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Precambrian Research xxx (2007) xxx–xxx

Noble gas and halogen constraints on regionally extensive mid-crustalNa–Ca metasomatism, the Proterozoic Eastern Mount Isa Block, Australia

M.A. Kendrick a,∗, T. Baker b, B. Fu b,1, D. Phillips a, P.J. Williams b

a Predictive Mineral Discovery Cooperative Research Centre (pmd*CRC) at the School of Earth Sciences,The University of Melbourne, Victoria 3010, Australia

b School of Earth Sciences, James Cook University of North Queensland, Townsville, Queensland 4811, Australia

Received 5 June 2006; received in revised form 16 January 2007; accepted 13 August 2007

bstract

Fluid inclusions in late-Isan quartz veins associated with regional Na–Ca alteration (albitisation), in the Mary Kathleen Fold Belt and theloncurry District of the Eastern Mt Isa Block, have been analysed for naturally occurring and neutron produced isotopes of Ar, Kr and Xe. Theoble gases have been extracted using a thermal decrepitation procedure that enables partial deconvolution of the different fluid inclusion types,ncluding variably saline aqueous, liquid carbon-dioxide and mixed aqueous-carbonic varieties.

The variably saline (<5–65 wt%) aqueous fluid inclusions dominate and have 40Ar/36Ar values of less than 2700 in most of the samples fromcross the region. These fluid inclusions have extremely variable molar Br/Cl values of 0.3–4 × 10−3 and I/Cl values of 0.2–35 × 10−6, and theuids are interpreted to represent sedimentary formation waters derived from the upper crust that have dissolved variable quantities of halite (orcapolite) to achieve their ultra-high salinity.

Fluid inclusions in a sample from the Snake Creek anticline in the Cloncurry District have the highest 40Ar/36Ar value of ∼25,000 demonstratingdeep magmatic or metamorphic fluid origin in this case. A magmatic origin is favoured because this fluid is very similar to a fluid involved in

ron-Oxide-Copper-Gold (IOCG) mineralization at Ernest Henry that was also interpreted to have a magmatic origin, and because the aqueousuid inclusions have Br/Cl of ∼1–2 × 10−3 and I/Cl of ∼10 × 10−6 that are similar to mantle-derived igneous rocks.Carbon-dioxide fluid inclusions dominate samples from the Knobby Quarry in the Mary Kathleen Fold Belt and have a maximum 40Ar/36Ar

alue of 6000–7000. These fluid inclusions are estimated to have a 36Ar concentration of 1–4 ppb, that is similar to the range determined forqueous fluid inclusions in all the other samples. In addition, aqueous and carbonic fluid inclusions in all the samples have similar 129Xe/36Ar plus4Kr/36Ar values that are unfractionated, and close to the air—Air Saturated Water (ASW) range.

These data are interpreted to indicate an independent and dominantly metamorphic origin for CO2, and the presence of mixed aqueous-carbonicuid inclusions are attributed to fluid mixing and/or mingling, rather than fluid unmixing. However, the data do not preclude the presence of ainor magmatic CO2 component in the samples from the Knobby Quarry.Fluid inclusions in most of the samples from the Mary Kathleen Fold Belt have higher Br/Cl and I/Cl values, higher 36Ar concentrations and

ower maximum 40Ar/36Ar values than fluid inclusions in samples from the Cloncurry District. This suggests Na–Ca alteration in these differentarts of the Eastern Mt Isa Block occurred independently. However, fluid inclusions associated with Na–Ca alteration in the Cloncurry District

Please cite this article in press as: Kendrick, M.A., et al., Noble gas ametasomatism, the Proterozoic Eastern Mount Isa Block, Australia, Preca

ave a very similar composition to fluid inclusions in IOCG mineralization-stage quartz veins from Ernest Henry.These data are therefore compatible with a genetic relationship between regional Na–Ca alteration and IOCG mineralization in the Cloncurry

istrict. In both cases the ultra-saline hydrothermal fluids had a dominant origin from sedimentary formation water, but are interpreted to containmagmatic component sourced from the late-Isan Williams-Naraku Batholiths which may have driven fluid convection.2007 Elsevier B.V. All rights reserved.

eywords: Fluid inclusions; Regional alteration; Albitisation; IOCG; Metallogenesis

∗ Corresponding author.E-mail address: [email protected] (M.A. Kendrick).

1 Present address: Predictive Mineral Discovery Cooperative Research Centrepmd*CRC) at the School of Earth Sciences, The University of Melbourne,ictoria 3010, Australia.

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301-9268/$ – see front matter © 2007 Elsevier B.V. All rights reserved.oi:10.1016/j.precamres.2007.08.015

; Fluid convection

. Introduction

nd halogen constraints on regionally extensive mid-crustal Na–Cambrian Res. (2007), doi:10.1016/j.precamres.2007.08.015

The Eastern Fold Belt of the Proterozoic Mount Isa Inlierf northeast Australia preserves a remarkably extensive recordf mid-crustal hydrothermal alteration and metasomatism (deong and Williams, 1995; Oliver, 1995; Williams, 1998; Xu,

dx.doi.org/10.1016/j.precamres.2007.08.015

mailto:[email protected]


ARTICLE IN PRESS+ModelPRECAM-2902; No. of Pages 20

2 M.A. Kendrick et al. / Precambrian Research xxx (2007) xxx–xxx

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ig. 1. Simplified geological map of the Eastern Fold Belt of the Mt Isa Inlier. Tistrict. The outcrop of regional Na–Ca alteration is somewhat schematic, but i

fter Page and Sun (1998), Gauthier et al. (2001), Rubenach et al. (2001), Olive

000; Oliver et al., 2004; Mark et al., 2004). Multiple phases ofegionally pervasive Na–Ca alteration (albitisation) are observedn both the Mary Kathleen Fold Belt and the Cloncurry Dis-rict and are locally overprinted by potassic alteration associatedith Iron-Oxide-Copper-Gold (IOCG) mineralization (Fig. 1;e Jong and Williams, 1995; Oliver, 1995; Adshead et al.,998; Baker, 1998; Rubenach and Barker, 1998; Williams, 1998;ubenach and Lewthwaite, 2002; Mark et al., 2004, 2006a;liver et al., 2004).Much of the regional alteration, and the majority of the IOCG


eposits, formed during the latter half of the ∼1.6–1.5 Ga Isanrogeny, broadly coincidental with intrusion of the Williams-araku Batholiths (e.g. Page and Sun, 1998; Oliver et al., 2004;ark et al., 2006a). Nonetheless, the origin of regional Na–Ca

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grim Fault separates the Mary Kathleen Fold Belt (MKFB), from the Cloncurryd on similar maps in Mark et al. (2004) and Oliver (1995). Age constraints arel. (2004), Mark et al. (2006b) and Rubenach et al. (this issue).

lteration remains controversial and is of special interest becauset is seen in a number of terranes that host IOCG deposits andas been inferred to be a part of a larger metallogenic systemWilliams, 1994; Barton and Johnson, 1996; Hitzmann, 2000;ollard, 2001; Oliver et al., 2004).

In this study, we utilize the noble gases and halogens as fluidracers to test if fluids associated with regional Na–Ca alterationad similar origins in the Mary Kathleen Fold Belt and the Clon-urry District (Fig. 1). In addition, we test whether the alterationuids had similar origins to the mineralizing fluids responsible


or IOCG mineralization (see Fisher et al., 2005; Kendrick et al.,006b, 2007). The noble gases and halogens are ideally suitedo determining fluid origins in IOCG terranes where the prin-ipal uncertainties are the extent of halite dissolution and the


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ARTICLERECAM-2902; No. of Pages 20

M.A. Kendrick et al. / Precam

elative importance of primary magmatic fluids versus sedimen-ary formation water and/or metamorphic volatiles (Barton andohnson, 1996; Hitzmann, 2000; Perring et al., 2000; Baker etl., 2001; Pollard, 2001; Mark et al., 2004, 2006a; Oliver et al.,004).

Magmatic fluids are characterized by a limited range in Br/Clnd I/Cl and can have 40Ar/36Ar values of tens of thousands, ifourced from the deep crust or mantle (Burnard et al., 1997;endrick et al., 2001, 2007; Ballentine et al., 2002). The halo-ens are strongly fractionated by interaction with halite, whichreferentially excludes Br and I, meaning that halite dissolutiontrongly reduces fluid Br/Cl and I/Cl values (Zherebtsova andolkova, 1966; Holser, 1979; Fontes and Matray, 1993; Hanor,994). Upper crustal sedimentary formation waters typicallyave 40Ar/36Ar values of less than ∼2000 and the modern atmo-phere, or Air Saturated Waters (ASW—seawater or meteoricater) have the lowest 40Ar/36Ar values of ∼296 (Kendrick et

l., 2002a,b; Ozima and Podosek, 2002). Together, the nobleases and halogens can also provide information on some meta-orphic processes: prograde fluids formed by devolatilisation

f crystalline basement are likely to have high (magmatic-like)0Ar/36Ar values, low 36Ar concentrations and low salinity (e.g.20 wt%; Bennett and Barker, 1992; Phillips and Powell, 1993;endrick et al., 2006a). Whereas lower 40Ar/36Ar values (i.e.2000) could result from devolatisation of 36Ar-rich sedimen-

ary (or meta-sedimentary) rocks (Kendrick et al., 2006a, 2007).n addition at low water-rock ratios, the fluids’ salinity, 36Aroncentration and Br/Cl values could be elevated by retrogradeydration reactions (Bennett and Barker, 1992; Svensen et al.,001; Kendrick et al., 2006a).

Finally, because the halogens are extracted from aqueousuid inclusions, and the noble gases are extracted from bothqueous and carbonic fluid inclusions (Kendrick et al., 2006b,007), these data are complementary to stable isotope studiesC, O, H) that seek to constrain the origin of the major volatileomponents directly (e.g. Oliver et al., 1993; Mark et al., 2004;arshall et al., 2006). However, unlike stable isotopes, the noble

ases are strongly incompatible in crustal minerals meaning thathey preferentially enter the fluid phase and do not undergo iso-opic exchange (Ballentine et al., 2002; Ozima and Podosek,002). As a result the fluid noble gas concentration is increaseduring wall rock interaction and helps determine the extent ofall rock interaction and/or phase separation, as well as therigin of the primary fluid (Kendrick et al., 2006a).

. Geology

.1. Metamorphism and magmatism

Peak metamorphism in the Eastern Fold Belt occurred syn-hronously with E-W shortening (D2) at 1595–1575 Ma (Fosternd Rubenach, 2006). Amphibolite grade rocks predominate inhe Mary Kathleen Fold Belt (Oliver et al., 1992), but elsewhere


eak metamorphic grades increase from greenschist to upper-mphibolite facies in a generally southeasterly direction (Fosternd Rubenach, 2006). Meta-sedimentary rocks include the760–1720 Ma evaporite-rich calc-silicate supracrustal rocks of

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he Corella Formation and equivalents (cover sequence 2), whichre associated with intercalated metavolcanic rocks and intru-ions, and the younger 1680–1650 Ma siliclastic-rich rocks ofhe Soldiers Cap Group (cover sequence 3; Blake, 1987; Pagend Sun, 1998).

The regionally extensive Williams-Naraku Batholithsntruded during two phases of post-peak metamorphic

agmatism (Fig. 1; Page and Sun, 1998). Granodiorite-tonalite-rondhjemite suite intrusions were emplaced close to theloncurry Fault around ∼1550 Ma, followed by intrusion of theolumetrically most abundant phases of the Williams-Narakuatholiths between ∼1540 Ma and ∼1490 Ma (Fig. 1; Wybornt al., 1988; Page and Sun, 1998). These late- to post-D3 gran-toids probably formed in an intra-continental/back arc setting,hey have extremely variable compositions and have been vari-bly classified as I- or A-type (Wyborn et al., 1988; Page andun, 1998; Pollard et al., 1998; Wyborn, 1998; Mark, 2001).

