minus00007

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)

200 400 600 800 10000Radial distance (m)

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


(a)

minus00001minus000013minus000016

Calcite

Oligoclase


minus80

minus60

minus40

minus20

0

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus7E minus 05

minus4E minus 05

minus1E minus 05

(b)

Dolomite

minus000019minus000033minus000047minus000061minus000075minus000089minus000103minus000117

minus80

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Dep

th fr

om th

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(m)


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00 0

Dep

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om th

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(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yrminus5E minus 05

(c)

Figure 3 Temporal and spatial evolution of the keyminerals volume fraction in the three formations ((a) Liujiagou formation (b) Shiqianfengformation (c) Shihezi formation)

026Mg2+ + 0145Ca2+ + 177Al (OH)3+ 397H4SiO4997888rarr Ca0145Mg026Al177Si397O10 (OH)2sdot (Ca minus smectite) + 081H+ + 919H2O

(9)

CaNa4Al6Si14O40 (Oligoclase) + 6H+ + 34H2O997888rarr Ca2+ + 4Na+ + 6Al (OH)3 + 14H4SiO4

(10)

The temporal and spatial evolution of the volume fractionof key minerals within the three formations is shown inFigure 3 By analyzing the porosity changes and mineralalteration in Figures 2 and 3 it can be seen that the keyminerals affecting porosity in the near-well region (zone I) arecalcite and dolomite In zone II the dissolution of oligoclaseand dolomite plays the key role in porosity increases which isconsistent with the phenomenon observed by Hao et al [16]through the study of CO2-induced dissolution processes oflow-permeability carbonate reservoirs It can be concludedthat oligoclase dolomite and calcite are the keyminerals that

Geofluids 9

Table 4 Summary of the simulation cases

Simulationscenarios Variable changed Alternative value

Case 1 Dolomite volume fraction()

0Case 2 15Case 3 Calcite volume fraction () 0Case 4 15Case 5 Oligoclase volume fraction

()0

Case 6 15Case 7 Temperature (∘C) 50Case 8 80Case 9 Pressure (MPa) 10Case 10 30Case 11

Salinity (wt)009

Case 12 9Case 13 15

affect porosity increases in the Shenhua CCS demonstrationproject during CO2 injection

These results indicate the importance of localizedmineraldissolution during CO2-water-rock interactions which canlead to a large increase in the volume of void space therebyincreasing the porosity and permeability of the reservoirand potentially CO2 injectivity via mechanisms previouslydiscussed

33 Analysis of Factors Affecting Porosity Change Min-eral composition temperature pressure and salinity mayeach influence CO2-water-rock interactions (mineral disso-lutionprecipitation) thereby affecting porosity and perme-ability changes In order to investigate the influence of thesefactors an additional 13 simulation cases were analyzed eachvarying one factor relative to a base case for the Shiheziformation (Table 4) It should be noted that the mineralcomposition (especially dolomite calcite and oligoclase) andformation physical properties (eg temperature pressureand brine salinity) are the key difference between the differentformations Therefore a series of analyses are conductedto assess how the porosity and permeability changes andmineral alteration are affected by these parameters

331 Impacts of Key Minerals Dolomite is one of the keyprimary minerals in the system Figures 4(a) and 4(b) showthe difference in the porosity change andmineral alteration ifthe reservoir contains larger or smaller amounts of dolomiteIt can be seen that the maximum porosity is above 1261in the CO2 plume when there is no dolomite in the systemThemaximum porosity increases to 12645 when the initialvolume fraction of dolomite is 3 However when the initialvolume fraction of dolomite is 15 porosity is not markedlyincreased and in fact porosity changes in zone II coincidewith results for a dolomite volume fraction of 3As dolomitecontent increases in the near-well region (zone I) it hasless effect on porosity change this is because reactivity islimited by lack of water (due to evaporation of water into the

free CO2 phase) and excessive initial mineral (ie dolomitesupersaturation) This was also observed in a flow-throughexperiment performed by Tutolo et al [22]

The complex effect of dolomite on the porosity resultsfrom the different behavior of minerals alteration inducedvariation in dolomite content As shown in Figures 4(b) and4(c) when there is no dolomite in the system the mineralsand major aqueous species show very different behaviorcompared with the base case Under those circumstancescalcite is dissolved rather than precipitated in zone I and zoneII and oligoclase mainly dissolves in zone II while there isno Mg2+ provided by dolomite Some kaolinite and quartzprecipitated which is also very different from the base case

The overall effect of increased dolomite volume fraction isa reduction in netmineral volume fraction leading to aminorporosity increase When dolomite is present (and conse-quently Ca2+ and Mg2+) dedolomitization occurs dolomitetransforms into calcite This result agrees well with Yan andZhangrsquos study [54] It occurs because the change in Gibbs freeenergy (Δ119866) for dolomite dissolution is smaller than that forcalcite dissolution that is the required energy for dolomitedissolution is less than that for calcite [27 55] Consequentlythe dissolution of dolomite occurs more readily than that ofcalcite Furthermore the presence of dolomite can promotethe precipitation of Na-smectite and Ca-smectite and thedissolution of oligoclase outside the CO2 plume

Compared with dolomite calcite has minimal effects onthe mineral alteration porosity and major aqueous specieschanges in the system as shown in Figures 4(d)ndash4(f) Itshould be noted that the black line representing 3 volumefraction calcite coincides with the blue line representing 15calciteWhen calcite is absent in the primaryminerals calciteis still precipitated in the system due to the increase inCa2+ supplied by dolomite dissolution (dedolomitization)mentioned above Only when dolomite is absent can calcitedissolve to make a contribution to the porosity increase(Figures 2(c) and 4(b))

Figures 4(g)ndash4(i) show the changes in major aqueousspecies porosity and relevant mineral alteration with respectto radial distance for different initial oligoclase contentTheseresults indicate that oligoclase also plays an important rolein porosity and permeability changes (Figure 4(g)) It can beseen that the greater the oligoclase content the smaller theporosity increases and the concentration ofMg2+ supplied bydolomite which is mainly because oligoclase can inhibit thedissolution of dolomite (Figure 4(h)) This further suggeststhat dolomite is an important mineral for formation porosityincreases and CO2 injectivity improvement

332 Impacts of Physical Parameters In order to investigatethe impact of physical parameters temperature pressure andsalinity we have used the Shihezi formation as the base caseto vary one factor to obtain the temperature pressure andsalinity targeted allowing more comparable consistent andmaking sense results The initial temperature and pressure ofthe Shihezi formation are 67∘C and 21MPa and the variationof temperature is 50∘C (Case 7) and 80∘C (Case 8) and thepressure is 10MPa (Case 9) and 30MPa (Case 10) The initial

10 Geofluids


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Dolomite_0Dolomite_3Dolomite_15

(a)

Zone IIZone IZone III

100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

e

Kaolinite

Calcite

Oligoclase

Na-smectiteCa-smectite

Quartz

Dolomite


frac

tion

(b)


0

2

4

6

8

10

pH

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

Ca2+

SiO2(aq)

CO2 (aq) Mg2+


HCO3minus

(c)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Calcite_0Calcite_3Calcite_15

(d)

Zone II

Zone I Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(e)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(f)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Oligoclase_15Oligoclase_6Oligoclase_0

(g)

Zone II

Zone I

Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

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minus00003

00000

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00006

Chan

ges i

n m

iner

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olum

efr

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(h)


0

2

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100 100001 1 1000010

Radial distance (m)

The c

once

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tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(i)

Figure 4 The horizontal distribution of changes in porosity mineral volume fraction and concentrations of major aqueous species and pHfor different amounts of dolomite (a b and c) calcite (d e and f) and oligoclase (g h and i) at the depth of minus75m after 30 years of CO2injection

water salinity of the Shihezi formation is 09 wt dissolvedNaCl and it is evaporated to 9 (Case 12) and 15 (Case 13) wtdissolvedNaCl and diluted to 009wt dissolvedNaCl (Case11) to evaluate the salinity effect as can be seen in Table 4

