storage in subsurface pore space: monitoring co...
TRANSCRIPT
Storage in Subsurface Pore Space:Monitoring CO2 Storage
Thomas M. (Tom) DaleyLawrence Berkeley National Laboratory
Workshop on Geological Capture and Sequestration of CarbonNov. 28, 2017 Stanford University
Outline
• Goals of Monitoring • Types of Monitoring
– direct/indirect, qualitative/quantitative• Brief Status of Seismic Monitoring technology
– Issues with quantitative analysis– Need for Integrating Multi‐Physics
• Issues and R&D needs
Monitoring: What, When, Where, Why?
after Peters 2007
after Mathieson et al., 2010
Need to have goals to guide decisions!
Choosing Monitoring
When and Why to Monitoring
Goals of Monitoring• Performance Assurance
– Injection and growth of plume are progressing as expected (modeled)– Expect quantitative monitoring to compare to models
• Regulatory Compliance– Varies with location, e.g. US EPA requires “systems that detect leakage of
CO2 from either the containment reservoir or away from the storage site”• Risk Reduction
– Will overlap with Performance Assurance monitoring– “understanding risk‐driven monitoring uncertainty will require dedicated
experiments to probe and test monitoring of actual leakage scenarios.” (Harbert, et al., 2016)
• Public Assurance– Private water wells, induced seismicity, atmospheric sampling
Types of Monitoring• Site Characterization vs Monitoring
– Characterization typically implies a static ‘snapshot’ of properties, but needs to be an iterative process including monitoring to capture dynamics
– Optimal monitoring design needs accurate characterization, but changes can be detected without accurate static characterization
• Direct and Indirect Monitoring– Direct => Pressure, geochemical sampling
• Key to confirming interpretations; Limited to specific locations, typically in boreholes– Indirect => Seismic reflection; ground deformation; electrical conductivity
• Most cost effective; Can cover large areas, typically with decreasing resolution at distance
• Quantitative and Qualitative Monitoring– Quantitative => e.g. CO2 mass in a given volume– Qualitative => e.g. detection of CO2 at unknown saturation
• Need to understand differences when discussing/designing monitoring
Seismic Monitoring • Seismic monitoring is the ‘workhorse’. Advanced technology from O&G industry• Quantitative analysis for CO2 saturation is still developing and problematic.• Basic Seismic Rock Physics – We measure wave velocity (Vp), we want gas saturation (Sg);
– In conventional analysis they are linked by the bulk modulus for saturated rock (Ksat), rock matrix (K*), matrix minerals (K0 ) combined fluid ( Kfl), along with porosity Φ.
– Gassmann Substitution: VP ‐> Ksat; Ksat ‐> Kfl; Kfl ‐> Sg (e.g. Smith, et al, 2003)
Many assumptions here includingstatic matrix properties, uniformfluid mixing, homoenegenity, no rock‐fluid interaction
Seismic Monitoring can be very sensitive, but…
• Frio Project had ‘too large’ of response – why?
Daley, et al., 2006
Seismic Issue: Uncertainty in Fluid Mixing
• As we increase frequency to improve resolution, the rock physics becomes more uncertain
• Uniform vs Patchy Saturation (wavelength dependent)
• Also sensitive to P‐T conditions, brine properties, anisotropy, dissolution into brine and any other gas saturation (e.g. CH4)
0 0.2 0.4 0.6 0.8 1−500
−450
−400
−350
−300
−250
−200
−150
−100
−50
0
CO2 Saturation (fraction)
V p (m
/s)
[A]
WDO, 15 cm patchWDO, 2.5 cm patchGassmann + ReussGassmann + VoigtBGH
Daley, et al., 2011
Issue: Geochemical Alteration• Mainly issue in carbonates, but also silicic rocks• “Two main changes are involved: porosity enhancement due to dissolution, and loss of granular microstructure “
Time‐Lapse CT ScanOf Fountainebleau sandstone
From Vanorio, et al., 2011.
Frio Frame Change Can Explain Data• Frame Cementation Change inferred from Seismic data, invalidates Gassmann assumption
– Need to consider geochemical alteration and,– Need to have Multi‐Physics monitoring data: both P‐wave and S‐wave to resove change
Al Hosni, et al., 2015
Frio Cementation Models
Change in Vp at Frio increased by geochemistry
MatrixCementAlteration(0.1 to 0.01%)
R&D Needs• Field Experiments
– Larger Scale – Gigatonne?– Integrate multi‐scale field measurements – Test leakage detection and mitigation
• Understand Importance/Impact of monitoring wells– Cost/Benefit of monitoring wells – how many and where?