Melt generation is considered to have taken place in thelagioclase stability field at a depth of ≤25–30 km and mayave been triggered by the introduction of mantle melts in aafic underplate (Page and Williams, 1988; Wyborn et al., 1988;acCready et al., 1998; Pollard et al., 1998; Mark, 2001). At

he current level of exposure, the more mafic phases, which havepossible mantle-origin, include hornblende-diopside mon-

onites and quartz diorites (Wyborn, 1998; Mark, 1999). Theore dominant felsic phases with 65–77 wt% SiO2, which

nclude K-rich porphyritic monzodiorite, monzogranite, gran-diorite and granite, formed by re-melting of multiply reworkedaleoproterozoic igneous rocks with depleted mantle Sm-Ndodel ages of ∼2.2–2.3 Ga (Wyborn et al., 1988; Page and Sun,

998; Wyborn, 1998; Mark, 2001).

.2. Post-peak metamorphic Na–Ca alteration

Zones of intense Na–Ca alteration have been mappedhroughout the Eastern Fold Belt (Fig. 1) and are now known toave formed in several discrete episodes (Rubenach and Barker,998; Rubenach and Lewthwaite, 2002; Oliver et al., 2004;ubenach et al., this issue). The focus of this study, is the late-

san post-peak metamorphic albitisation that is associated with3 shear zones that overprint the main metamorphic fabric (de

ong and Williams, 1995; Oliver, 1995). The Na–Ca alterations most intensely developed in calc-silicate rocks which hosteins and breccias rich in albitic-plagioclase, amphibole, plusalcite and commonly contain clinopyroxene, magnetite, quartz,capolite, biotite, titanite or apatite (Oliver et al., 1993, 2004;liver, 1995; Mark et al., 2004; Marshall et al., 2006). Calc-

ilicate rocks are most abundant in the Mary Kathleen Fold Belt,here approximately 20% of the exposed rocks are affected by

ntense Na–Ca alteration and giant calcite ‘pods’ 100’s of metresn size have been quarried (Oliver, 1995; Oliver et al., 2004).

etapelite-hosted alteration tends to be more sodic in charac-er with more abundant albite, fewer calcic phases and only rare


uartz (de Jong and Williams, 1995; Rubenach and Barker, 1998;ubenach and Lewthwaite, 2002).

Limited U–Pb ages from hydrothermal titanites, formed dur-ng the dominant phase of Na–Ca alteration in both the Mary


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athleen Fold Belt and the Cloncurry District, and zircons inlbitised granites, confirm that much of the alteration occurredfter peak-metamorphism at ∼1530–1520 Ma (Oliver et al.,004; Mark et al., 2006b). However, a single titanite fromhe Knobby Quarry calcite ‘pod’ (Fig. 1) gave an earlier agef ∼1555 Ma, reflecting either multiple phases of post-peak-etamorphic Na–Ca alteration or that albitisation had an earlier

nset in the Mary Kathleen Fold Belt than in the Cloncurry Dis-rict (Oliver et al., 2004). Due to the channelised nature of fluidow, earlier phases of pre-Isan and peak-metamorphic albitisa-

ion are preserved in isolated pockets of unaltered rock (Oliver,995). For example, Na–Ca alteration at the Osborne Mine hasU–Pb titanite age of ∼1595 Ma, that is within error of IOCGineralization and peak metamorphism at this locality (Gauthier

t al., 2001; Rubenach et al., 2001, this issue). Pre-Isan andeak-metamorphic albitisation are also preserved in parts of theoldiers Cap Group and dominate meta-pelites in the Snakereek Anticline (Rubenach and Barker, 1998; Rubenach andewthwaite, 2002; Rubenach et al., this issue).

Nonetheless, the dominant district-wide Na–Ca alteration at1530–1520 Ma overlaps intrusion of the volumetrically most

ignificant phases of the Williams-Naraku Batholiths at 1540–490 Ma (Page and Sun, 1998) and the majority of IOCGeposits with ages of 1540–1505 Ma (Mark et al., 2006a). Forxample, IOCG mineralisation at Ernest Henry, regional Na–Calteration, and intrusion of the 15 km distant Mt Margaret gran-te, all occurred close to ∼1525 Ma (Fig. 1; Page and Sun, 1998;

ark et al., 2006b). A possible relationship between regionala–Ca alteration and magmatism in the Cloncurry District is

urther supported by the occurrence of limited granitoid-hosteda–Ca veins and breccias that are infilled by both crystallineelt and hydrothermal precipitates (Mark and Foster, 2000;ark et al., 2004).

.2.1. Petrologic and isotopic constraintsCalc-silicate mineral equalibria, calcite–dolomite geother-

ometry and oxygen isotope geothermometry on quartz,agnetite, albite and amphibole indicate alteration occurred

t 400–600 ◦C (Mark and Foster, 2000; Oliver et al., 2004).he best constraint on pressure comes from quartz-hostedigh-density CO2 fluid inclusions that, at 400–600 ◦C, indicatentrapment at 200–450 MPa (Oliver et al., 2004; Fu et al., 2003,004; see also de Jong and Williams, 1995).

Previous Br/Cl analyses of two Knobby Quarry quartz sam-les, obtained from scapolite bearing veins, gave near seawaterr/Cl values (Heinrich et al., 1993), that are consistent with,ut do not prove a magmatic fluid origin. More extensivemphibole analyses indicate that, relative to V-SMOW, fluidsesponsible for vein and breccia-hosted Na–Ca alteration inhe Cloncurry District had �18Ofluid of 8.0–12.8‰ and �Dfluidn the range −29 to −99‰ (Mark et al., 2004). Relative to-SMOW and PDB, carbonate veins throughout the Easternold Belt have �18Ocarbonate of 9–18‰ and �13Ccarbonate in the


ange −0.6 to −7‰ (Oliver et al., 1993; Marshall et al., 2006).hese values are intermediate between marine meta-carbonatesuch as the Corella Formation (�18Ocarbonate = 8–20.5‰ and13Ccarbonate = +2 to −3‰) and calcite in graphitic meta-

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PRESSResearch xxx (2007) xxx–xxx

ediments of the Soldiers Cap Group (�18Ocarbonate = 9–16‰nd �13Ccarbonate = −2 to −13‰; (Oliver et al., 1993; Marshall etl., 2006). Organic carbon preserved as graphite in black shaleslose to the Dugald River Zn–Pb deposit has an even lower �13Cf −22 to −35‰ (Dixon and Davidson, 1996).

Together the stable isotope data are interpreted to indicatepen system behaviour with an external fluid source (Oliver etl., 1993; Mark et al., 2004; Marshall et al., 2006). Traditionally,magmatic fluid origin has been preferred, largely because of

he possible availability of such fluids from the Williams-Narakuatholiths (Mark et al., 2004), and because the central parts of

he largest veins and calcite pods in the Mary Kathleen Fold Belt,nterpreted to be least affected by wall rock interaction, preservehe most igneous-like �18O and �13C values (Oliver et al., 1993;

arshall et al., 2006). However, the stable isotope data are alsoompatible with sedimentary formation waters or metamorphicuids derived from outside of the Corella Formation that havequilibrated with igneous rocks or homogenized the isotopicignature of several rock types (Oliver et al., 1993; Mark et al.,004; Marshall et al., 2006).

.3. Samples

Thirteen quartz vein samples were selected from seven local-ties at which Na–Ca alteration has been documented previously,nd areas with a potassic overprint were avoided (Fig. 1; Olivert al., 1993, 2004; Oliver, 1995; Xu, 2000; Rubenach andewthwaite, 2002; Mark et al., 2004). The mineralogy of theuartz veins selected is summarized in Table 1.

Quartz was chosen because fluid inclusions associated withegional Na–Ca alteration have good preservation in quartz andave been characterized previously (de Jong and Williams, 1995;liver, 1995; Xu, 2000; Fu et al., 2003, 2004). Furthermore,uartz is well suited to stepped heating experiments used inemi-selective noble gas extraction, meaning that the data cane directly compared with that from IOCG deposits (Fisher etl., 2005; Kendrick et al., 2006b, 2007). However, quartz relatedo Na–Ca alteration in calc-silicate rocks is commonly formedt the edge of veins, and so the trapped fluids may have beenore affected by wall-rock interaction than those trapped in

he central calcite-dominated portions of the largest veins andods (Oliver et al., 1993; Oliver, 1995). In addition, quartz isnly rarely associated with the more sodic alteration typical ofetapelites (de Jong and Williams, 1995; Rubenach and Barker,

998; Rubenach and Lewthwaite, 2002).The quartz veins selected from the Knobby Quarry calcite

od in the Mary Kathleen Fold Belt (Fig. 1) include hydrother-al titanite similar to that dated in other samples from this

ocality (Oliver et al., 2004). However, these samples and otheramples selected from this Fold Belt could be related to post-eak metamorphic Na–Ca alteration at either 1520–1530 Ma or1555 Ma (Oliver et al., 2004) because it has not been possible


o distinguish these alteration phases petrographically.The quartz veins selected in the Cloncurry District from the

loncurry Fault and the Marimo Quarry on the Roxmere StationFig. 1) were foliation discordant and are correlated with the



M.A. Kendrick et al. / Precambrian Research xxx (2007) xxx–xxx 5

Table 1Quartz vein samples associated with regional Na–Ca alteration

Sample Host Rock Vein Mineralogy Aqueous fluid Inclusions Carbonic fluid Inclusions

LV LVD MS CO2 LLc LLcD

Cloncurry districtSnake Creek

02CC47 Soldiers Cap Gp. Qtz + alb ± bio 50–60% 10–20% 20–40% 0–5% 0% 0–1%02CC50 Soldiers Cap Gp. Qtz ± alb 20–40% 30–40% 30–40% 0–10% 0% 0–1%02CC52 Soldiers Cap Gp. Qtz + alb 40–60% 10–20% 20–30% 0% 0% 0%

Roxmere02CC113 Corella Formation Qtz + alb + cc ± mag ± act 40–60% 30–40% 10–20% 0% 0% 0%

Cloncurry Fault02CC143 Soldiers Cap Gp. Qtz 60–70% 10–20% 0–10% 10–20% 0% 0%

Mary Kathleen Fold BeltTribulation Quarry area

02CC05 Corella Formation Qtz + alb + cc + diop 80–95% 5–20% 0% 0% 0% 0%02CC82 Corella Formation Qtz + cc ± alb ± bio 80–90% 10–20% 0% 0% 0% 0%02CC85 Corella Formation Qtz 70–85% 15–30% 0% 0–2% 0–2% 0%

Sunrise quarry02CC62 Corella Formation Qtz + cc ± alb ± bio 55–95% 0–15% 0% 0–40% 0–10% 0%

Knobby quarry02CC108 Corella Formation Qtz + alb + cc + act ± diop ± tit 5–10% ∼10% 0–5% 80–85% 0% 0-2%02CC38 Corella Formation Qtz + alb + cc + act ± tit 10–15% 5–10% 5–10% 70–80% 0% 0–1%

Lime Creek Quarry02CC93 Corella Formation Qtz + cc ± alb ± tour ± act 60–70% 5–10% 0–2% 5–15% 5–15% 0–2%02CC96 Corella Formation Qtz + tour + act + cc ± alb 60–80% 10–30% 0–20% 0–4% 0–4% 0–1%

Abbreviations: Qtz = quartz, alb = albite, bio = biotite, cc = calcite, mag = magnetite, act = actinolite, diop = diopside, tit = titanite, tour = tourmaline. ± denotes phasesthat are present in the vein along strike, but were absent from the sample collected.F multiC

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luid inclusions: LV, 2 phase liquid–vapour; LVD, liquid–vapour + halite; MS,O2 and liquid water with one or more daughter mineral.

1530–1520 Ma ages for albitisation reported for other parts ofhe Cloncurry District (Oliver et al., 2004).