Temperature Figure 5(a) shows that the porosity change at thereservoir temperature of 67∘C is larger than at the tempera-ture of 50∘C and 80∘C indicating that the changes in porosityincrease first and then decrease with increasing reservoirtemperature in zone I and zone II with the maximum value

occurring between 50∘C and 80∘C This is attributed to thechanges in mineral volume fraction that the dissolution ofdolomite increases first and then decreases with increasingtemperature in zone I and zone II (Figure 5(b)) which is con-sistent with the study conducted by Yan et al [56] Althoughthe dissolution of oligoclase increases with increasing tem-perature the precipitation of Na-smectite and Ca-smectiteincreases correspondingly in zone II such that there is nearlyno net contribution to porosity increases Porosity increaseswith larger temperatures in zone III without CO2 resulting

Geofluids 11

100 100001 1 1000010

Radial distance (m)

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Poro

sity Zone IIZone I Zone III

T_50∘CT_67∘CT_80∘C

(a)


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minus00012

minus00009

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00000

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Chan

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Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite

T_50∘CT_67∘CT_80∘C

(b)

100 100001 1 1000010

Radial distance (m)

The c

once

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s (m

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1Eminus4

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001

01

10

1pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


0246810

pH

T_50∘CT_67∘CT_80∘C

HCO3minus

(c)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

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01265

Poro

sity

Zone II

Zone I

Zone III

P_10 MPaP_21 MPaP_30 MPa

(d)


100 100001 1 1000010

Radial distance (m)

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00000

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Chan

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Calcite

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Dolomite

Ca-smectite


(e)


pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

100 100001 1 1000010

Radial distance (m)

The c

once

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1Eminus4

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HCO3minus


(f)

100 100001 1 1000010

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sity

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Zone III

Salinity_09Salinity_9Salinity_15

(g)


100 100001 1 1000010

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minus00012

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minus00003

00000

00003

00006

Chan

ges i

n m

iner

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olum

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n Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(h)


100 100001 1 1000010

Radial distance (m)

The c

once

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tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

HCO3minus


(i)

Figure 5 The horizontal distribution of changes in porosity mineral volume fraction and concentrations of major aqueous species and pHfor different temperature (a b and c) pressure (d e and f) and salinity (g h and i)

from the dissolution of oligoclase The effect of temperatureon the horizontal distribution of changes in major aqueousspecies is shown in Figure 5(c) which agrees well with themineral alteration It can be concluded that temperature hasa large effect on mineral dissolution and precipitation as wellas consequent porosity and permeability changes

Pressure The impact of pressure on the horizontal distri-bution of changes in porosity mineral volume fractionand major aqueous species is shown in Figures 5(d)ndash5(f)It can be seen that the change in porosity increases withincreasing pressure from 10MPa to 30MPa (Figure 5(d))

However the impact of pressure on the precipitation anddissolution of different minerals varies This also leads tothe complex behavior of major aqueous species (Figure 5(f))The dissolution of dolomite increases with pressure resultingin corresponding calcite precipitation while no effect ofpressure on oligoclase dissolution is observed within thepressure range investigated This also supports the ideathat the porosity increases resulted from the key carbonatemineral-dolomite dissolution

Salinity The effect of salinity on porosity was evaluatedby evaporating the initial water of the Shihezi formation

12 Geofluids

Porosity010011010009010007010005010003010001

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(m)


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Porosity012915012912501291012907501290501290250129

0

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(m)


minus80

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epth

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)


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(m)


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(b)

PorosityPorosity012648012642012636012630126240126180126120126060126

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

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(m)


minus80

minus60

minus40

minus20

0

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th fr

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(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)

Figure 6 The evolution of porosity in the three formations ((a) Liujiagou formation (b) Shiqianfeng formation (c) Shihezi formation)

(09 wt dissolvedNaCl) to increase salinity to 9 and 15wtdissolved NaCl and diluting the initial water to decrease thesalinity to 009wt dissolved NaCl As shown in Figure 5(g)the changes in porosity increase with salinity between 09and 15wt dissolved NaCl It can be inferred that the overalleffect of salinity is a reduction in netmineral volume fractionFigures 5(h) and 5(i) show the horizontal distribution ofchanges in mineral volume fraction and major aqueousspecies which demonstrate this It can be seen that thedissolution of dolomite increases with increasing salinitywhile the dissolution-precipitation of other minerals andmajor aqueous species does not change except for minorcalcite precipitation This is in accordance with previousstudies [22 54] and can be explained by the ionic strengthof the solution increasing with salinity and reducing theactivity of aqueous species thereby promoting dolomitedissolution There was no obvious difference in the porositychanges between salinities of 009 (not shown) and 09wtdissolved NaClThis is probably because both those salinitiesare so low that there is no significant effect on mineralalteration and consequent porosity changes

34 Temporal and Spatial Evolution of Porosity and Perme-ability The injection of CO2 into the deep saline aquifersresults in a sequence of CO2-water-rock interactions induc-ing mineral dissolution and precipitation which can havea substantial impact on the porosity and permeability ofthe reservoir Figure 6 shows the evolution of porosities inthe Liujiagou Shiqianfeng and Shihezi formations Porositywithin each formation increases gradually with time and thevariation range of porosity is consistent with the migrationscope of CO2 this is consistent with the field observations[8] However the distribution of porosities is nonuniformin the range of CO2 plume This might be due to differentgeochemical reactions in different regions The three reser-voirs experienced increases in porosity of up to 010 012and 042 respectively depending on the primary mineralcompositions and reservoir conditions

Figure 7 shows the temporal and spatial evolution ofpermeability in the Liujiagou Shiqianfeng and Shiheziformations The three formations experienced increases inpermeability of up to 032 040 and 139The variationsin permeability agree with those of porosity (Figure 6)

Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)

Figure 7The evolution of permeability in the three formations ((a) Liujiagou formation (b) Shiqianfeng formation (c) Shihezi formation)

because that permeability is calculated from porosity using(2)

The supercritical CO2 saturation and nonuniform distri-bution of porosity change along the horizontal direction atthe depth of minus75m after 30 years of CO2 injection are shownin Figure 8 It can be seen that the distribution of reservoirporosity is closely related to the change of supercritical CO2saturation The reservoir system could be divided into threeregions according to supercritical CO2 saturation which are(1) zone I supercritical CO2 region where all the water hasbeen displaced or has evaporated and Sg is close to one(2) zone II CO2 and saline water region where the pHdecreases due to CO2 dissolution in the water phase andstabilizes at a pseudoequilibrium value of approximately 50and (3) zone III saline water region consisting of formationwaters undisturbed by injected CO2 The distribution ofporosity change corresponds to these three distinct regions ofsupercritical CO2 saturation (Figure 8) Porosity changes aredifferent between the three formations due to their differentphysical and chemical properties and the correspondingbalance of mineral dissolution and precipitation induced byCO2-water-rock interactions

The porosity change in the Liujiagou formation is themost limited it increases slightly within zone I at distancesof more than 3m from the injection well and there is amoderate uniform increase in porosity in zone II In zone IIIthe porosity does not change because the system maintainsits initial equilibrium state without CO2 disturbance Thechanges in porosity of the Shiqianfeng formation are slightlylarger than Liujiagou formation and the variation trend isdifferent in each region especially in zone I Among the threeformations the changes in porosity of the Shihezi formationare largest with the maximum changes located in zone II

The CO2-water-rock interactions after CO2 injectionlead to changes in porosity and permeability These changesare directly tied to mineral dissolution and precipitationcalculated by (1)-(2) [35] If the volume of minerals dissolvedis larger than the volume of those precipitated a porosityincrease results This will lead to an increase in permeabilitywhich consequently enhances the injectivity of CO2 intothe formation The differences in porosity changes betweenthe three formations indicate that different CO2-water-rockinteractions occur in the Liujiagou Shiqianfeng and Shiheziformations It can be concluded that porosity changes of zone

14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion

Sg_LiujiagouSg_ShiheziSg_Shiqianfeng

Por_LiujiagouPor_ShiheziPor_Shiqianfeng

012600126101262012630126401265

Poro

sity

1Radial distance (m)

10 100 1000 10000

Figure 8 The distribution of porosity and supercritical CO2saturation in the horizontal plane at the depth ofminus75m after 30 yearsof CO2 injection in the three formations