• Multi‐physics to improve quantification– Active‐source seismic is key tool, but has quantification limits and
issues• Uncertain rock physics• Geochemical impacts
Satellite (InSAR)
Surface Seismic
Borehole Seismic VSP, Crosswell
Well Logs
Core Tests
~10-1 to 10 m~10-3 to 1 m ~10 to 103 mApproximate Spatial Resolution
Scal
e of
Inve
stig
atio
n Regional~10 to 104 m
Local~10-2 to 102 m
Lab~10-4 to 10-1 m
Need Multiple Scales of Investigation
Need Boreholes
Boreholes are key for direct monitoring, especially pressure (a high value parameter)
Need Multi‐Physics: Example ‐ Seismic and EM
• Seismic alone has uncertainty at high CO2 saturation and uncertainty in rock physics interpretation
• EM (conductivity) has strong sensitivity at all saturations and a single rock physics model (Archie’s relation) and should complement seismic for estimating saturation within plume
• Ideally combine seismic, EM and flow models in joint inversion for CO2
Xue, et al., 2009
Boundary And LeakageDetection
Plume BodyMonitoring
Saturation fromArchie’s Relation
3 Specific Field Experiments Needed
• Shallow Groundwater– Gas and Dissolved CO2
detection
• Intermediate Depth – Leakage, Gas‐Phase
detection
• Deep Fault/Fracture Flow– Supercritical flow in
fractures– Induced seismicity
• Need to test mitigation in all three
Shallow has limited testing (ZERT, Plant Daniel); Intermediate has one new test (CaMI); No deep fracture/fault tests (one planned at Otway; one unintended at In Salah)
Importance of Fault/Fracture Leakage Field Studies
• Field projects to date has demonstrated safe storage, but we need to study/understand leakage pathways
• Faults and fracture zones have potentially high flow
• Recent work shows uncertain link between fault permeability change and pressure (for brine)
• Fault Leakage can occur below the Critical Stress StatePermeability change may occur before or without reactivation. Results from an in situ fault reactivation experiment, Guglielmi, et al, 2017
• Permeability depends on Stress + Local Strain or Strain Rate
Permeability variations associated with fault reactivation in a claystone formation (Jeanne, et al, in review).
In Salah Fracture ZoneZhang, et al, 2015
Summary• Need to understand the goals of monitoring to
drive R&D• Need to understand the types of monitoring, don’t
compare apples to orangesdirect/indirect, qualitative/quantitative
• Seismic is key technology but need to consider geochemical impacts to improve quantification
• Field Experiments at Larger Scale – Gigatonne?– Need to test leakage and mitigation scenarios– Need indirect, quantitative monitoring
• Understand Importance/Impact of monitoring wells
– Key for direct monitoring, especially pressure• Need Multi‐physics to improve quantification
– Use/integrate Shear‐waves, electrical/EM measurements, pressure, deformation
And a final comment:• How often to monitor – continuous?
• O&G Industry moving to permanent reservoir monitoring (PRM)
• New technology (e.g. fiber optics) is decreasing cost of permanent monitoring
Appendix:Recent Industry R&D Review
Workshop Summary Questions and Important R&D Topics
• Are we ready for Gigatonne scale up?• How do we bring monitoring costs down?• Have we demonstrated minimum CO2 visible/detectable?• Why did some projects fail? • Improve seismic technology: Can DAS replace geophones, for VSP, MEQ, surface?• Need uncertainty quantification for saturation estimates? • Gravity monitoring may be good for leakage (higher density contrast and shallower)• Discussion: Leakage: Affects on green house gas storage; • Question: what do we do with a leak?• Can we use shallow leakage experiments to test mitigation ?• Discussion: Impacts of Induced seismicity• Question: Can seismic separate pressure and saturation? How, and what data is
needed?• Question: Should MEQ monitoring be required?• Question: on use of nanoparticles• Question: How to best use InSAR – other information needed?
Look at use of controlled leakage sites for how to stop leakage
Evaluate detection thresholds
Summarize detection levels from field experiments
Use of multi‐physics, how to combine
Using joint inversion, multiple approaches to improve quantification
Need more measurements, how to make them less expensive
Use of permanent buried systems, what is best use
Move to integrating monitoring with decision making, for efficiency
Uncertainty quantification, rock physics at field scale, spatial and temporal variability
Need for lab measurements, especially electrical properties
Consider change in properties due to contaminants in CO2 stream or subsurface, can they be used as tracer
Dissolution of co2, need geochemical research on lifetime of co2, does shallow dissolution add to trapping
Pressure monitoring above zone, monitoring of secondary storage
How do we assess value of information, more work on assessing value of monitoring techniques
Fault reactivation and understanding process and how to monitor , what is flow mechanism in fault‐fractures
Induced seismicity with large scale injection
How to measure bicarbonate in water – use of fiber
The workshop had a general discussion of status and R&D topics for geophysical monitoring of CO2. Examples include: ‘Are we ready for gigatonne scale up?’, ‘How do we bring monitoring costs down?’, ‘Can we use shallow leakage experiments to test mitigation?’ and a discussion of induced seismicity issues.