The samples selected from the Snake Creek Anticline havehe most ambiguous significance. This locality is overprinted byost-peak metamorphic albitisation that has an age of ∼1530 Man the edge of the Saxby Granite (Rubenach et al., this issue), buthe area is dominated by relict pre-Isan albitisation (Rubenachnd Barker, 1998; Rubenach and Lewthwaite, 2002). In thisase, the samples were taken from a quartz boudin with possi-le pegmatitic affinity (02CC50), and concordant albite-quartzeins (02CC47 and 02CC52) within psammitic layers. There-ore the predominant secondary fluid inclusions in these samplesould have been trapped either during peak metamorphism,r they could have a similar timing to the post-peak meta-orphic fluid inclusion assemblages preserved at the other

ocalities.

.3.1. Fluid inclusionsThe fluid inclusion assemblages in all our samples have been

tudied in detail. In addition to the four main-types of aque-us and CO2 fluid inclusion recognized previously (de Jong and


illiams, 1995; Oliver, 1995; Xu, 2000), we have observed aignificant number of mixed aqueous-CO2 fluid inclusions. Theain types are defined as: LV, two-phase liquid–vapour; LVD,

alite bearing liquid-vapour; MS, multi-solid liquid–vapour;

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-solid; CO2, liquid CO2 ± N2; LLc, liquid CO2 and liquid water; LLcD, liquid

O2, liquid carbon dioxide; LLc, liquid water and liquid car-on dioxide; and LLcD, liquid water, liquid carbon dioxide andne or more daughter minerals (see Fig. 2 and Table 1).

Fluid inclusion parageneses are difficult to determine due tohe lack of growth zoning and mesothermal nature of quartzeins. However, in many cases LLc or LLcD inclusions cane observed in the same trail as MS, LVD, LV and CO2 fluidnclusions (Fig. 2c). This spatial relationship and the existencef mixed aqueous-carbonic fluid inclusions indicates that thequeous and carbonic fluid phases are intimately associated withne another. The moderately abundant LLc fluid inclusions inhe Lime Creek and Sunrise Quarry samples (Table 1) demon-trate that CO2 was associated with low- as well as high-salinityuids. However, it has not been possible to determine petro-raphically, whether the relationship in these samples resultsrom fluid mixing or unmixing (Fig. 2).

The fluid inclusion assemblages associated with Na–Ca alter-tion hosted by different rock-types throughout the region, areariable, but share some common features (Table 1). As Na–Calteration is commonly multi-stage, it is suggested that the entireuid inclusion assemblage, which is dominated by secondary


uid inclusions in most samples, is representative of the variableuids responsible for Na–Ca metasomatism in different parts of

he region (de Jong and Williams, 1995; Oliver, 1995; Fu et al.,003).




Fig. 2. Quartz hosted fluid inclusions associated with Na–Ca alteration in the Eastern Fold Belt (Table 1). (a) High purity CO2 fluid inclusions and mixed aqueous-CO2

fluid inclusions. (b) Aqueous fluid inclusions. At the top, the heating schedule shows that the LVD fluid inclusion leaked before its final decrepitation at 408 ◦C. (c)E ils. Bl viatio

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xamples of different fluid inclusion types trapped on single fluid inclusion traiquid—bubbles within bubbles, in LLc, LLcD and CO2 fluid inclusions. Abbre

Daughter minerals in the MS and LLcD fluid inclusionsommonly include halite and sylvite plus various iron-rich andnidentified solid phases (Fig. 2a and b). MS fluid inclusionsave total homogenization temperatures as high as 550 ◦C,ndicating total salinity of up to ∼65 wt% NaCl eq. LVDuid inclusions have total homogenization temperatures of70–300 ◦C corresponding to salinities of between ∼30 and0 wt% NaCl eq. Most LV fluid inclusions have homogenizationemperatures of 100–200 ◦C (Fu et al., 2003), but some exhibit

etastability and do not re-nucleate a vapour phase after heat-ng. Consequently, we do not distinguish monophase aqueousuid inclusions from two phase LV inclusions (Fig. 2b). The LVuid inclusions have first melting temperatures as low as −55 ◦Cnd final ice melting temperatures of −50 to ∼0 ◦C, indicatingCa-rich composition and wide range of salinities estimated as


5–30 wt% total dissolved solids.Carbonic fluid inclusions have melting points close to the

riple point of CO2 at −56.6 ◦C indicating a high purity. How-

Lso

elow the CO2 homogenisation temperature CO2 vapour is visible within CO2

ns as for Table 1.

ver, CO2 homogenisation into the liquid phase varies between20 and +30 ◦C indicating variable density (0.6–1.0 g cm−3).inor N2 or H2O (≤3 mol%) is present in some CO2 inclusions

Fu et al., 2003, 2004). The mixed aqueous-carbonic fluid inclu-ions have variable degrees of CO2-fill, but always decrepitateefore complete homogenization, making it difficult to estimatehe salinity of LLcD inclusions. The clathrate melting temper-ture of LLc fluid inclusions was −10 to +9 ◦C, indicatingalinities of 2–21 wt% NaCl eq. (calculated with FLINCOR;rown, 1989).

The regional alteration samples exhibit similar decrepitationehaviour to that reported for IOCG samples (Kendrick et al.,006b, 2007). However the exceptional abundance of CO2 fluidnclusions in samples from Knobby Quarry has allowed themo be studied in much greater detail (Table 1). In these and the


ime Creek samples, the mixed aqueous-carbonic fluid inclu-ions (LLcD and LLc) decrepitate at the lowest temperaturesf 180–250 ◦C and the pure CO2 fluid inclusions decrepitate at


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0gmis4 Ar/ Ar values, age-corrected for post-entrapment in situ pro-duction of radiogenic 40Ar since 1525 Ma, are only ∼1–6%lower than the measured values for most samples and most



nly very slightly higher temperature. Of the aqueous varieties,ost LV fluid inclusions decrepitate, in the approximate temper-

ture range 300–450 ◦C, before the higher salinity LVD plus MSuid inclusions which preferentially decrepitate at temperaturesreater than ∼400 ◦C (e.g. Fig. 2b). However, fluid inclusionecrepitation temperature is also dependent on shape and sizeBodnar et al., 1989; Kendrick et al., 2006b), and some of themallest fluid inclusions of all the varieties were undecrepitated,r have only partially leaked after heating to 600 ◦C.

. Methodology

.1. Sample preparation and irradiation

High purity mm-sized quartz grains (70–120 mg) wereleaned in an ultrasonic bath with distilled water and acetone,acked in Al-foil and irradiated in two batches for 150 MW h inosition 5c of the McMaster Nuclear Reactor, Canada (Irradia-ions designated UM#8 and UM#13). In both cases the neutronuence was monitored using the Hb3Gr (1072 Ma) and GA155098.8 Ma) flux monitors (Roddick, 1983; Renne et al., 1998;

cDougall and Harrison, 1999). J-values were determined fromoth monitors and the additional � and � parameters were deter-ined from Hb3Gr alone (Roddick, 1983; Kelley et al., 1986).he total neutron fluence (fast and thermal) was calculated as1019 neutrons cm−2 for both irradiations (Appendix).

.2. Mass spectrometry

Sample gas was extracted by stepped heating 69–97 mg ofach sample in a tantalum resistance furnace and four smallerample duplicates (22–47 mg) were analysed by in vacuo crush-ng in modified nupro® valves. During stepped heating eachample was cyclically heated in increments from an idle tem-erature of 100 ◦C up to a maximum of 1560 ◦C. Individualteps had a duration of 20 min and increased in 50–100 ◦C incre-ents from 200 ◦C to 700 ◦C, but in larger increments at higher

emperature (Kendrick et al., 2006b).Extracted gas was gettered by a cold GP50 st707 furnace

etter throughout the 20 min heating step and then for a further0 min using a combination of hot (300 ◦C) and cold SAES®

P10 st101 and/or SAES® GP50 st707 getters. The purifiedoble gases were subsequently expanded for isotopic analysisnto the MAP-215 noble gas mass spectrometer at the Universityf Melbourne. Argon isotopes were measured on the Faradayetector and the less abundant Kr and Xe isotopes were mea-ured at a relative gain of ∼400 using the more sensitive electronultiplier detector.

.3. Gas concentrations and analytical uncertainty

Chlorine, Br, I, K, Ca and U are determined from the neutronux and the measured abundance of nucleogenic (and fissio-


enic) noble gas isotopes: 38ArCl,80KrBr, 128XeI, 39ArK, 37ArCa

nd 134XeU (Johnson et al., 2000; Kendrick et al., 2006b).The Br/Cl and I/Cl values are proportional to the measured

0KrBr/38ArCl and 128XeI/38ArCl values (Kendrick et al., 2006b).

e

tepped heating (≤500 ◦C) samples from the Cloncurry District and the Maryathleen Fold Belt (MKFB; see Table 2).

nalytical uncertainty is highest in low gas volume extractionteps, with minimum values of 0.1% for Ar/Ar ratios, and 2–3%or Kr/Ar and Xe/Ar ratios. Total uncertainty reported at theσ level is determined by the relative fluxes of resonant andhermal neutrons which, based on multiple analyses of selectedamples and the Shallowater I-Xe standard included in severalrradiations, is estimated as 10% for Br/Cl and 15% for I/ClKendrick et al., 2006b).

Bulk sample concentrations of K and U are calculated fromhe total 39ArK and 134XeU released during stepped heating anal-sis, the irradiation parameters, the mass of the sample analysednd the mass-spectrometer sensitivity. The precision is ∼20%or K concentration but is only semi-quantitative for U concen-rations as a suitable monitor was unavailable.

. Noble gas and halogen data

.1. K-poor quartz

Fluid inclusion K/Cl values were determined by in vacuorushing and from low temperature stepped heating steps≤500 ◦C), which preferentially extract fluid inclusions, and areostly in the range 0.01–0.15 (Fig. 3 and Table 2). These values

re slightly lower than have been determined for K-rich IOCGuids analysed by this technique (Kendrick et al., 2006b, 2007).

The two maximum K/Cl values in samples 02CC47 and2CC62, determined at temperatures of >500 ◦C, are slightlyreater than one, indicating the presence of very minor K-ineral impurities in the quartz matrix or accidentally trapped

n the fluid inclusions (Kendrick et al., 2006c). However, theample K concentrations of 4–73 ppm are sufficiently low that0 36


xtraction steps1. Because the age-correction is so small, the

1 The largest corrections were ∼10–40% for samples 02CC52 and 02CC113.


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xxx–xxxTable 2Noble gas, halogen, K and U data summary for regional quartz veins associated with large-scale Na–Ca alterationSample Temperature

(◦C)

40Ar/36ArAge-correcteda

Cl/36Ar × 106 40ArE/Cl × 10−6 NaCl eq. wt% [36Ar] ppb [40ArE] ppm F84Kr F129Xe Range (200–700 ◦C)b K/Cl K U

Range Range Range Representativec Representativec Representativec Range Rangee Br/Cl × 10−3 I/Cl × 10−6 Range wt% (FI) ppm(FI + Matrix)

ppb(FI + Matrix)

Cloncurry District ∼1530–1520 Ma Na–Ca AlterationSnake Creek

02CC47 200–400 5,870–24,930 12–84 100–470 10–25 0.7–1.8 6.8–80 1.3–2.8 1.0–1.3 6.0–10 0.07–0.23 1–3.2 73 58>400 2,920–11,740 67–280 34–64 25–40 0.5–0.9 5.8–18 0.6–1.9 0.57–0.91 2.4–5.4 0.08–2.1 >1.8

02CC50 200–400 1,090–4,960 66–130 27–71 10–25 0.5–1.2 1.8–12 1.1–1.5 0.42–0.45 4.3–4.9 0.07–0.08 1.0–1.1 43 2>400 1,600–4,570 85–230 17–23 25–40 0.7–1.1 2.9–6.3 0.9–1.1 0.38–0.40 3.5–3.7 0.07–0.26 1.5–5.7