II are larger than those in zone I This is mainly becauseno condensed water is present in zone I and consequentlymineral reactions are limited while zone II is a two-phaseregion with sufficient saline water and CO2 for CO2-water-rock reactions to proceed rapidly

35 Comparison with Laboratory Experiments and PreviousOther Modeling Work With regard to Shenhua CCS demon-stration project the CO2-water-rock interactions and asso-ciated mineral dissolutionprecipitation after CO2 injectionhave been tested in laboratory experiments [43ndash45] andwe find good qualitative agreement with our results Tao[45] conducted batch reaction experiments with sandstoneusing a mixture of CO2 and brine fluids at temperaturesof 60∘C 80∘C and 100∘C and a pressure of 16MPa for 1to 25 days The sandstone samples were sourced from theLiujiagou group at the Shenhua CCS demonstration projectsite After the dissolution of CO2 SEM and EDS analysesshowed significant dissolution of primary minerals such asK-feldspar albite and chlorite and precipitation of secondaryminerals such as siderite and some clay minerals It shouldbe noted that albite here is corresponding to oligoclase in ourstudies These mineral alteration patterns are well consistentwith our simulations

Batch reactions were also conducted by Wang [43] andYang [44] using sandstone samples from the Shiqianfengformation and Shihezi formation Ordos Basin China Theexperiments were conducted for 24 days at temperaturesof 55∘C 70∘C 85∘C and 100∘C and the same pressures of18MPa SEM and EDS analyses showed albite and carbonatessuch as calcite and dolomite dissolved following the decreaseof pH after CO2 injection During the experiment thedissolution of carbonates buffered the fluid pH between 5 and73 The concentration of K+ Na+ and Ca2+ increased due tothe dissolution of initial dolomite and albiteTheir findings onthe amount of minerals alteration are in general agreementwith our simulations in which the dissolution of minerals

is larger than the precipitation and mineral dissolutionamount increased with increasing temperature in a certaintemperature range This can explain field observations wellthat the injectivity increased after CO2 injection

The experiments discussed showed there were only inter-mediate states of carbonate minerals and some unknownaluminosilicate minerals precipitated and the precipitationof clay minerals was rarely observedThis is in contrast to oursimulation results where precipitation of carbonates such asdawsonite and calcite and clay minerals such as smectite andkaolinite precipitation associated with oligoclase dissolutionwere predicted The differences are explained by factorssuch as kinetic and nucleation effects that likely prevent theformation of these minerals over the short time scales (only24 days) of the laboratory experiments [44 57]

In addition to batch experiments discussed above wehave also compared our results with previous reactivetransport modeling results [39 57 58] These simulationssuggested that mineral dissolution and precipitation inducedby CO2 injection have a major impact on the porosity andpermeability changes Liu et al [58] performed coupledreactive flow and transport modeling of CO2 injection inthe Mt Simon sandstone formation Midwest USA Theyfound dissolution of K-feldspar oligoclase and dolomiteoriginating in the matrix caused increase in porosity fromthe original 15 to 157 in the near-well zone during theinjection period which is in line with our simulation Inanother recent paper [57] the initial mineral compositionused in this work was similar with Shiqianfeng formation inour studies but the minerals contents and in situ conditions(eg temperature and pressure) are different Despite thesedifferences their results are well consistent with our studiesthat the increase in porosity is caused by the acidic brinethat triggered the dissolution of minerals such as calcite andalbite (corresponding to oligoclase in our studies) Also theformation of dawsonite was observed in both models

4 Conclusions

This study investigated CO2-water-rock geochemical reac-tions during CO2 injection at the Shenhua CCS demon-stration site using two-dimensional (2D) reactive trans-port model The potential role of mineral dissolution andprecipitation (and resulting porosity change) in explain-ing the nearly tenfold increase in injectivity observed atthat site was explored using conventional and alternativeporosity-permeability models The effect on mineral dissolu-tionprecipitation of keymineral composition (eg dolomitecalcite and oligoclase) and formation physical properties(eg temperature pressure and brine salinity) was alsoexamined The conclusions are as follows

The CO2-water-rock interactions induced by CO2 injec-tion into the deep saline aquifers affect the porosity evolutionof the reservoir due to mineral dissolution and precipitationThe porosities of the three formations increase graduallyover time during CO2 injection and the spatial distributionof porosity change is consistent with the migration scopeof CO2 The porosities of the Liujiagou Shiqianfeng andShihezi reservoirs experienced maximum increases of 010

Geofluids 15

012 and 042 respectively The differences in porositychanges between these three formations are a consequence ofthe different CO2-water-rock interactions occurring due totheir different primary mineral compositions and reservoirconditions

The reservoir permeability will increase as a consequenceof the porosity increase Using a typical Kozeny-Carmanporosity-permeability relationship the nearly tenfold injec-tivity increase observed cannot be attributed to CO2-water-rock interaction-induced mineral dissolution How-ever using porosity-permeability relationships that includetortuosity grain size and percolation porosity it is possibleto explain the injectivity increase as a consequence ofmineraldissolution These models might be justified in terms ofselective dissolution along flow paths and by dissolutionor migration of plugging fines Empirical studies usingcore samples would be necessary to evaluate the suitabilityof applying these alternative models to the Shenhua CCSsite Further research could also explore the near-wellboreporosity-permeability changes at the early stage of CO2injection and also as to whether more extreme variationsin reservoir properties could explain permeability changesunder a Kozeny-Carman porosity-permeability relationship

Variation of key mineral composition and physical reser-voir parameters illustrates that dolomite is the key mineralthat affects porosity increase during CO2 injection andthe dissolution of dolomite can inhibit the dissolution ofcalcite The dissolution of oligoclase can also lead to porosityincrease although oligoclase can also inhibit the dissolutionof dolomite which is not conducive to porosity increaseFormation physical properties such as temperature pressureand brine salinity are all important factors that affect mineraldissolution and precipitation as well as relevant porosity andpermeability changes

The simulation results are comparedwith available exper-imental data and found to show reasonably good agreementThese results indicate the importance of localized mineraldissolution during CO2-water-rock interactions which canlead to a large increase in the volume of void space therebyincreasing the porosity and permeability of the reservoirThisstudy helps deepen our understanding of how geochemicalchanges may affect CO2 injectivity Results from this studycould have important practical implications for a successfulCO2 injection and enhanced oilgasgeothermal productionin low-permeability formations providing a new basis forscreening of themost effective storage sites and reservoirs andassessing CO2 injectivity by considering specific mineralogyand in situ conditions

Conflicts of Interest

The authors declare that there are no conflicts of interestregarding the publication of this paper

Acknowledgments

This work was supported by the National Natural ScienceFoundation of China (NSFC Grant nos 41602272 and

41572233) a bilateral project China Australia GeologicalStorage of CO2 Project Phase 2 (CAGS2) and the projectfunded byChina Postdoctoral Science Foundation (Grant no2016M592405)

References

[1] S Bachu ldquoSequestration of CO2 in geologicalmedia in responseto climate change Road map for site selection using thetransform of the geological space into the CO2 phase spacerdquoEnergy Conversion and Management vol 43 no 1 pp 87ndash1022002

[2] IPCC ldquoIPCC Special Report on carbon dioxide capture andstoragerdquo in Prepared by Working Group III of the Intergovern-mental Panel on Climate Change p 442 Cambridge UniversityPress Cambridge UK 2005

[3] P J Cook ldquoDemonstration andDeployment of CarbonDioxideCapture and Storage inAustraliardquo inProceedings of the 9th Inter-national Conference on Greenhouse Gas Control TechnologiesGHGT-9 pp 3859ndash3866 November 2008

[4] C Hermanrud T Andresen O Eiken et al ldquoStorage of CO2 insaline aquifers-Lessons learned from 10 years of injection intothe Utsira Formation in the Sleipner areardquo Energy Procedia vol1 pp 1997ndash2004

[5] S Whittaker B Rostron C Hawkes et al ldquoA decade of CO2injection into depleting oil fields monitoring and researchactivities of the IEA GHG Weyburn-Midale CO2 Monitoringand Storage Projectrdquo Energy Procedia vol 4 pp 6069ndash60762011