The general feeling is that current technologies exist for CO2 injection characterization and monitoring, although technical and economic challenges remain. Permanent buried seismic arrays should help the industry to reach the required levels of accuracy. From Verliac, et al, First Brea, in press.
ReferencesAl Hosni, M Vialle, S. , Gurevich, B. , Daley, T. M., 2016, Estimation Of Rock Frame Weakening Using Time‐Lapse Crosswell: The Frio Brine Pilot Project, Geophysics, 81, B235–B245, DOI: 10.1190/GEO2015‐0684.1
Börner, J.H., Herdegen, V., Repke, J.‐U. and Spitzer, K., “The electrical conductivity of CO2–bearing pore waters at elevated pressure and temperature: A laboratory study and its implications in CO2 storage monitoring and leakage detection,” 2015, Geophys. J. Int., 203
Daley, T. M., L. Myer, J. E. Peterson, E. L. Majer, and G. M. Hoversten, 2008, Time‐lapse crosswell seismic and VSP monitoring of injected CO2 in a brine aquifer: Environmental Geology, 54, 1657–1665, doi: 10.1007/ s00254‐007‐0943‐z. Daley, Thomas M., Jonathan B. Ajo‐Franklin, Christine Doughty, (2011). Constraining the reservoir model of an injected CO2 plume with crosswell CASSM at the Frio‐II brine pilot, International Journal of Greenhouse Gas Control, 5, pp. 1022‐1030, DOI information: 10.1016/j.ijggc.2011.03.002Jeanne, P., Y.Guglielmi, J.Rutqvist, C.Nussbaum and J. Birkholzer (in review) Permeability variations associated with fault reactivation in a claystone formation Investigated by field experiments and numerical simulations, In review at Journal of Geophysical Research.Guglielmi, Y., J.Birkholzer, J.Rutqvist, P.Jeanne, C.Nussbaum (2017) Can fault leakage occur before or without reactivation. Results from an in situ fault reactivation experiment at Mt Terri. Energy Procedia114, 3167 – 3174.
Harbert, W., T M. Daley, G Bromhal, C Sullivan, and L Huang, 2016, Progress in monitoring strategies for risk reduction in geologic CO2 storage, International Journal of Greenhouse Gas Control, pp. 260‐275. DOI: 10.1016/j.ijggc.2016.05.007
Mathieson, A., Midgley, J., Dodds, K., Wright, I., Ringrose, P., and Saoul, N., 2010. CO2 sequestration monitoring and verification technologies applied at Krechba, Algeria. Leading Edge 29 (2), 216–222.Nakagawa, Seiji, Timothy J. Kneafsey, Thomas M. Daley, Barry M. Freifeld, and Emily V. Rees, 2013, Laboratory seismic monitoring of supercritical CO2 flooding in sandstone cores using the Split Hopkinson Resonant Bar technique with concurrent x‐ray CT imaging, Geophysical Prospecting, 61, 254–269.
Peters, D., 2007. CO2 geological storage‐methodology and risk management process. NHA Hydrogen Conference March 20, 2007. Smith, T. M., Sondergeld, C.H., and Rai, C. S., (2003). Gassmann fluid substitutions: A Tutorial, Geophysics, 68, p430‐440.
Vanorio, T., G. Mavko, S. Vialle, and K. Spratt, (2010). The rock physics basis for 4D seismic monitoring of CO2 fate: Are we there yet?: The Leading Edge, 29, 156–162.Vanorio, T., Nur, A., and Ebert Y., 2011, Rock physics analysis and time‐lapse rock imaging of geochemical effects due to the injection of CO2 into reservoir rocks, GEOPHYSICS. VOL. 76, 5, 10.1190/GEO2010‐0390.1
Xue, Z.; J. Kim, S. Mito and K. Kitamura, T. Matsuoka, 2009, Detecting and Monitoring CO2 with P‐wave Velocity and Resistivity from Both Laboratory‐ and Field Scales, SPE International Conference on CO2 Capture, Storage, and Utilization, SPE 126885.
Zhang, R., Vasco, D., Daley, T.M., 2015, Characterization of a fracture zone using seismic attributes at the InSalah CO2 storage project, Interpretation, SM37‐46. DOI:10.1190/INT‐2014‐0141.1.
Issue: Geochemical Alteration• Geochemical alteration can be first order affect, especially on carbonates• Invalidates Gassmann assumption of constant frame properties and constant porosity
With multi‐physics data (e.g. P‐ and S‐wave seismic data) we can reduce uncertainty
Vanorio, et al., 2010
P‐Wave S‐Wave