02CC52 200–400 350–460 6–51 4–10 10–25 1.2–3.0 0.3–1.7 1.1–2.2 0.80–1.1 1.6–2.2 0.06 0.8 26 3>400 550–2,010 100–200 3–16 25–40 0.8–1.2 0.5–4.4 1.3–1.9 0.57–0.88 1.1–2.2 0.04–0.17 0.9–3.7

Roxmere02CC113 200–400 290–2,370 7–94 3–4 10–25 0.7–1.6 0.2–0.7 1.1–1.9 0.56–0.82 1.4–4.0 0.06 0.8 34 6

>400 530–850 16–230 2–4 25–40 0.7–1.1 0.3–1.1 1.0 0.32–0.51 0.18–1.2 0.04–0.17 0.9–3.7

Cloncurry Fault02CC143 200–400 810–2,220 3–57 28–190 10–25 1.1–2.7 1.9–33 1.7–1.9 1.2–1.9 2.4–3.7 0.05 0.7 6 1

>400 880–2,900 47–130 13–20 25–40 1.2–1.9 2.2–5.5 0.7–2.1 0.53–0.88 1.6–2.2 0.05–0.09 1.1–2.0

Mary Kathleen Fold Belt ∼1555–1520 Ma Na–Ca AlterationTribulation

02CC05 200–400 540–650 2–27 11–13 10–25 2.3–5.7 0.8–2.2 0.6–1.3 1.1–2.3 1.5–3.3 5.0–17 0.03 0.4 5 72>400 290–800 8–36 8–24 25–40 4.3–6.8 1.4–6.6 0.6–1.3 2.8–3.1 5.8–16 0.04–0.08 0.9–1.8

02CC82 200–400 280–630 6–41 8 10–25 1.5–3.8 0.5–1.4 1.1–2.0 0.9–4.5 3.1–3.2 3.7–11 0.01–1.4 >0.1 14 8>400 330–2,720 20–79 2–31 25–40 1.9–3.1 0.3–8.5 0.5–1.3 2.5–2.6 6.6–10 0.01–0.13 0.2–2.9

02CC85 200–400 360–740 2–26 17–38 10–25 2.4–5.9 1.2–6.5 1.3–0.9 1.0–3.5 3.1–3.2 7.3–7.4 0–0.01 <0.1 19 5>400 540–1,200 24–48 12–23 25–40 3.2–5.1 2.1–6.3 0.7–1.3 2.8–3.3 4.9–7.7 0.03–0.34 0.7–7.5

Sunrise02CC62 200–400 1,260–2,990 5–24 110–180 10–25 2.6–6.4 7.5–31 1.5–1.8 3.4–4.0 19–22 0.02–0.04 0.3–0.5 4 7

>400 2,730–4,220 16–43 90–240 25–40 3.6–5.7 15–66 1.2–1.6 3.1–3.3 25–31 0.04–0.09 0.9–2.0

Knobby02CC108 200–400 1,480–3,920 4–14 170–290 10–25 4.4–11 12–50 0.8–1.2 1.0–3.5 1.2–1.4 14–20 0.14–0.15 1.9–2.1 31 20

>400 1,630–7,330 28–250 20–64 25–40 0.6–1.0 3–18 0.7–0.8 0.43–0.70 5.5–7.7 0.02–0.27 0.4–5.9

02CC38 200–400 1,720–6,260 1–21 280–980 10–25 2.9–7.3 19–170 1.0–1.2 1.2–1.3 10–13 0.16–0.28 2.2–6.2 24 2>400 3,720–6,150 23–64 57–190 25–40 2.4–3.8 9.7–52 0.8–1.7 0.74–1.3 6.1–11 0.13–0.40 2.9–8.8

Lime Creek02CC93 200–400 840–1,080 19–24 23–42 10–25 2.6–6.4 1.6–7.2 1.3–1.7 1.2–1.3 33–35 0.07 1.0 9 5

>400 490–940 13–31 19–30 25–40 5.0–7.9 3.2–8.2 1.3–1.5 0.88–1.3 29–33 0.03–0.38 0.4–5.2

02CC96 200–400 520–1,800 2–65 19–140 10–25 0.9–2.4 1.3–24 1.3–2.3 2.0–2.5 20–24 0.05–0.06 0.7–0.8 12 1>400 580–1,240 34–99 8–14 25–40 1.6–2.5 1.4–3.8 0.8–1.1 2.0–2.4 24–20 0.02–0.11 0.4–2.4

Reference valuesd

Meteoric-seawater 295.5 0–17 0 0–30 1.3–2.7 0 2.0–2.1 3.6–4.2 1.54* 0.86* 0.02*Mantle fluids ∼44,000 10–30 ∼1000 <8 <0.2 2–5 0.9–2.0 9.3–40

a Corrected for post-entrapment production of radiogenic 40Ar.b Temperature range considered most representative of fluid inclusion Br/Cl and I/Cl values (Kendrick et al., 2006a). Other parameters based on Ar isotopes only include high temperature data.c Representative Ar concentrations have been calculated from salinity ranges of 10–25 wt% for LV dominated fluid inclusions and 25–40 wt% NaCl eq. for LVD and MS dominated fluid inclusions (see text), but *lower salinities have been used for the Knooby Quarry samples in which

Cl-poor CO2 fluid inclusions dominate (Table 1, see text). Although all ratios are molar, Ar concentrations are given in ppb and ppm to enable comparison with Cl and K concentrations, conventionally given by mass. 1 ppb 36Ar ∼ 1.6 × 103 cm3 g−1 H2O; 1 ppm 40Ar ∼ 1.8 cm3 g−1

H2O.d Reference values in Zherebtsova and Volkova (1966), Burnard et al. (1997), Moriera et al (1998), Johnson et al. (2000) and Ozima and Podosek (2002). Asterisk refers to seawater values.e F129Xe determined by in vacuo crushing.


ARTICLE IN+ModelPRECAM-2902; No. of Pages 20

M.A. Kendrick et al. / Precambrian

Fq4

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The Tribulation Quarry samples contain negligible CO2fluid inclusions (Table 1) and LV fluid inclusions preferentiallydecrepitated at ≤400 ◦C in these samples have a maximum

ig. 4. Log–log 40Ar/36Ar vs. Cl/36Ar plot for fluid inclusions in regionaluartz samples. The reference 40ArE/Cl slopes have atmospheric intercepts with0Ar/36Ar = 296.

ata would not be significantly altered if some of the fluids wererapped at ∼1595 Ma, ∼1555 Ma, or anytime after 1525 Ma (fullata set in Appendix).

.2. Fluid inclusion 40Ar/36Ar variability

The fluid inclusion Cl/36Ar values vary between 106 and× 108 in a range fairly typical of crustal fluids (Kendrickt al., 2001, 2002b, 2005). When present, the highest salin-ty LVD and MS fluid inclusions with the highest Cl/36Ar andowest 40ArE/Cl values, are preferentially decrepitated at tem-eratures of >400 ◦C (Table 2). Lower Cl/36Ar and slightlyigher 40ArE/Cl values are obtained from LV and/or CO2 fluidnclusions that are preferentially decrepitated at low temperatureTable 2).

The Cl/36Ar versus 40Ar/36Ar diagram permits visualizationf the 40Ar/36Ar values obtained for different fluid inclusionypes (Fig. 4): A positive correlation is obtained if the highestalinity fluid inclusions also have the highest 40Ar/36Ar valuee.g. sample 02CC52). The Cl/36Ar value is not correlated withhe 40Ar/36Ar value if all the major fluid inclusion types (CO2,V, LVD and MS) have similar 40Ar/36Ar values, or if the sam-le is dominated by a single type of fluid inclusion (e.g. samples2CC108 and 02CC96). Finally, a negative correlation shouldesult, if the CO2 and LV fluid inclusions with the lowest Cl/36Aralues have the highest 40Ar/36Ar values. However, negativeorrelations are weakly developed in Cl/36Ar versus 40Ar/36Arpace (e.g. sample 02CC47; Fig. 4). This may indicate that, inddition to the fluid inclusion variability, some of the scatter inhe 40Ar/36Ar versus Cl/36Ar diagram is due to the presence of a

inor atmospheric-component (Turner and Bannon, 1992; Irwin


nd Reynolds, 1995). An atmospheric-component would movell data points in Fig. 4 variable distances towards air, obscur-ng negative correlations but reinforcing positive correlationsKendrick et al., 2007).

((


Just over half of the samples analysed (three of five sam-les from the Cloncurry District and five of eight samples fromhe Mary Kathleen Fold Belt) have maximum 40Ar/36Ar val-es of less than ∼2700 (Table 2). The Knobby Quarry samples,hich are dominated by CO2 fluid inclusions, gave the high-

st 40Ar/36Ar values (6000–7000) of any samples from theary Kathleen Fold Belt (Table 2 and Fig. 4). The maximum

0Ar/36Ar value of ∼25,000 was obtained from the 300 ◦Cxtraction step of sample 02CC47 from the Snake Creek Anti-line in the Cloncurry District. Lower 40Ar/36Ar values werebtained from this sample at >400 ◦C, suggesting it is the LV orinor CO2 fluid inclusions in this sample that have the highest

0Ar/36Ar value (Table 2; Fig. 4).

.3. Fluid inclusion Ar concentration

The 36Ar and 40ArE2 concentration of the most saline LVD

nd MS fluid inclusions are calculated from the maximuml/36Ar and minimum 40ArE/Cl values (determined at tempera-

ures of >400 ◦C), and representative salinities of 25–40 wt%aCl eq. (Table 2). The 36Ar and 40ArE concentrations of

ower salinity LV fluid inclusions are estimated from the max-mum Cl/36Ar and minimum 40ArE/Cl values determined inhe 200–400 ◦C temperature range, and salinities of 10–25 wt%aCl eq. (Table 2). The uncertainty in the estimated Ar concen-

ration is determined by the large range of salinity used in thealculation.

The LV fluid inclusions are estimated to have similar 36Aroncentrations as LVD and MS fluid inclusions in any given sam-le (Table 2). However, the fluid inclusions in samples from theary Kathleen Fold Belt, have 36Ar concentrations of 1–11 ppb,hich are consistently higher than those of 0.5–3 ppb, deter-ined for fluid inclusions in Cloncurry District samples (Fig. 5;able 2). The 36Ar concentration is unrelated to the 40Ar/36Aralue and although the lowest 36Ar concentrations are calculatedor fluid inclusions in samples with the lowest Br/Cl values, theseata are not strongly correlated (Fig. 5b). In contrast, the high-st 40ArE concentrations of >50–100 ppm are calculated for fluidnclusions with the highest 40Ar/36Ar values (Table 2).

.3.1. Carbonic fluid inclusionsThe 36Ar concentration cannot be directly calculated from

he Cl/36Ar ratio for CO2 fluid inclusions, because the CO2 fluidnclusions do not contain Cl. However, we can place some limitsn the 36Ar concentration of CO2 fluid inclusions by comparinghe ‘apparent’ 36Ar concentrations determined for the assem-lage of fluid inclusions that are decrepitated at 200–400 ◦C inifferent samples and the abundance of CO2 fluid inclusions in


2 40ArE = excess 40Ar; 40Ar not attributable to an atmospheric origin40ArA = 296 × 36Ar) or in situ production from radiogenic decay of 40K40ArR).




Fig. 5. The 36Ar concentration is plotted as a function of (a) maximum 40Ar/36Ar (log scale) determined by stepped heating in the intervals 200–400 ◦C and >400 ◦C(b) sample mean Br/Cl determined by stepped heating in the intervals 200–400 ◦C and 400–700 ◦C (Table 2). Compositional fields representative of sedimentaryf ion ofm enrye

3

it1ctisfltcct3

est3

T

4

rttacnRt

r(foFi

esin the quartz matrix rather than the fluid inclusions (Table 2).As a result F129Xe values obtained by stepped heating are notrepresentative of the fluid inclusion values and are not reported(Appendix).

ormation waters and estimated for metamorphic fluids obtained by devolatilisatagmatic field is based on the highest-40Ar/36Ar fluid measured in the Ernest H

t al., 2007).