[6] J Lu Y K Kharaka J J Thordsen et al ldquoCO2mdashrockmdashbrineinteractions in Lower Tuscaloosa Formation at Cranfield CO2sequestration site Mississippi USArdquo Chemical Geology vol291 pp 269ndash277 2012

[7] T Kempka and M Kuhn ldquoNumerical simulations of CO2arrival times and reservoir pressure coincide with observationsfrom the Ketzin pilot site Germanyrdquo Environmental EarthSciences vol 70 pp 3675ndash3685 2013

[8] XWuCarbonDioxide Capture andGeological StorageThe FirstMassive Exploration in China Beijing Science Press BeijingChina 2013

[9] Q Li G Liu X Liu and X Li ldquoApplication of a health safetyand environmental screening and ranking framework to theShenhua CCS projectrdquo International Journal of Greenhouse GasControl vol 17 pp 504ndash514 2013

[10] China Shenhua Coal to Liquid and Chemical EngineeringCompany The operation report of the Shenhua 01 Mt CCSDemonstration Project 2014

[11] T A Buscheck Y Sun M Chen et al ldquoActive CO2 reser-voir management for carbon storage Analysis of operationalstrategies to relieve pressure buildup and improve injectivityrdquoInternational Journal of Greenhouse Gas Control vol 6 pp 230ndash245 2012

[12] L Andre Y Peysson and M Azaroual ldquoWell injectivity duringCO2 storage operations in deep saline aquifers - Part 2Numerical simulations of drying salt deposit mechanisms androle of capillary forcesrdquo International Journal of Greenhouse GasControl vol 22 pp 301ndash312 2014

[13] Q Li Y-N Wei G Liu and Q Lin ldquoCombination of CO2geological storage with deep saline water recovery in westernChina Insights from numerical analysesrdquo Applied Energy vol116 pp 101ndash110 2014

16 Geofluids

[14] L Andre P AudiganeMAzaroual andAMenjoz ldquoNumericalmodeling of fluid-rock chemical interactions at the supercriticalCO2-liquid interface during CO2 injection into a carbonatereservoir the Dogger aquifer (Paris Basin France)rdquo EnergyConversion and Management vol 48 pp 1782ndash1797 2007

[15] L Luquot and P Gouze ldquoExperimental determination ofporosity and permeability changes induced by injection of CO2into carbonate rocksrdquo Chemical Geology vol 265 pp 148ndash1592009

[16] Y Hao M Smith Y Sholokhova and S Carroll ldquoCO2-induceddissolution of low permeability carbonates Part II Numericalmodeling of experimentsrdquoAdvances inWater Resources vol 62pp 388ndash408 2013

[17] G P D De Silva P G Ranjith and M S A Perera ldquoGeo-chemical aspects of CO2 sequestration in deep saline aquifersA reviewrdquo Fuel vol 155 pp 128ndash143 2015

[18] C F J Colon E H Oelkers and J Schott ldquoExperimentalinvestigation of the effect of dissolution on sandstone per-meability porosity and reactive surface areardquo Geochimica etCosmochimica Acta vol 68 pp 805ndash817 2004

[19] O Izgec B Demiral H Bertin and S Akin ldquoCO2 injection intosaline carbonate aquifer formations I Laboratory investigationrdquoTransport in Porous Media vol 72 pp 1ndash24 2008

[20] M M Smith Y Sholokhova Y Hao and S A CarrollldquoCO2-induced dissolution of low permeability carbonatesPart I Characterization and experimentsrdquo Advances in WaterResources vol 62 pp 370ndash387 2013

[21] A J Luhmann X-Z Kong B M Tutolo et al ldquoExperimentaldissolution of dolomite by CO2-charged brine at 100∘C and150 bar Evolution of porosity permeability and reactive surfaceareardquo Chemical Geology vol 380 pp 145ndash160 2014

[22] B M Tutolo A J Luhmann X Kong M O Saar andW E Seyfried ldquoExperimental Observation of PermeabilityChanges In Dolomite at CO2 Sequestration Conditionsrdquo inEnvironmental Science amp Technology vol 48 pp 2445ndash24522014

[23] O Izgec B Demiral H Bertin and S Akin ldquoCO2 injectioninto saline carbonate aquifer formations II Comparison ofnumerical simulations to experimentsrdquo Transport in PorousMedia vol 73 pp 57ndash74 2008

[24] M A Sbai andMAzaroual ldquoNumericalmodeling of formationdamage by two-phase particulate transport processes duringCO2 injection in deep heterogeneous porous mediardquo Advancesin Water Resources vol 34 pp 62ndash82 2011

[25] S Sadhukhan P Gouze and T Dutta ldquoPorosity and perme-ability changes in sedimentary rocks induced by injection ofreactive fluid A simulation modelrdquo Journal of Hydrology vol450-451 pp 134ndash139 2012

[26] J P Nogues J P Fitts M A Celia and C A Peters ldquoPermeabil-ity evolution due to dissolution and precipitation of carbonatesusing reactive transport modeling in pore networksrdquo WaterResources Research vol 49 pp 6006ndash6021 2013

[27] S Molins D Trebotich L Yang et al ldquoPore-scale controlson calcite dissolution rates from flow-through laboratory andnumerical experimentsrdquo Environmental Science amp Technologyvol 48 pp 7453ndash7460 2014

[28] B M Tutolo A J Luhmann X-Z Kong M O Saar andW E Seyfried ldquoCO2 sequestration in feldspar-rich sandstoneCoupled evolution of fluid chemistry mineral reaction ratesand hydrogeochemical propertiesrdquo Geochimica et Cosmochim-ica Acta vol 160 pp 132ndash154 2015

[29] N Wei M Gill D Crandall et al ldquoCO2 flooding propertiesof Liujiagou sandstone Influence of sub-core scale structureheterogeneityrdquo Greenhouse Gases Science and Technology vol4 pp 400ndash418 2014

[30] W B Fei Q Li X C Wei et al ldquoInteraction analysis forCO2 geological storage and underground coal mining in OrdosBasin Chinardquo Engineering Geology vol 196 pp 194ndash209 2015

[31] Q Zhu D Zuo S Zhang et al ldquoSimulation of geomechanicalresponses of reservoirs induced by CO2 multilayer injectionin the Shenhua CCS project Chinardquo International Journal ofGreenhouse Gas Control vol 42 pp 405ndash414 2015

[32] Q Li H Shi D Yang andXWei ldquoModeling the key factors thatcould influence the diffusion of CO2 from awellbore blowout inthe Ordos Basin Chinardquo Environmental Science and PollutionResearch vol 24 pp 3727ndash3738 2017

[33] D Liu Y Li S Song and R Agarwal ldquoSimulation and analysisof lithology heterogeneity on CO2 geological sequestrationin deep saline aquifer a case study of the Ordos BasinrdquoEnvironmental Earth Sciences vol 75 pp 1ndash13 2016

[34] T Xu E Sonnenthal N Spycher and K PruessldquoTOUGHREACTmdashA simulation program for non-isothermalmultiphase reactive geochemical transport in variably saturatedgeologic media Applications to geothermal injectivity andCO2 geological sequestrationrdquo Computers amp Geosciences vol32 pp 145ndash165 2006

[35] T Xu N Spycher E Sonnenthal L Zheng and K PruessldquoTOUGHREACT userrsquos guide a simulation program for non-isothermal multiphase reactive transport in variably saturatedgeologicmedia Version 20rdquo Earth SciencesDivision LawrenceBerkeley National Laboratory University of California Berke-ley CA USA 2012

[36] K Pruess C Oldenburg and G Moridis ldquoTOUGH2 userrsquosguide Version 20rdquo Lawrence Berkeley Laboratory Report LBL-43134 Berkeley CA USA 1999

[37] N Spycher andK Pruess ldquoCO2-H2Omixtures in the geologicalsequestration of CO2 II Partitioning in chloride brines at12ndash100∘C and up to 600 barrdquoGeochimica et Cosmochimica Actavol 69 pp 3309ndash3320 2005

[38] T J Wolery ldquoSoftware package for geochemical modelingof aqueous system Package overview and installation guide(version 80)rdquo Lawrence LivermoreNational Laboratory ReportUCRL-MA-110662 PT I Livermore California USA 1992

[39] L Andre M Azaroual and A Menjoz ldquoNumerical simula-tions of the thermal impact of supercritical CO2 injection onchemical reactivity in a carbonate saline reservoirrdquo Transport inPorous Media vol 82 pp 247ndash274 2010

[40] Y Wang The Research Report of the Shenhua 01 Mt CCSDemonstration Project The Appraisal Meeting of the Shenhua01 Mt CCS Demonstration Project Ordos China 2014

[41] M T van Genuchten ldquoA closed-form equation for predictingthe hydraulic conductivity of unsaturated soilsrdquo Soil ScienceSociety of America Journal vol 44 no 5 pp 892ndash898 1980

[42] A T Corey The Interrelation between Gas and Oil RelativePermeabilities 1954

[43] HWang ldquoStudy on the interaction of CO2 fluid with sandstonein Shiqianfengrdquo Jilin University 2012

[44] X Yang Experimental study of CO2 fluid on the geologicaltransformation of reservoir sandstone In Jilin University 2012

[45] Y Tao Experimental study on the interaction of CO2CO2-H2Sfluid with sandstone in Liujiagou Jilin University 2013

Geofluids 17

[46] T Xu J A Apps and K Pruess ldquoNumerical simulation ofCO2 disposal by mineral trapping in deep aquifersrdquo AppliedGeochemistry vol 19 pp 917ndash936 2004

[47] T Xu J A Apps and K Pruess ldquoMineral sequestration ofcarbon dioxide in a sandstone-shale systemrdquoChemical Geologyvol 217 pp 295ndash318 2005

[48] W Zhang Y Li T Xu et al ldquoLong-term variations of CO2trapped in different mechanisms in deep saline formations Acase study of the Songliao Basin Chinardquo International Journalof Greenhouse Gas Control vol 3 no 2 pp 161ndash180 2009

[49] G Yang Y Li X Ma and J Dong ldquoEffect of chlorite onCO2-water-rock interactionrdquo Earth SciencemdashJournal of ChinaUniversity of Geosciences vol 39 pp 462ndash472 2014

[50] Y Wan Migration and transformation of CO2 in CO2geologicalsequestration process of Shiqianfeng saline aquifers in OrdosBasin Jilin University 2012

[51] T Xu Y K Kharaka C Doughty B M Freifeld and T MDaley ldquoReactive transport modeling to study changes in waterchemistry induced by CO2 injection at the Frio-I Brine PilotrdquoChemical Geology vol 271 pp 153ndash164 2010

[52] C T Gomez J Dvorkin and T Vanorio ldquoLaboratory mea-surements of porosity permeability resistivity and velocityon Fontainebleau sandstonesrdquo Geophysics vol 75 pp 191ndash2042010

[53] A S Ziarani and R Aguilera ldquoPore-throat radius and tortuosityestimation from formation resistivity data for tight-gas sand-stone reservoirsrdquo Journal of Applied Geophysics vol 83 pp 65ndash73 2012

[54] Z Yan and Z Zhang ldquoThe effect of chloride on the solubility ofcalcite and dolomiterdquoHydrogeology amp Engineering Geology vol36 pp 113ndash118 2009

[55] L Xiao and S Huang ldquoModel of thermodynamics for disso-lution of carbonate and its geological significancesrdquo Journal ofMineralogy amp Petrology vol 23 pp 113ndash116 2003

[56] Z Yan H Liu and Z Zhang ldquoInfluences of temperature andPCO2

on the solubility of calcite and dolomiterdquo CarsologicaSinica vol 28 pp 7ndash10 2009

[57] S M Amin D J Weiss and M J Blunt ldquoReactive transportmodelling of geologic CO2 sequestration in saline aquifersTheinfluence of pure CO2 and of mixtures of CO2 with CH4 onthe sealing capacity of cap rock at 37 degrees C and 100 barrdquoChemical Geology vol 367 pp 39ndash50 2014

[58] F Liu P Lu C Zhu and Y Xiao ldquoCoupled reactive flow andtransport modeling of CO2 sequestration in the Mt Simonsandstone formation Midwest USArdquo International Journal ofGreenhouse Gas Control vol 5 pp 294ndash307 2011

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

EcologyInternational Journal of


EarthquakesJournal of


Mining


Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 201

International Journal of

OceanographyInternational Journal of


Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofPetroleum Engineering


GeochemistryHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Atmospheric SciencesInternational Journal of


OceanographyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in


MineralogyInternational Journal of


MeteorologyAdvances in

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Paleontology JournalHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014


Geological ResearchJournal of


Geology Advances in

2 Geofluids

injectivity increases after injection started which is differentfrom earlier predictions [8]

For large-scale injection of CO2 into saline formationsCO2 injectivity is a key technical and economic issue ofconcern Previous studies and applications show that CO2injectivity can be affected by the following mechanisms (1)pressure build-up due to massive and continuous CO2 injec-tion (2) dry-out of the near-well zone due to evaporation ofH2O into unsaturated CO2 (3) CO2-water-rock interactionsinduced by the injection of CO2 (Bacci et al 2011) [11ndash13]Among these processes CO2-water-rock interactions couldalter the rock matrix and potentially lead to porosity andpermeability changes in the near-well zone [14ndash17] which isof particular importance for CO2 injectivity

Laboratory experiments related to CO2 injection intosandstone and carbonate rocks have been reported in theprevious studies [15 18ndash22] These experiments indicate thatCO2-water-rock interactions can have a substantial effect onporosity and permeability depending on fluid compositionrockmineralogy and subsurface thermodynamic conditionsThey found that carbonate dissolution processes seem to bethemain cause of permeability increases and promote a rapidspreading of the reaction front in short time scales

Reactive transport modeling has been previously usedto investigate geochemical reactions and their effects onpermeability and porosity evolution [14 15 23ndash26] Andreet al [14] simulated CO2 storage in the carbonate-richDogger aquifer in the Paris Basin (France) using the reactivetransport simulator TOUGHREACT They found that theporosity in the near-well zone increased significantly dueto mineral dissolution This was in accordance with thereactive flow-through experimental study by Luquot andGouze [15] for the same basin Some studies [25 26] alsoreported that geochemical reactions dissolved the host rockincreasing porosity and permeability thereby affecting fluidflow through reactive transportmodeling On the other handIzgec et al [23] found that CO2 injection into carbonateaquifers simulated using CMGrsquos STARS could result inpermeability reduction as well as improvement dependingon the balance between mineral dissolution and precipita-tion Furthermore Sbai and Azaroual [24] found that CO2injection could in some circumstances cause particulates toclog reservoir pores leading to a permeability reduction andinjectivity decline near the injection well

Laboratory experiments imaging characterization andnumerical modeling have previously been combined todescribe mineral alteration and associated reactive transportprocesses and mechanisms in porous media induced byCO2 injection (Bacci et al 2011) [16 27 28] Those studiesfocused on pore- or continuum-scale transport and reac-tion processes and indicated that CO2 injectivity increasesfrom dissolution of both carbonate and silicate minerals(especially feldspars) They also confirmed the rapid reactionkinetics of carbonate minerals compared to silicate mineralsAmong these research approaches numerical modeling is anexcellent technique in which CO2 injection and geochemicalperformance can bemodeled at different temporal and spatialscales

In general previous studies reveal that CO2-water-rockinteractions induce mineral dissolution and precipitationwhich can consequently change the porosity andpermeabilityof the subsurface matrix and thus affect the CO2 injectivityand overall storage capacity The trend and magnitude ofchange in porosity and permeability are highly reservoirspecific and depend on reservoir properties which are relatedto particle sizes brine composition and as well the thermo-dynamic conditions

Analyses of geohydrological mechanical thermal andgeochemical processes involved in Shenhua CCS project havebeen reported [29ndash33]However few of these have focused onthe considerable CO2 injectivity increase during CO2 injec-tion period Liu et al [33] examined this unique phenomenonthrough numerical simulation and concluded that it could beexplained through heterogeneities in reservoir permeabilityHowever their approach did not consider the possible role ofCO2-water-rock interactions on CO2 injectivity