6Ar concentration of ∼6 ppb (02CC05; Table 2). If LV fluidnclusions in the Knobby Quarry sample 02CC108 also con-ain 6 ppb 36Ar, the higher ‘apparent’ 36Ar concentration of1 ppb determined for fluid inclusions in this sample (Table 2),ould be explained by decrepitation of CO2 fluid inclusionshat contain 36Ar but not Cl. If four times as many CO2 fluidnclusions (∼0.6–1.0 g cm−3) are decrepitated as LV fluid inclu-ions (∼1.0–1.4 g cm−3; Table 1), it is implied that the CO2uid inclusions contain only ∼1–2 ppb 36Ar. Alternatively, if

he aqueous fluid inclusions in sample 02CC108 had a 36Aroncentration of only 1 ppb, similar to the ‘apparent’ 36Ar con-entration determined for this sample above 400 ◦C (Table 2),he CO2 fluid inclusions could contain as much as 3–4 ppb6Ar. Although it is difficult to assign an uncertainty to thesestimates, the similarity of ‘apparent’ 36Ar concentrations inamples with 0–80% CO2 fluid inclusions, strongly suggestshat the CO2 fluid inclusions are not (strongly) enriched in6Ar relative to the aqueous fluid inclusions (compare data fromables 1 and 2).

.4. Krypton, Xe and U

The fluid inclusion 129Xe/36Ar and 84Kr/36Ar values areeported as fractionation values (F84Kr and F129Xe) relative tohe atmospheric ratios in Table 2 and Fig. 6. The majority ofhese F-values are in the range expected for mixing a modernir contaminant and fluid inclusion Air Saturated Water (ASW),


onsistent with the presence of a minor atmospheric compo-ent (Fig. 5; Section 4.2; Turner and Bannon, 1992; Irwin andeynolds, 1995). However, some of the F84Kr values are less

han one, and the data could alternatively represent the non-

FbF0

the Corella Formation (see Kendrick et al., 2007) are shown for reference. TheIOCG and in the Cloncurry Na–Ca alteration (see also ovals in Fig 8; Kendrick

adiogenic noble gas elemental composition of mid-crustal fluidsKendrick et al., 2007). These data do not provide good evidenceor phase separation, which leads to highly fractionated F-valuesf �1 in the residual phase (Kendrick et al., 2001). Fractionated-values might have been expected if the water-dominated fluid

nclusions had exsolved CO2.Neutron-induced fissiogenic 134XeU (and 129XeU) was pref-

rentially extracted during stepped heating our irradiatedamples, indicating that U present at the ppb level is situated


ig. 6. (a) The noble gas fractionation values F129Xe and F84Kr determinedy in vacuo crushing four samples from the Mary Kathleen Fold Belt, see also84Kr in Table 2. FX = (X/36Ar)sample/(X/36Ar)air ASW = air saturated water atand 20 ◦C (Ozima and Podosek, 2002).




Fig. 7. Fluid inclusion Br/Cl vs. temperature (200–700 ◦C). The relative fluidinclusion abundances are given in Table 1, when present the LVD and MS fluidinclusions decrepitate at the highest temperatures. The data are displayed sepa-rately for samples from the (a) Mary Kathleen Fold Belt and (b) the CloncurryDrV

4

poTc(dtgpa

up

Fig. 8. Br/Cl vs. I/Cl (linear scales) for fluid inclusions in quartz veins relatedto (a) regional Na–Ca alteration and (b) the Ernest Henry and OsborneIOCG mineralisation (Fisher et al., 2005; Kendrick et al., 2006b, 2007).The most likely Br/Cl and I/Cl value of magmatic fluids in the Clon-curry District are identified by the ovals in both figures and are based onfluids with the highest 40Ar/36Ar values (Kendrick et al., 2007). In gen-eral 40Ar/36Ar decreases away from this field, the range of values areshown for each sample group where space permits (Table 2). The com-positional fields of evaporated seawater, halite and I-type magmatic fluidsbaa

ca0BQpb

4

istrict (see Fig. 1). The seawater Br/Cl value is shown for reference, with theange for I-type magmatic fluids shown as a shaded envelope (Zherebtsova andolkova, 1966; Johnson et al., 2000; Kendrick et al., 2001).

.5. Non-uniform halogen signatures

The Br/Cl values determined for fluid inclusions in each sam-le are either fairly constant or they decrease as the temperaturef the extraction step is increased from 200 to 700 ◦C (Fig. 7).he decrease in Br/Cl value is strongest for the samples thatontain a significant number of LVD and MS fluid inclusionsFig. 7; Table 1). As these fluid inclusions are preferentiallyecrepitated at high temperature it is suggested that they havehe lowest Br/Cl values. However, the inter-sample variation isreater than the intra-sample variation (Fig. 8) and so it is notossible to assign a range of Br/Cl values as characteristic of


ny one type of fluid inclusion.The highest Br/Cl values of 2–4 × 10−3 and I/Cl values of

p to 35 × 10−6 were obtained from fluid inclusions in sam-les from the Mary Kathleen Fold Belt (Fig. 5; Table 2). In

Nc

ased on Porphyry Copper ore deposit and mantle diamond fluid inclusionsre shown for reference (Zherebtsova and Volkova, 1966; Holser, 1979; Bohlkend Irwin, 1992; Johnson et al., 2000; Kendrick et al., 2001).

ontrast, fluid inclusions in samples from the Knobby Quarrynd the Cloncurry District have much lower Br/Cl values of.3–2 × 10−3 and I/Cl values of 0.2–10 × 10−6 (Fig. 8). Ther/Cl values determined for fluid inclusions in the Knobbyuarry samples overlap the range of 1.4–1.7 × 10−3 reportedreviously for two quartz samples from this location analysedy a different technique (Heinrich et al.,1993).

.6. Regional variation and comparison with IOCG


Fluid inclusions in quartz samples associated with regionala–Ca alteration in the Mary Kathleen Fold Belt and the Clon-

urry District are distinguished from each other by several


ARTICLE IN+ModelPRECAM-2902; No. of Pages 20

12 M.A. Kendrick et al. / Precambrian

Fig. 9. Fluid inclusion 40Ar/36Ar histograms for the regional Na–Ca alterationand IOCG samples (Fisher et al., 2005; Kendrick et al., 2006b, 2007). The valuesof sedimentary formation water and values estimated for metamorphic volatilesffl

ghl(ifiK(

tiK

5

lmaNgtl

5

ismuwieisIewflt

rbliTbaa((yffl(ii

5

MafflwssVss1s(Bia

Low-40Ar/36Ar aqueous fluids in the Cloncurry District

rom the Corella Formation and deeply derived magmatic (or metamorphic)uids are shown for reference (Kendrick et al., 2007).

eochemical parameters: (1) Fluid inclusions generally haveigher Br/Cl and I/Cl values in samples from the Mary Kath-een Fold Belt than in samples from the Cloncurry DistrictFig. 8). (2) Fluid inclusions have higher 36Ar concentrationsn samples from the Mary Kathleen Fold Belt than in samplesrom the Cloncurry District (Fig. 5). (3) The maximum fluidnclusion 40Ar/36Ar value is lower in samples from the Maryathleen Foldbelt than in samples from the Cloncurry District

Fig. 9).Fluids associated with Na–Ca alteration in the Cloncurry Dis-

rict are similar to fluids associated with IOCG mineralizationn the Cloncurry District (Figs. 8 and 9; Fisher et al., 2005;endrick et al., 2006b, 2007).

. Discussion

The highly variable results obtained from the Mary Kath-een Fold Belt and Cloncurry District samples suggest thatultiple fluid sources and processes control the noble gas

nd halogen composition of fluid inclusions associated witha–Ca alteration (Fig. 1). In the discussion that follows we


roup fluid types that may have had similar origins based onheir 40Ar/36Ar value and XCO2, rather than their geographicocation.

avi


.1. Dominant, low-40Ar/36Ar aqueous fluids

The 40Ar/36Ar values of less than ∼2700 that character-ze aqueous (LV, LVD, MS) fluid inclusions in the majority ofamples (Tables 1 and 2), do not favour a deep magmatic or meta-orphic fluid source. Furthermore, the low 40Ar/36Ar values are

nlikely to be explained by interaction of a deeply derived fluidith upper or mid-crustal rocks because the 36Ar concentration

s not correlated with the 40Ar/36Ar value (Fig. 5; cf. Kendrickt al., 2006a). In addition, there is no evidence of Ar-loss dur-ng phase separation (Fig. 6) which could lead to the noble gasignature being more easily overprinted (Kendrick et al., 2007).nstead, the moderately high 40Ar/36Ar values, are more easilyxplained if the fluid originated as either sedimentary formationater in the upper crust, or as a metamorphic devolatilisationuid sourced from 36Ar-rich meta-sedimentary rocks close to

he mid-crustal level of alteration (Kendrick et al., 2007).A predominant origin from sedimentary formation waters

ather than as a locally derived metamorphic fluid is favouredy several factors. (1) The variable Br/Cl and I/Cl values ofow-40Ar/36Ar aqueous fluids indicates different fluid sourcesn the Mary Kathleen Fold Belt and the Cloncurry District.he variability does not support a single magmatic or rockuffered metamorphic origin for these ligands (cf. Marshallnd Oliver, 2006). (2) Published stable isotope data precludefluid derived exclusively by devolatilisation of the host rocks

Oliver et al., 1993; Mark et al., 2004; Marshall et al., 2006).3) Devolatilisation of the calcite-rich Corella Formation wouldield a fluid with XCO2 of 0.3–0.75 (Oliver et al., 1992),avouring an even higher than observed abundance of CO2uid inclusions in quartz veins hosted by calc-silicate rockscf. Table 1). (4) Similarities in the alteration style and fluidnclusion assemblages (Table 1) of diverse protoliths alsondicate external fluid buffering (de Jong and Williams, 1995).

.1.1. Diverse sources of salinityLow-40Ar/36Ar aqueous fluid inclusions in samples from the

ary Kathleen Fold Belt have high Br/Cl and I/Cl values, thatre similar to those characteristic of bittern brine sedimentaryormation waters (Hanor, 1994; Kendrick et al., 2002a,b). Suchuids acquire high I/Cl values by sub-surface fluid interactionith organic-rich sedimentary rocks, whereas their higher than

eawater Br/Cl values result from the sub-aerial evaporation ofeawater beyond the point of halite saturation (Zherebtsova andolkova, 1966; Hanor, 1994; Worden, 1996). As a result, thealinity of bittern brines (evaporated seawater) cannot exceed thealinity of halite-saturated seawater (Zherebtsova and Volkova,966; Hanor, 1994). The Dead Sea brine is an example ofuch a fluid with a salinity of ∼31 wt% total dissolved solidsNissenbaum, 1977). Fluid inclusions in the Mary Kathleen Foldelt include halite-saturated LVD and MS varieties (Table 1),

ndicating that if these fluids originated as bittern brines, somedditional process has enhanced their salinity.


re dominated by lower than seawater Br/Cl values and I/Clalues that are significantly lower than those of fluid inclusionsn samples from the Mary Kathleen Foldbelt (Fig. 8). The


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owest Br/Cl value of 0.3 × 10−3, and the lowest I/Cl value of.2 × 10−6, obtained for LVD and MS fluid inclusions in sample2CC113 (Table 2), are similar to sedimentary formation watershat have dissolved halite (Fig. 8; Holser, 1979; Hermann,980; Bohlke and Irwin, 1992). Provided halite dissolutionccurs in the sub-surface, at greater than atmospheric pressurend temperature, the resultant brine salinity could far exceedhat of halite-saturated seawater.

Therefore, the total range in Br/Cl and I/Cl values (Fig. 8),nd the ultra-high salinity of some low-40Ar/36Ar aqueousuid inclusions, can be explained if bittern brine sedimentaryormation waters dissolved variable amounts of halite. Theistinct Br/Cl and I/Cl values determined for Na–Ca alterationuids in the Mary Kathleen Fold Belt compared to the Clon-urry District probably indicates that the original bittern brinesn each of these districts had distinct compositions prior toissolving halite. Therefore, the data suggest broadly similarut independent origins for Na–Ca alteration fluids in the Maryathleen Fold Belt, and the Cloncurry District.

.1.2. ScapoliteOne difficulty with invoking halite dissolution as an important

ource of salinity for post-peak (∼1520–1530 Ma) metamorphiclteration fluids in the Eastern Fold Belt is that halite-rich evapor-tes originally present in the Corella Formation were transformednto scapolite during the ∼1575–1595 Ma metamorphic peakFoster and Rubenach, 2006). However, if meta-evaporiticcapolite preserves the low Br/Cl and I/Cl values of halitePan and Dong, 2003), the dissolution (or devolatilisation) ofetamorphic-scapolite could have the same effect as the disso-

ution of halite. Scapolite dissolution is a viable source for Cl-ominated ligands in Na–Ca alteration fluids because the alter-tion overprints the regional metamorphic fabric and replacescapolite (Oliver, 1995; Foster and Rubenach, 2006; Marshallnd Oliver, 2006). However, an alternative explanation is thatalite dissolution took place in younger sediments that couldave been present above the present erosion level and may haveetained halite after peak metamorphism (Kendrick et al., 2007).

.2. Snake Creek high-40Ar/36Ar fluids

The maximum measured fluid inclusion 40Ar/36Ar value of25,000 in sample 02CC47 from Snake Creek (Table 2) is

onsistent with the involvement of a deeply derived fluid, ofither metamorphic or magmatic origin. Aqueous fluid inclu-ions with 40Ar/36Ar values intermediate between 25,000 and2700 (Tables 1 and 2) probably represent dilute mixtures of

his deeply derived fluid and the dominant low-40Ar/36Ar sedi-entary formation water (Fig. 9).Fluid inclusions in sample 02CC47 could have been trapped

ny time after peak metamorphism (Section 2.3), suggesting thatrapping of metamorphic fluids during an early phase of Na–Ca


lteration is possible. However, fluids with high 40Ar/36Ar val-es interpreted to have had a metamorphic basement-originn the Mt Isa Cu deposit, are distinguished by much higherr/Cl and I/Cl values than fluid inclusions in sample 02CC47

Cor2


Kendrick et al., 2006a). In addition, high-40Ar/36Ar fluidsre not involved in syn-metamorphic IOCG mineralization atsborne (Fig. 9; Fisher et al., 2005), suggesting that they areot a common feature of peak metamorphism in the district.

In contrast, the high-40Ar/36Ar fluid inclusions in sample2CC47 are very similar to fluids that were involved inost-peak-metamorphic IOCG mineralization at Ernest Henry,hich were interpreted to have had a magmatic origin (seeigs. 8 and 9; Kendrick et al., 2007). A similar magmatic origin

s possible in this case because, the area surrounding the Snakereek Anticline was overprinted by late-Isan Na–Ca Alterationt ∼1530 Ma, broadly coincidental with intrusion of the nearbyaxby Granite and major phases of the Williams-Narakuatholiths elsewhere (Fig. 1; Page and Sun, 1998; Mark et al.,006b; Rubenach et al., this issue). Magmatic fluids sourcedrom ‘A-type’ granites generated by melting Palaeoproterozoicgneous rocks in the basement would probably have mantle-liker/Cl and I/Cl values similar to those measured (Kendrick etl., 2007).

A small difference between the high-40Ar/36Ar fluid inclu-ions analysed in sample 02CC47 and the Ernest Henry samples their temperatures of decrepitation (Table 2; Kendrick et al.,007). The highest 40Ar/36Ar value was determined at 300 ◦Cor sample 02CC47 implying a dominant source from low salin-ty LV (or CO2) fluid inclusions (Fig. 4; Section 4.2). In addition,he high-40Ar/36Ar fluid inclusions in sample 02CC47 are esti-

ated to have a 36Ar concentration of <2 ppb, compared to–6 ppb for the more saline magmatic fluid inclusions in thernest Henry sample (Table 2; Kendrick et al., 2007). If both

hese fluids had a magmatic origin, the differences in salinityand 36Ar concentration) could be explained by the degree tohich the pluton they were exsolved from had crystallized (seeline and Bodnar, 1991). The bulk salinity of magmatic fluidsxsolved from plutons in the mid-crust can vary from 2 to 84 wt%aCl eq. depending on the P-T-XNaCl conditions at which firstr second boiling takes place (Cline and Bodnar, 1991).

.3. CO2 fluid inclusions

The noble gas composition of CO2 fluid inclusions is bestonstrained by the Knobby Quarry samples where they have anbundance of ∼80% (Table 1). These samples have a maximum0Ar/36Ar value of 6000–7000 (Table 2; Fig. 4), which is signif-cantly higher than determined for the dominant aqueous fluidnclusions in most other samples (Section 5.1; Fig. 9). This dif-erence precludes a CO2 origin in these samples by unmixingrom the regionally dominant aqueous fluid.

The 40Ar/36Ar value of 6000–7000 is significantly lower thanhe MORB mantle value of 44,000 (Burnard et al., 1997; Morierat al., 1998) and the value of ∼25,000–29,000 determined formagmatic’ fluids associated with late-Isan Na–Ca alteration andOCG mineralization in the Cloncurry District (Fig. 9; Kendrickt al., 2007). This indicates that a significant proportion of the


O2 had a non-magmatic crustal origin. The most likely sourcef crustal CO2 is devolatilisation of the calcite-rich calc-silicateocks that host the most intense alteration (Oliver et al., 1993,004; Oliver, 1995; Rubenach and Lewthwaite, 2002; Mark et


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l., 2004). CO2 fluid inclusions with a minor N2 component,uch as those reported in similar samples related to Na–Ca alter-tion in the Eastern Fold Belt (Fu et al., 2003, 2004), are commonn high-grade metamorphic fluids and commonly have a sourcerom meta-sedimentary units (e.g. Andersen et al., 1993).

Nonetheless, it is not possible to completely exclude a minorantle or magmatic CO2 component, because the 40Ar/36Ar

alue of a CO2-rich fluid sourced by devolatilisation of the calc-ilicate Corella Formation is poorly constrained (Kendrick et al.,007). Depending on the 36Ar concentration in the sedimentaryrotolith, and the extent of Ar-loss during peak metamorphism,he 40Ar/36Ar value of a metamorphic fluid sourced by devolatil-sation of the calc-silicate Corella Formation could vary from

1000 to >7000 (Kendrick et al., 2007). In addition, the Br/Clnd I/Cl values of the aqueous fluid inclusions in the Knobbyuarry samples are similar to those of the mantle (Fig. 8), com-atible with but not diagnostic of a magmatic component.

.3.1. Aqueous-carbonic fluid inclusionsCO2 fluid inclusions are much less abundant in samples

ollected from outside the Knobby Quarry (Table 1), and their0Ar/36Ar compositions must be inferred. The Lime Creek andloncurry Fault samples yield 40Ar/36Ar values of ∼1000–3000

rom both moderately abundant LLc plus CO2 fluid inclusionshat are preferentially decrepitated at 200–400 ◦C, and higheralinity LVD and MS fluid inclusions that are preferentiallyecrepitated at >400 ◦C (Table 2; Fig. 4; Sections 2.3 and 4.2).O2 fluid inclusions are only a minor component of the Snakereek samples (Table 1) but could be partly responsible for theighest 40Ar/36Ar value of ∼25,000 that was measured in a lowemperature extraction step from sample 02CC47 (Section 4.2;able 2).

It is difficult to interpret the variable isotopic compositionsf these less abundant CO2 fluid inclusions (Table 1). Theseata could indicate that, like the H2O-rich fluids, there wereultiple sources of CO2 during Na–Ca alteration. However,

t is also possible that the isotopic composition of a relativelymall CO2 component reflects the isotopic composition of theuid from which the CO2 most recently mixed, rather than theltimate source of CO2.

.4. CO2–H2O mixing versus unmixing

Minor fluid unmixing could follow CO2–H2O mixing. How-ver, a dominant role for fluid mixing is suggested by thenterpretation that sedimentary formation waters are the mainource of low-40Ar/36Ar aqueous fluids (Section 5.1). Such flu-ds are not a good source of CO2, implying that CO2 must haveeen introduced independently. An independent source for CO2s further supported by the following arguments: (1) The Ar-sotope composition of CO2 fluid inclusions, best preserved inhe Knobby Quarry samples, is different to that of the domi-ant aqueous fluids (Section 5.3). (2) Noble gas elemental ratios


re unfractionated and the concentration of 36Ar is similar inO2 and aqueous fluid inclusions (Section 4.4; Figs. 5 and 6).lternatively, if phase separation has occurred, this would

equire that the heavy noble gases are not strongly fractionated

−dfh


etween supercritical H2O and CO2 under mid-crustal condi-ions. Finally, (3) unmixing could not have occurred near to theite of entrapment because the high salinity aqueous fluid inclu-ions homogenize by halite dissolution (Fu et al., 2003, 2004).onetheless, unmixing could have occurred distally.

. Summary

The combination of noble gas plus halogen data and the exist-ng stable isotope constraints have lead us to several importantnterpretations that differ to those based solely on stable isotopeata (cf. Oliver et al., 1993; Mark et al., 2004; Marshall et al.,006). Stable isotope data have previously been used to suggestregionally homogenous externally derived fluid (Oliver et al.,993; Mark et al., 2004; Marshall et al., 2006). Our data areompatible with the interpretation of an external fluid source,ut indicate a high degree of fluid heterogeneity and demon-trate that alteration fluids in the Mary Kathleen Fold Belt hadroadly similar, but independent origins to alteration fluids inhe Cloncurry District (Fig. 10).

The greater variability displayed by fluid inclusion noble gasnd halogen data relative to stable isotope mineral data maye partly attributed to preservation of multiple pulses of fluidow in fluid inclusion trails that are time integrated (averaged)

n the isotopic composition of minerals. However, it is alsootable that the fluid inclusion noble gas and halogen compo-itions described above, vary by orders of magnitude betweenittern brine/halite dissolution sedimentary formation waters,etamorphic and magmatic fluids, whereas the stable isotope

omposition of all these fluid types can overlap (e.g. Ohmotond Goldhaber, 1997; Taylor, 1997).

Therefore the data presented here, together with the stablesotope data, demonstrate that the dominant fluid origin foruartz hosted aqueous fluid inclusions associated with Na–Calteration throughout the Eastern Fold Belt was sedimentaryormation waters, with halite/scapolite dissolution an impor-ant source of salinity. Magmatic fluids were probably involvedn late-Isan Na–Ca alteration in the Cloncurry District and its suggested that these fluids had a very similar range of ori-ins as fluids involved in IOCG mineralization at Ernest HenryFig. 1; Kendrick et al., 2007). These data are compatible withistrict scale convection of sedimentary formation waters driveny heat from the late-Isan Williams-Naraku Batholiths whichontributed minor magmatic fluids (Fig. 10).