In this study we applied a 2D radial injectionmodel usingthe reactive transport code TOUGHREACT to investigatethe effect of CO2-water-rock geochemical reactions on CO2injectivity through the evolution of the formation porosityand permeability at the Shenhua CCS site We focus onLiujiagou Shiqianfeng and Shihezi formations which are thethree main formations that sequestrate more than 90 oftotal CO2 injected The goal is to determine the key mech-anisms controlling the CO2-water-rock interactions duringCO2 injection particularly focusing on investigation of thereasons for CO2 injectivity improvement in the ShenhuaCCS project Moreover we examined the impact of variousparameters on mineral dissolutionprecipitation as well asrelevant porosity and permeability changes and comparedthe simulation results with available experimental dataUnderstanding of these mechanisms could have importantpractical implications for a successful CO2 injection andstorage operation in low-permeability formations providinga new basis for screening of the storage sites and reservoirsand assessing CO2 injectivity from a geochemical point ofview

2 Modeling Approach

21 Numerical Tool The simulations presented in thisstudy were carried out using the reactive transport codeTOUGHREACT [34 35] which introduces reactive geo-chemistry into the multiphase fluid and heat flow codeTOUGH2 V2 [36] A fluid property module ECO2N [37]was used to describe isothermal or nonisothermalmultiphaseflow in H2O-NaCl-CO2 system under conditions typicallyencountered in saline aquifers of interest for CO2 seques-tration (31∘C le 119879 le 110∘C 738MPa lt 119875 le 60MPa)TOUGHREACT is a thermal-physical-chemical code appli-cable to one- two- or three-dimensional geologic systemswith physical and chemical heterogeneity The numericalmethod for fluid flow and chemical transport simulationis based on the integral finite difference (IFD) methodfor space discretization The system of chemical reactionequations is solved on a grid-block basis by Newton-Raphsoniteration Thermodynamic data used in the simulations were

Geofluids 3

(a)

QCO2 = 317 kgs

100 m

02 m 10000 m

Injection well

Impermeable caprock

Impermeable bedrock

Sandstone formation

01 Mtyearasymp

(b)




120601 = 1 minus119886119887

sum119887=1

f r119887 minus f r119906 (1)



119896 = 119896119894 (1 minus 120601119894)2(1 minus 120601)2 (

120601120601119894)3

(2)







4 Geofluids















119869 = 119902Δ119875 prop 2120587119896ℎ

120583 ln (119903119903119903119908) (3)


119869119869119894 =

119896sum119899119894 119896119894 ln (119903119894119903119894minus1) (4)


Geofluids 5



















119896 = 119896119894 1198892

119889119894212059111989421205912

(1 minus 120601119894 + 120601119901)2(1 minus 120601 + 120601119901)2

(120601 minus 120601119901)3(120601119894 minus 120601119901)3

(5)



6 Geofluids









+ 2HCO3minus

(6)



(8)

Geofluids 7




minus00008

minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

01000

01001

Poro

sityPorosity

1 10 100 100001 10000

Radial distance (m)

(a)

pH

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

Ca2+

Mg2+

Fe2+

SiO2 (aq)

CO2 (aq)


0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(b)


IlliteKaolinite

AnhydriteCalcite

Oligoclase


minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

als v

olum

e fra

ctio

n

Porosity01290

01291

Poro

sity

1 10 10000100010001

Radial distance (m)

(c)

pH

Ca2+Fe2+

SiO2 (aq)CO2 (aq)


1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10Th

e con

cent

ratio

n of

aque

ous s

peci

es

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(d)



Ca-smectite

Porosity0126201260

01264

Poro

sity

1 10 10000100010001

Radial distance (m)

minus00010

minus00008

minus00006

minus00004

minus00002

00000

00002

00004

00006

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

(e)

pH

Ca2+

Mg2+

SiO2 (aq)CO2 (aq)

Zone IIZone I

Zone III

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(f)


8 Geofluids



minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


(a)


Calcite

Oligoclase


minus80

minus60

minus40

minus20

0

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus7E minus 05

minus4E minus 05

minus1E minus 05

(b)

Dolomite


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

00 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)



(c)



(9)


(10)


Geofluids 9





()0


Salinity (wt)009

Case 12 9Case 13 15











10 Geofluids


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

e

Kaolinite

Calcite

Oligoclase


Quartz

Dolomite


frac

tion

(b)


0

2

4

6

8

10

pH

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

Ca2+

SiO2(aq)

CO2 (aq) Mg2+


HCO3minus

(c)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(d)

Zone II

Zone I Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(e)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(f)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(g)

Zone II

Zone I

Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(h)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(i)





Geofluids 11

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro


T_50∘CT_67∘CT_80∘C

(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite

T_50∘CT_67∘CT_80∘C

(b)

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


0246810

pH

T_50∘CT_67∘CT_80∘C

HCO3minus

(c)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(d)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(e)


pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

HCO3minus


(f)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(g)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(h)


100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

HCO3minus


(i)






12 Geofluids

Porosity010011010009010007010005010003010001

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(a)

Porosity012915012912501291012907501290501290250129

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(b)


0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)





Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

Geofluids 3

(a)

QCO2 = 317 kgs

100 m

02 m 10000 m

Injection well

Impermeable caprock

Impermeable bedrock

Sandstone formation

01 Mtyearasymp

(b)




120601 = 1 minus119886119887

sum119887=1

f r119887 minus f r119906 (1)



119896 = 119896119894 (1 minus 120601119894)2(1 minus 120601)2 (

120601120601119894)3

(2)







4 Geofluids















119869 = 119902Δ119875 prop 2120587119896ℎ

120583 ln (119903119903119903119908) (3)


119869119869119894 =

119896sum119899119894 119896119894 ln (119903119894119903119894minus1) (4)


Geofluids 5



















119896 = 119896119894 1198892

119889119894212059111989421205912

(1 minus 120601119894 + 120601119901)2(1 minus 120601 + 120601119901)2

(120601 minus 120601119901)3(120601119894 minus 120601119901)3

(5)



6 Geofluids









+ 2HCO3minus

(6)



(8)

Geofluids 7




minus00008

minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

01000

01001

Poro

sityPorosity

1 10 100 100001 10000

Radial distance (m)

(a)

pH

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

Ca2+

Mg2+

Fe2+

SiO2 (aq)

CO2 (aq)


0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(b)


IlliteKaolinite

AnhydriteCalcite

Oligoclase


minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

als v

olum

e fra

ctio

n

Porosity01290

01291

Poro

sity

1 10 10000100010001

Radial distance (m)

(c)

pH

Ca2+Fe2+

SiO2 (aq)CO2 (aq)


1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10Th

e con

cent

ratio

n of

aque

ous s

peci

es

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(d)



Ca-smectite

Porosity0126201260

01264

Poro

sity

1 10 10000100010001

Radial distance (m)

minus00010

minus00008

minus00006

minus00004

minus00002

00000

00002

00004

00006

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

(e)

pH

Ca2+

Mg2+

SiO2 (aq)CO2 (aq)

Zone IIZone I

Zone III

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(f)


8 Geofluids



minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


(a)


Calcite

Oligoclase


minus80

minus60

minus40

minus20

0

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus7E minus 05

minus4E minus 05

minus1E minus 05

(b)

Dolomite


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

00 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)



(c)



(9)


(10)


Geofluids 9





()0


Salinity (wt)009

Case 12 9Case 13 15











10 Geofluids


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

e

Kaolinite

Calcite

Oligoclase


Quartz

Dolomite


frac

tion

(b)


0

2

4

6

8

10

pH

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

Ca2+

SiO2(aq)

CO2 (aq) Mg2+


HCO3minus

(c)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(d)

Zone II

Zone I Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(e)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(f)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(g)

Zone II

Zone I

Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(h)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(i)





Geofluids 11

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro


T_50∘CT_67∘CT_80∘C

(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite

T_50∘CT_67∘CT_80∘C

(b)

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


0246810

pH

T_50∘CT_67∘CT_80∘C

HCO3minus

(c)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(d)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(e)


pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

HCO3minus


(f)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(g)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(h)


100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

HCO3minus


(i)






12 Geofluids

Porosity010011010009010007010005010003010001

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(a)

Porosity012915012912501291012907501290501290250129

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(b)


0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)





Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

4 Geofluids















119869 = 119902Δ119875 prop 2120587119896ℎ

120583 ln (119903119903119903119908) (3)


119869119869119894 =

119896sum119899119894 119896119894 ln (119903119894119903119894minus1) (4)


Geofluids 5



















119896 = 119896119894 1198892

119889119894212059111989421205912

(1 minus 120601119894 + 120601119901)2(1 minus 120601 + 120601119901)2

(120601 minus 120601119901)3(120601119894 minus 120601119901)3

(5)



6 Geofluids









+ 2HCO3minus

(6)



(8)

Geofluids 7




minus00008

minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

01000

01001

Poro

sityPorosity

1 10 100 100001 10000

Radial distance (m)

(a)

pH

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

Ca2+

Mg2+

Fe2+

SiO2 (aq)

CO2 (aq)


0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(b)


IlliteKaolinite

AnhydriteCalcite

Oligoclase


minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

als v

olum

e fra

ctio

n

Porosity01290

01291

Poro

sity

1 10 10000100010001

Radial distance (m)

(c)

pH

Ca2+Fe2+

SiO2 (aq)CO2 (aq)


1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10Th

e con

cent

ratio

n of

aque

ous s

peci

es

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(d)



Ca-smectite

Porosity0126201260

01264

Poro

sity

1 10 10000100010001

Radial distance (m)

minus00010

minus00008

minus00006

minus00004

minus00002

00000

00002

00004

00006

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

(e)

pH

Ca2+

Mg2+

SiO2 (aq)CO2 (aq)

Zone IIZone I

Zone III

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(f)


8 Geofluids



minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


(a)


Calcite

Oligoclase


minus80

minus60

minus40

minus20

0

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus7E minus 05

minus4E minus 05

minus1E minus 05

(b)

Dolomite


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

00 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)



(c)



(9)


(10)


Geofluids 9





()0


Salinity (wt)009

Case 12 9Case 13 15











10 Geofluids


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

e

Kaolinite

Calcite

Oligoclase


Quartz

Dolomite


frac

tion

(b)


0

2

4

6

8

10

pH

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

Ca2+

SiO2(aq)

CO2 (aq) Mg2+


HCO3minus

(c)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(d)

Zone II

Zone I Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(e)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(f)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(g)

Zone II

Zone I

Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(h)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(i)





Geofluids 11

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro


T_50∘CT_67∘CT_80∘C

(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite

T_50∘CT_67∘CT_80∘C

(b)

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


0246810

pH

T_50∘CT_67∘CT_80∘C

HCO3minus

(c)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(d)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(e)


pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

HCO3minus


(f)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(g)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(h)


100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

HCO3minus


(i)






12 Geofluids

Porosity010011010009010007010005010003010001

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(a)

Porosity012915012912501291012907501290501290250129

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(b)


0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)





Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

Geofluids 5



















119896 = 119896119894 1198892

119889119894212059111989421205912

(1 minus 120601119894 + 120601119901)2(1 minus 120601 + 120601119901)2

(120601 minus 120601119901)3(120601119894 minus 120601119901)3

(5)



6 Geofluids









+ 2HCO3minus

(6)



(8)

Geofluids 7




minus00008

minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

01000

01001

Poro

sityPorosity

1 10 100 100001 10000

Radial distance (m)

(a)

pH

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

Ca2+

Mg2+

Fe2+

SiO2 (aq)

CO2 (aq)


0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(b)


IlliteKaolinite

AnhydriteCalcite

Oligoclase


minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

als v

olum

e fra

ctio

n

Porosity01290

01291

Poro

sity

1 10 10000100010001

Radial distance (m)

(c)

pH

Ca2+Fe2+

SiO2 (aq)CO2 (aq)


1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10Th

e con

cent

ratio

n of

aque

ous s

peci

es

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(d)



Ca-smectite

Porosity0126201260

01264

Poro

sity

1 10 10000100010001

Radial distance (m)

minus00010

minus00008

minus00006

minus00004

minus00002

00000

00002

00004

00006

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

(e)

pH

Ca2+

Mg2+

SiO2 (aq)CO2 (aq)

Zone IIZone I

Zone III

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(f)


8 Geofluids



minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


(a)


Calcite

Oligoclase


minus80

minus60

minus40

minus20

0

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus7E minus 05

minus4E minus 05

minus1E minus 05

(b)

Dolomite


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

00 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)



(c)



(9)


(10)


Geofluids 9





()0


Salinity (wt)009

Case 12 9Case 13 15











10 Geofluids


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

e

Kaolinite

Calcite

Oligoclase


Quartz

Dolomite


frac

tion

(b)


0

2

4

6

8

10

pH

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

Ca2+

SiO2(aq)

CO2 (aq) Mg2+


HCO3minus

(c)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(d)

Zone II

Zone I Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(e)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(f)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(g)

Zone II

Zone I

Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(h)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(i)





Geofluids 11

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro


T_50∘CT_67∘CT_80∘C

(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite

T_50∘CT_67∘CT_80∘C

(b)

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


0246810

pH

T_50∘CT_67∘CT_80∘C

HCO3minus

(c)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(d)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(e)


pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

HCO3minus


(f)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(g)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(h)


100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

HCO3minus


(i)






12 Geofluids

Porosity010011010009010007010005010003010001

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(a)

Porosity012915012912501291012907501290501290250129

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(b)


0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)





Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

6 Geofluids









+ 2HCO3minus

(6)



(8)

Geofluids 7




minus00008

minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

01000

01001

Poro

sityPorosity

1 10 100 100001 10000

Radial distance (m)

(a)

pH

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

Ca2+

Mg2+

Fe2+

SiO2 (aq)

CO2 (aq)


0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(b)


IlliteKaolinite

AnhydriteCalcite

Oligoclase


minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

als v

olum

e fra

ctio

n

Porosity01290

01291

Poro

sity

1 10 10000100010001

Radial distance (m)

(c)

pH

Ca2+Fe2+

SiO2 (aq)CO2 (aq)


1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10Th

e con

cent

ratio

n of

aque

ous s

peci

es

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(d)



Ca-smectite

Porosity0126201260

01264

Poro

sity

1 10 10000100010001

Radial distance (m)

minus00010

minus00008

minus00006

minus00004

minus00002

00000

00002

00004

00006

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

(e)

pH

Ca2+

Mg2+

SiO2 (aq)CO2 (aq)

Zone IIZone I

Zone III

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(f)


8 Geofluids



minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


(a)


Calcite

Oligoclase


minus80

minus60

minus40

minus20

0

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus7E minus 05

minus4E minus 05

minus1E minus 05

(b)

Dolomite


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

00 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)



(c)



(9)


(10)


Geofluids 9





()0


Salinity (wt)009

Case 12 9Case 13 15











10 Geofluids


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

e

Kaolinite

Calcite

Oligoclase


Quartz

Dolomite


frac

tion

(b)


0

2

4

6

8

10

pH

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

Ca2+

SiO2(aq)

CO2 (aq) Mg2+


HCO3minus

(c)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(d)

Zone II

Zone I Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(e)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(f)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(g)

Zone II

Zone I

Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(h)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(i)





Geofluids 11

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro


T_50∘CT_67∘CT_80∘C

(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite

T_50∘CT_67∘CT_80∘C

(b)

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


0246810

pH

T_50∘CT_67∘CT_80∘C

HCO3minus

(c)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(d)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(e)


pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

HCO3minus


(f)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(g)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(h)


100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

HCO3minus


(i)






12 Geofluids

Porosity010011010009010007010005010003010001

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(a)

Porosity012915012912501291012907501290501290250129

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(b)


0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)





Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

Geofluids 7




minus00008

minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

01000

01001

Poro

sityPorosity

1 10 100 100001 10000

Radial distance (m)

(a)

pH

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

Ca2+

Mg2+

Fe2+

SiO2 (aq)

CO2 (aq)


0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(b)


IlliteKaolinite

AnhydriteCalcite

Oligoclase


minus00006

minus00004

minus00002

00000

00002

00004

Chan

ges i

n m

iner

als v

olum

e fra

ctio

n

Porosity01290

01291

Poro

sity

1 10 10000100010001

Radial distance (m)