Minor magmatic fluids, including CO2, may also have beenresent in the Mary Kathleen Fold Belt. However, the 40Ar/36Aromposition of CO2 fluid inclusions in the Knobby Quarry sam-les preclude a pure mantle or magmatic source and late-IsanA-type’ granites do not outcrop in this area (Fig. 1). Instead,

etamorphic devolatilisation of the host Corella Formation wasrobably one of the most important sources of CO2. We notehat the Corella Formation (�13C of −1.5 to +2‰) could alsoave been the main source of C in calcite veins (�13C of −0.6 to


7‰), if organic C with a much lower �13C (i.e. −35‰) wasissolved in the regionally dominant low-40Ar/36Ar sedimentaryormation water (Oliver et al., 1993; Marshall et al., 2006). Theighest I/Cl values are significantly above the Seawater Evapora-




F t al.,M lock.K KLBM

twaWpc(

A

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A

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ig. 10. Schematic diagram based on the Mt Isa seismic tansect (MacCready eary Kathleen Fold Belt and the Cloncurry Districts of the Eastern Mt Isa Bendrick et al., 2002a, 2002b). Abbreviations: MKFB, Mary Kathleen Foldbelt;ORB, Mid-Ocean Ridge Basalt.

ion Trajectory (Fig. 8) indicating that the sedimentary formationaters responsible for Na–Ca alteration had previously inter-

cted with I-rich organic-rich sedimentary rocks (Section 5.1.1;orden, 1996). A local origin for CO2, and carbonate, is com-

atible with the most intense Na–Ca alteration and the largestalcite pods being found in the calcite-rich Corella FormationOliver et al., 1993; Oliver, 1995; Mark et al., 2004).

cknowledgements

This research was funded by the Predictive Mineral Discov-ry Cooperative Research Centre (pmd*CRC) fluid history (H6)roject in collaboration with the fluids and Mt Isa projects (I7nd F3), and is published with permission. Stanislav Szczepan-ki is thanked for technical assistance in the noble gas laboratorynd Nick Oliver is thanked for assistance with sample collectionBF). Geordie Mark is thanked for access to the fluid inclusiontage at Monash University (MK). Although any faults remain


ur own, MK has benefited from discussions with Mike Rube-ach, Damien Foster and Geordie Mark. The manuscripts clarityas further improved by constructive reviews from Ray Burgess

nd Andrew Tompkins.

S

1998) and showing the independent late-Isan Na–Ca alteration systems in theReferences include (Burnard et al., 1997; Page and Sun, 1998; Mark, 2001;, Kalkadoon-Leichardt Belt; ASW, Air Saturated Water (seawater or meteoric);

ppendix A

.1. Irradiation parameters

arameter Irradiation

UM#8 UM#13

ate 7th November 2004 20th January 2006(mean) 0.0185 ± 0.0002 0.0161 ± 0.0002(mean) 0.55 ± 0.01 0.47 ± 0.02(mean) 4.8 ± 0.3 5.14 ± 0.07

hermal neutron flux (øt) 9.7 × 1018 ± 0.6 × 1018 8.8 × 1018 ± 0.2 × 1018

ast neutron flux (øt) 3.51 × 1018 ± 0.04 × 1018 3.06 × 1018 ± 0.04 × 1018

esonance correction (R) 1.60 1.20

esonance correction (R)r

1.25 1.05

nterference correctionsK-salt 40Ar/39Ar 0.030 ± 0.002 0.030 ± 0.002K-salt 38Ar/39Ar 0.0124 ± 0.0001 0.0124 ± 0.0001Ca-salt 39Ar/37Ar 0.00069 ± 0.00001 0.00069 ± 0.00001

36 37


Ca-salt Ar/ Ar 0.00032 ± 0.00001 0.00032 ± 0.00001

amples irradiatedCloncurry O2CC47, 02CC113 02CC52, 02CC50, 02CC143MKFB 02CC62, 02CC108, 02CC82,

02CC05, 02CC8502CC93, 02CC96, 02CC38


+ModelP

1

A

C

S

S

S

R

C

T

ARTICLE IN PRESSRECAM-2902; No. of Pages 20


.2. Noble gas and halogen stepped heating data

loncurry District

40Ar mols(10−15)

40Arcorr mols(10−15)

36Ar mols(10−15)

84Kr mols(10−18)

129Xe mols(10−18)

Cl mols(10−9)

K mols(10−9)

Br/Cl (10−3) I/Cl (10−6) U mols(10−15)

nake Creek 02CC47, 75 mg200 438 ± 1 434 ± 2 0.07 ± 0.01 4.1 ± 0.2 1.73 ± 0.06 0.9 ± 0.1 0.2 ± 0.1 1.3 ± 0.1 10 ± 1 121 ± 24300 15136 ± 13 15067 ± 44 0.60 ± 0.02 22.6 ± 0.9 11.2 ± 0.3 32 ± 2 4.1 ± 0.1 1.3 ± 0.1 7.9 ± 0.8 1469 ± 103350 5368 ± 3 5325 ± 13 0.40 ± 0.01 10.1 ± 0.5 3.54 ± 0.09 27 ± 2 2.62 ± 0.03 1.1 ± 0.1 6.2 ± 0.6 205 ± 18400 3817 ± 2 3776 ± 9 0.42 ± 0.01 9.8 ± 0.5 1.85 ± 0.04 36 ± 2 2.46 ± 0.05 1.0 ± 0.1 6.0 ± 0.6 58 ± 32500 5365 ± 4 5255 ± 14 0.55 ± 0.01 12.7 ± 0.5 1.28 ± 0.06 80 ± 5 6.6 ± 0.1 0.9 ± 0.1 5.4 ± 0.6 233 ± 23550 2296 ± 1 2215 ± 5 0.21 ± 0.02 3.7 ± 0.2 0.70 ± 0.07 34 ± 2 4.8 ± 0.1 0.80 ± 0.08 5.9 ± 0.6 84 ± 11600 357.5 ± 0.5 299 ± 2 0.030 ± 0.004 1.1 ± 0.2 4.8 ± 0.3 3.5 ± 0.1 0.57 ± 0.06 2.4 ± 0.6700 375.4 ± 0.3 253 ± 2 0.087 ± 0.005 1.1 ± 0.1 0.57 ± 0.02 5.8 ± 0.4 7.3 ± 0.1 0.58 ± 0.06 5.0 ± 0.5 11 ± 111100 1410 ± 2 560 ± 8 0.16 ± 0.04 3.9 ± 0.2 0.22 ± 0.02 24 ± 2 50.9 ± 0.3 0.72 ± 0.08 6.6 ± 0.7 1329 ± 931400 12712 ± 12 11878 ± 39 1.01 ± 0.01 22 ± 1 0.8 ± 0.1 285 ± 18 49.9 ± 0.1 0.73 ± 0.08 5.2 ± 0.5 5192 ± 3621600 3005 ± 3 2896 ± 9 0.33 ± 0.01 9 ± 1 0.58 ± 0.01 65 ± 4 6.5 ± 0.1 0.73 ± 0.08 5.7 ± 0.6 9486 ± 665

Total 50280 ± 19 47960 ± 64 3.87 ± 0.05 100 ± 2 22.5 ± 0.3 595 ± 20 138.8 ± 0.3 18189 ± 772

nake Creek 02CC50, 83 mg200 498.4 ± 0.4 498.4 ± 0.4 0.46 ± 0.01 13.9 ± 0.2 5.2 ± 0.2300 8315 ± 6 8172 ± 22 1.65 ± 0.02 42.6 ± 0.7 11.9 ± 0.4 109 ± 2 8.6 ± 0.1 0.45 ± 0.05 5 ± 1400 5032 ± 4 4839 ± 14 1.33 ± 0.01 29.7 ± 0.5 4.7 ± 0.2 170 ± 3 11.5 ± 0.2 0.42 ± 0.04 4.3 ± 0.5500 2389 ± 1 2279 ± 6 0.69 ± 0.01 12.7 ± 0.2 0.92 ± 0.06 96 ± 2 6.6 ± 0.1 0.40 ± 0.04 3.5 ± 0.4600 1511 ± 1 1430 ± 4 0.32 ± 0.01 7.6 ± 0.3 0.63 ± 0.02 60 ± 1 4.9 ± 0.1 0.38 ± 0.04 3.7 ± 0.4700 225.4 ± 0.4 225.4 ± 0.4 0.08 ± 0.01 1.7 ± 0.0 0.19 ± 0.01 7.2 ± 0.41100 483 ± 1 393 ± 2 0.25 ± 0.01 3.7 ± 0.1 0.41 ± 0.02 20.9 ± 0.4 5.4 ± 0.1 0.37 ± 0.04 3.5 ± 0.4 255 ± 191400 8798 ± 7 8134 ± 26 1.85 ± 0.01 36 ± 1 1.54 ± 0.05 432 ± 8 39.7 ± 0.5 0.33 ± 0.03 3.2 ± 0.3 272 ± 151540 3440 ± 2 3197 ± 9 0.73 ± 0.01 10.4 ± 0.4 0.63 ± 0.04 144 ± 3 14.6 ± 0.2 0.23 ± 0.02 1.8 ± 0.2 155 ± 16

Total 30692 ± 10 29167 ± 39 7.35 ± 0.03 158 ± 2 26 ± 1 1032 ± 10 91 ± 1 690 ± 29

nake Creek 02CC52, 89 mg200 70.7 ± 0.1 70.7 ± 0.1 0.201 ± 0.005 8.7 ± 0.1 4.6 ± 0.2 1.18 ± 0.02 1.1 ± 0.1 2.2 ± 0.4300 305.6 ± 0.3 280.2 ± 1.0 0.65 ± 0.01 16.7 ± 0.3 5.7 ± 0.2 25.8 ± 0.5 1.52 ± 0.02 0.93 ± 0.09 1.3 ± 0.1400 1445 ± 1 1292 ± 5 2.80 ± 0.02 59.2 ± 0.9 4.4 ± 0.2 144 ± 3 9.1 ± 0.1 0.80 ± 0.08 1.6 ± 0.2500 1442 ± 1 1398 ± 4 0.696 ± 0.004 23.6 ± 0.3 1.8 ± 0.1 75 ± 1 2.65 ± 0.04 0.88 ± 0.09 2.2 ± 0.2600 142.6 ± 0.2 101.7 ± 0.8 0.157 ± 0.003 4.2 ± 0.1 0.36 ± 0.02 25.7 ± 0.5 2.45 ± 0.07 0.57 ± 0.06 1.1 ± 0.1700 23.08 ± 0.02 15.5 ± 0.2 0.014 ± 0.009 0.52 ± 0.04 0.11 ± 0.02 2.7 ± 0.1 0.45 ± 0.02 0.65 ± 0.07 10 ± 51100 60.1 ± 0.1 40.9 ± 0.4 0.075 ± 0.002 2.31 ± 0.04 0.26 ± 0.02 7.7 ± 0.1 1.15 ± 0.02 0.69 ± 0.07 2.6 ± 0.3 271 ± 151400 1818 ± 2 1251 ± 9 1.78 ± 0.02 37.5 ± 0.7 2.1 ± 0.1 306 ± 6 33.9 ± 0.5 0.61 ± 0.06 1.6 ± 0.2 614 ± 291540 375.4 ± 0.2 257 ± 2 0.312 ± 0.004 5.4 ± 0.1 0.45 ± 0.02 54 ± 1 7.1 ± 0.1 0.50 ± 0.05 2.6 ± 0.3 110 ± 7

Total 5683 ± 3 4707 ± 11 6.69 ± 0.03 158 ± 1 19.8 ± 0.4 642 ± 7 58 ± 1 1004 ± 34

oxmere 02CC113, 71 mg200 43.0 ± 0.5 43.0 ± 0.5 0.15 ± 0.03 5.8 ± 0.2 2.4 ± 0.1 1.1 ± 0.1 0.82 ± 0.09 4.0 ± 0.8300 621.1 ± 0.5 564 ± 2 1.08 ± 0.01 38 ± 2 19.2 ± 0.5 67 ± 4 3.4 ± 0.1 0.70 ± 0.07 1.4 ± 0.2 24 ± 97400 825 ± 1 725 ± 3 1.31 ± 0.01 29 ± 1 8.3 ± 0.2 123 ± 8 6.0 ± 0.1 0.56 ± 0.06 1.4 ± 0.1500 740.4 ± 0.6 631 ± 3 0.87 ± 0.01 17.3 ± 0.7 1.85 ± 0.05 141 ± 9 6.5 ± 0.1 0.51 ± 0.05 1.2 ± 0.1 29 ± 11600 302.1 ± 0.1 245.0 ± 0.6 0.32 ± 0.01 6.1 ± 0.3 0.63 ± 0.02 68 ± 4 3.41 ± 0.02 0.44 ± 0.05 1.1 ± 0.1700 37.85 ± 0.01 37.85 ± 0.01 0.49 ± 0.06 1.2 ± 0.1 0.15 ± 0.03 8 ± 1 0.32 ± 0.03 0.18 ± 0.021100 210.8 ± 0.3 159 ± 1 0.30 ± 0.02 4.9 ± 0.2 0.40 ± 0.09 43 ± 3 3.1 ± 0.1 0.45 ± 0.05 1.1 ± 0.1 542 ± 401400 2521 ± 3 1934 ± 9 2.13 ± 0.02 35 ± 1 1.65 ± 0.05 489 ± 32 35.1 ± 0.1 0.42 ± 0.05 1.3 ± 0.1 1159 ± 811600 367.8 ± 0.5 290 ± 2 0.34 ± 0.01 4.9 ± 0.2 0.91 ± 0.02 54 ± 3 4.7 ± 0.1 0.41 ± 0.04 1.4 ± 0.1 103 ± 61