(c)

pH

Ca2+Fe2+

SiO2 (aq)CO2 (aq)


1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10Th

e con

cent

ratio

n of

aque

ous s

peci

es

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(d)



Ca-smectite

Porosity0126201260

01264

Poro

sity

1 10 10000100010001

Radial distance (m)

minus00010

minus00008

minus00006

minus00004

minus00002

00000

00002

00004

00006

Chan

ges i

n m

iner

al v

olum

e fra

ctio

n

(e)

pH

Ca2+

Mg2+

SiO2 (aq)CO2 (aq)

Zone IIZone I

Zone III

1 10 100 1000 1000001

Radial distance (m)

1E minus 6

1E minus 5

1E minus 4

1E minus 3

001

01

1

10

The c

once

ntra

tion

of aq

ueou

s spe

cies

0

2

4

6

8

10

pH

(mol

kg)

HCO3minus

(f)


8 Geofluids



minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


(a)


Calcite

Oligoclase


minus80

minus60

minus40

minus20

0

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus7E minus 05

minus4E minus 05

minus1E minus 05

(b)

Dolomite


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

00 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)



(c)



(9)


(10)


Geofluids 9





()0


Salinity (wt)009

Case 12 9Case 13 15











10 Geofluids


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

e

Kaolinite

Calcite

Oligoclase


Quartz

Dolomite


frac

tion

(b)


0

2

4

6

8

10

pH

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

Ca2+

SiO2(aq)

CO2 (aq) Mg2+


HCO3minus

(c)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(d)

Zone II

Zone I Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(e)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(f)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(g)

Zone II

Zone I

Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(h)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(i)





Geofluids 11

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro


T_50∘CT_67∘CT_80∘C

(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite

T_50∘CT_67∘CT_80∘C

(b)

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


0246810

pH

T_50∘CT_67∘CT_80∘C

HCO3minus

(c)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(d)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(e)


pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

HCO3minus


(f)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(g)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(h)


100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

HCO3minus


(i)






12 Geofluids

Porosity010011010009010007010005010003010001

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(a)

Porosity012915012912501291012907501290501290250129

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(b)


0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)





Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

8 Geofluids



minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


(a)


Calcite

Oligoclase


minus80

minus60

minus40

minus20

0

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


30 yr3 yr 10 yr

minus7E minus 05

minus4E minus 05

minus1E minus 05

(b)

Dolomite


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

00 0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)



(c)



(9)


(10)


Geofluids 9





()0


Salinity (wt)009

Case 12 9Case 13 15











10 Geofluids


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

e

Kaolinite

Calcite

Oligoclase


Quartz

Dolomite


frac

tion

(b)


0

2

4

6

8

10

pH

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

Ca2+

SiO2(aq)

CO2 (aq) Mg2+


HCO3minus

(c)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(d)

Zone II

Zone I Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(e)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(f)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(g)

Zone II

Zone I

Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(h)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(i)





Geofluids 11

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro


T_50∘CT_67∘CT_80∘C

(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite

T_50∘CT_67∘CT_80∘C

(b)

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


0246810

pH

T_50∘CT_67∘CT_80∘C

HCO3minus

(c)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(d)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(e)


pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

HCO3minus


(f)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(g)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(h)


100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

HCO3minus


(i)






12 Geofluids

Porosity010011010009010007010005010003010001

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(a)

Porosity012915012912501291012907501290501290250129

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(b)


0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)





Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

Geofluids 9





()0


Salinity (wt)009

Case 12 9Case 13 15











10 Geofluids


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

e

Kaolinite

Calcite

Oligoclase


Quartz

Dolomite


frac

tion

(b)


0

2

4

6

8

10

pH

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

Ca2+

SiO2(aq)

CO2 (aq) Mg2+


HCO3minus

(c)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(d)

Zone II

Zone I Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(e)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(f)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(g)

Zone II

Zone I

Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(h)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(i)





Geofluids 11

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro


T_50∘CT_67∘CT_80∘C

(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite

T_50∘CT_67∘CT_80∘C

(b)

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


0246810

pH

T_50∘CT_67∘CT_80∘C

HCO3minus

(c)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(d)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(e)


pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

HCO3minus


(f)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(g)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(h)


100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

HCO3minus


(i)






12 Geofluids

Porosity010011010009010007010005010003010001

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(a)

Porosity012915012912501291012907501290501290250129

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(b)


0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)





Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

10 Geofluids


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

e

Kaolinite

Calcite

Oligoclase


Quartz

Dolomite


frac

tion

(b)


0

2

4

6

8

10

pH

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

Ca2+

SiO2(aq)

CO2 (aq) Mg2+


HCO3minus

(c)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(d)

Zone II

Zone I Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(e)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(f)


100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity


(g)

Zone II

Zone I

Zone III

100 100001 1 1000010

Radial distance (m)

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite


minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

(h)


0

2

4

6

8

10

pH

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1 pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


HCO3minus

(i)





Geofluids 11

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro


T_50∘CT_67∘CT_80∘C

(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite

T_50∘CT_67∘CT_80∘C

(b)

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


0246810

pH

T_50∘CT_67∘CT_80∘C

HCO3minus

(c)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(d)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(e)


pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

HCO3minus


(f)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(g)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(h)


100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

HCO3minus


(i)






12 Geofluids

Porosity010011010009010007010005010003010001

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(a)

Porosity012915012912501291012907501290501290250129

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(b)


0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)





Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

Geofluids 11

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro


T_50∘CT_67∘CT_80∘C

(a)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Ca-smectite

Dolomite

T_50∘CT_67∘CT_80∘C

(b)

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+


0246810

pH

T_50∘CT_67∘CT_80∘C

HCO3minus

(c)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(d)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n

Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(e)


pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

HCO3minus


(f)

100 100001 1 1000010

Radial distance (m)

01260

01261

01262

01263

01264

01265

Poro

sity

Zone II

Zone I

Zone III


(g)


100 100001 1 1000010

Radial distance (m)

minus00012

minus00009

minus00006

minus00003

00000

00003

00006

Chan

ges i

n m

iner

al v

olum

efr

actio

n Calcite

Oligoclase

Na-smectite

Dolomite

Ca-smectite


(h)


100 100001 1 1000010

Radial distance (m)

The c

once

ntra

tion

of aq

ueou

ssp

ecie

s (m

olk

g)

1Eminus4

1Eminus6

1Eminus3

1Eminus5

001

01

10

1

0

2

4

6

8

10

pH

pH

Ca2+

SiO2(aq)

CO2 (aq)

Mg2+

HCO3minus


(i)






12 Geofluids

Porosity010011010009010007010005010003010001

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(a)

Porosity012915012912501291012907501290501290250129

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(b)


0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)





Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

12 Geofluids

Porosity010011010009010007010005010003010001

minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(a)

Porosity012915012912501291012907501290501290250129

0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(b)


0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

(c)





Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

Geofluids 13

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

281E minus 15

2812E minus 15

2814E minus 15

2816E minus 15

2818E minus 15

(a)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0D

epth

from

the t

op (m

)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

658E minus 15

6584E minus 15

6588E minus 15

6592E minus 15

6596E minus 15

66E minus 15

6604E minus 15

(b)

Permeabi0

minus80

minus60

minus40

minus20

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


minus80

minus60

minus40

minus20

0

Dep

th fr

om th

e top

(m)


10 yr3 yr 30 yr

599E minus 15

6002E minus 15

6014E minus 15

6026E minus 15

6038E minus 15

605E minus 15

6062E minus 15

(c)






14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

14 Geofluids


0100101000

012910129001289

00

02

04

06

08

10

Supe

rcrit

ical

2sa

tura

tion



012600126101262012630126401265

Poro

sity


10 100 1000 10000








4 Conclusions



Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

Geofluids 15







Acknowledgments



References














16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

16 Geofluids

































Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in

Geofluids 17






















Mining


Journal of









Journal of




Advances in











Geology Advances in








Mining


Journal of









Journal of




Advances in











Geology Advances in

numerical investigation into the impact of co -water-rock...

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