Total 5668 ± 3 4629 ± 11 7.0 ± 0.1 143 ± 3 35 ± 1 994 ± 35 62.2 ± 0.3 1858 ± 147

loncurry Fault 02CC143, 80 mg200 274.0 ± 0.4 274.0 ± 0.4 0.34 ± 0.01 12.7 ± 0.2 6.5 ± 0.2 0.9 ± 0.0 1.9 ± 0.2 3.7 ± 0.4300 2401 ± 3 2383 ± 8 1.07 ± 0.01 36.6 ± 0.7 7.7 ± 0.3 33.3 ± 0.6 1.13 ± 0.05 1.8 ± 0.2 2.7 ± 0.3400 2501 ± 2 2461 ± 7 1.30 ± 0.01 43.3 ± 0.7 3.9 ± 0.1 74 ± 1 2.41 ± 0.05 1.2 ± 0.1 2.4 ± 0.3500 1442 ± 1 1398 ± 4 0.696 ± 0.004 23.6 ± 0.3 1.8 ± 0.1 75 ± 1 2.65 ± 0.04 0.88 ± 0.09 2.2 ± 0.2600 419.6 ± 0.6 391 ± 2 0.444 ± 0.003 6.3 ± 0.1 0.56 ± 0.03 20.8 ± 0.4 1.69 ± 0.03 0.67 ± 0.07 2.0 ± 0.2700 132.9 ± 0.2 132.9 ± 0.2 0.05 ± 0.03 2.0 ± 0.1 0.23 ± 0.01 6.0 ± 0.1 0.53 ± 0.05 1.6 ± 0.2 25 ± 41100 949 ± 1 903 ± 3 0.52 ± 0.01 14.6 ± 0.3 0.73 ± 0.03 47.2 ± 0.9 2.78 ± 0.05 0.86 ± 0.09 1.9 ± 0.2 113 ± 71400 313.2 ± 0.4 300 ± 1 0.16 ± 0.02 2.8 ± 0.1 0.15 ± 0.01 16.7 ± 0.3 0.79 ± 0.03 0.57 ± 0.06 1.8 ± 0.2 39 ± 21540 640.9 ± 0.8 615 ± 2 0.40 ± 0.01 9.2 ± 0.2 0.43 ± 0.02 26.7 ± 0.5 1.55 ± 0.02 1.0 ± 0.1 3.9 ± 0.4 85 ± 5

Total 9074 ± 4 8857 ± 12 4.98 ± 0.04 151 ± 1 22.0 ± 0.4 301 ± 2 13.0 ± 0.1 262 ± 10

Please cite this article in press as: Kendrick, M.A., et al., Noble gas and halogen constraints on regionally extensive mid-crustal Na–Cametasomatism, the Proterozoic Eastern Mount Isa Block, Australia, Precambrian Res. (2007), doi:10.1016/j.precamres.2007.08.015

ribulation Quarry 02CC05, 75 mg200 61 ± 1 45 ± 1 0.45 ± 0.01 5.5 ± 0.3 2.2 ± 0.2 0.7 ± 0.0 1.0 ± 0.1 1.5 ± 0.2 5 ± 1 25 ± 32300 849.7 ± 0.6 835 ± 2 1.55 ± 0.02 46 ± 2 15.6 ± 0.5 35 ± 2 0.9 ± 0.1 3.3 ± 0.4 12 ± 1 117 ± 48350 981.2 ± 0.8 966 ± 3 1.60 ± 0.02 39 ± 2 5.7 ± 0.2 41 ± 3 0.92 ± 0.03 3.1 ± 0.3 14 ± 1 166 ± 25400 686.1 ± 0.4 680 ± 2 1.04 ± 0.01 27 ± 1 3.0 ± 0.1 28 ± 2 0.37 ± 0.03 2.8 ± 0.3 17 ± 2 83 ± 12


+ModelP

C

T

T

ML

L

S



loncurry District

40Ar mols(10−15)


36Ar mols(10−15)

84Kr mols(10−18)

129Xe mols(10−18)

Cl mols(10−9)

K mols(10−9)

Br/Cl (10−3) I/Cl (10−6) U mols(10−15)

450 317.4 ± 0.5 317.4 ± 0.5 0.40 ± 0.06 10.4 ± 0.4 0.91 ± 0.03 14.1 ± 0.9 2.8 ± 0.3 16 ± 2 103 ± 22500 169.351 ± 0.001 168.3 ± 0.1 0.242 ± 0.005 5.9 ± 0.2 0.58 ± 0.04 8.1 ± 0.5 0.06 ± 0.01 2.8 ± 0.3 16 ± 2 43 ± 23550 245.0 ± 0.2 239.1 ± 0.7 0.41 ± 0.01 8.5 ± 0.3 0.70 ± 0.03 11.4 ± 0.7 0.4 ± 0.1 3.1 ± 0.3 12 ± 1 8 ± 5600 40.86 ± 0.04 40.86 ± 0.04 0.06 ± 0.01 1.5 ± 0.1 0.22 ± 0.03 0.9 ± 0.1 3.1 ± 0.3 8 ± 1700 45.85 ± 0.01 45.85 ± 0.01 0.16 ± 0.02 2.0 ± 0.2 0.1 ± 0.1 1.2 ± 0.1 2.9 ± 0.3 6 ± 1 69 ± 161100 57.1 ± 0.5 56.0 ± 0.5 0.13 ± 0.01 2.3 ± 0.3 0.28 ± 0.05 2.2 ± 0.1 0.06 ± 0.04 2.7 ± 0.3 12 ± 1 332 ± 251300 2080 ± 3 2011 ± 7 2.97 ± 0.02 62 ± 2 2.7 ± 0.1 97 ± 6 4.1 ± 0.1 2.9 ± 0.3 14 ± 1 3631 ± 2581400 280.5 ± 0.3 270.6 ± 0.9 0.405 ± 0.002 6.3 ± 0.2 13.0 ± 0.8 0.59 ± 0.01 2.2 ± 0.2 10 ± 1 2288 ± 1601600 604 ± 2 586 ± 3 0.78 ± 0.02 11.0 ± 0.4 0.41 ± 0.01 24 ± 2 1.05 ± 0.01 1.5 ± 0.2 22 ± 2 15816 ± 1160

Total 6418 ± 3 6261 ± 9 10.2 ± 0.1 228 ± 4 32 ± 1 276 ± 8 9.4 ± 0.2 22682 ± 1201

ribulation Quarry 02CC82, 64 mg200 190.0 ± 0.0 200.5 ± 0.4 0.70 ± 0.02 28 ± 1 14.2 ± 0.7 3.8 ± 0.3 3.1 ± 0.3 3.7 ± 0.6300 637.5 ± 0.1 637.5 ± 0.1 1.07 ± 0.01 38 ± 2 22 ± 1 39 ± 3 3.2 ± 0.3 11 ± 1 173 ± 166400 858 ± 1 830 ± 3 1.3 ± 0.1 30 ± 1 11.2 ± 0.4 54 ± 4 1.7 ± 0.3 3.0 ± 0.3 9 ± 1500 800 ± 1 688 ± 3 2.1 ± 0.1 21.9 ± 0.8 4.9 ± 0.9 51 ± 3 6.7 ± 0.2 2.6 ± 0.3 10 ± 1600 890 ± 1 880 ± 3 0.9 ± 0.2 23.5 ± 1.3 3.2 ± 0.3 59 ± 4 0.6 ± 0.2 2.6 ± 0.3 8.8 ± 0.9 550 ± 75700 347.06 ± 0.01 320 ± 1 0.8 ± 0.1 16.4 ± 0.6 2.1 ± 0.2 17 ± 1 1.6 ± 0.2 2.5 ± 0.3 6.6 ± 0.8 488 ± 491100 486.8 ± 0.4 465 ± 2 0.39 ± 0.01 6.7 ± 0.4 1.5 ± 0.2 20 ± 1 1.3 ± 0.3 2.4 ± 0.3 6.1 ± 0.7 555 ± 771400 3128 ± 1 2979 ± 6 3.0 ± 0.1 51 ± 2 1.9 ± 0.3 197 ± 13 8.9 ± 0.1 2.4 ± 0.3 7.8 ± 0.8 324 ± 411600 2016 ± 3 1975 ± 8 0.7 ± 0.1 13 ± 1 0.9 ± 0.1 58 ± 4 2.48 ± 0.04 2.0 ± 0.2 5.1 ± 0.5 169 ± 74

Total 9353 ± 3 8974 ± 11 11.0 ± 0.3 227 ± 4 62 ± 2 500 ± 15 23 ± 1 2260 ± 220

ribulation Quarry 02CC85, 73 mg200 474.59 ± 0.01 474.6 ± 0.0 1.3 ± 0.1 36 ± 1 10.7 ± 0.7 2.2 ± 0.1 3.2 ± 0.3300 1237.94 ± 0.01 1239.4 ± 0.3 1.67 ± 0.03 36 ± 1 12.5 ± 0.4 43 ± 3 3.2 ± 0.3 7.3 ± 0.8400 1413.4 ± 0.3 1409 ± 2 2.02 ± 0.02 38 ± 1 5.9 ± 0.2 45 ± 3 0.2 ± 0.1 3.1 ± 0.3 7.4 ± 0.8 1 ± 33500 844.8 ± 0.5 844.8 ± 0.5 1.05 ± 0.04 28 ± 1 2.6 ± 0.1 31 ± 2 3.1 ± 0.3 7.7 ± 0.8 19 ± 19600 793.6 ± 0.2 774 ± 1 1.00 ± 0.03 14.9 ± 0.9 31 ± 2 1.2 ± 0.1 3.3 ± 0.3 5.9 ± 0.6 445 ± 68700 682.5 ± 0.1 673 ± 1 0.86 ± 0.04 15.3 ± 0.7 1.6 ± 0.1 19 ± 1 0.6 ± 0.4 2.8 ± 0.3 4.9 ± 0.51100 1093 ± 3 871 ± 6 1.6 ± 0.1 13.6 ± 0.7 2.3 ± 0.2 39 ± 3 13.3 ± 0.2 3.0 ± 0.3 6.8 ± 0.7 316 ± 411400 4458 ± 7 4255 ± 18 4.11 ± 0.03 62 ± 2 2.8 ± 0.1 193 ± 12 12.1 ± 0.8 2.6 ± 0.3 6.2 ± 0.6 565 ± 861600 2478.2 ± 0.1 2352 ± 2 2.0 ± 0.1 18.6 ± 0.7 0.4 ± 0.2 95 ± 6 7.6 ± 0.2 2.1 ± 0.2 3.6 ± 0.4 172 ± 42

Total 13475 ± 7 12893 ± 19 15.6 ± 0.2 262 ± 4 39 ± 1 498 ± 15 35 ± 1 1519 ± 130

ary Kathleen Fold Beltime Creek 02CC93, 97 mg300 1886 ± 2 1849 ± 7 1.72 ± 0.02 57.6 ± 1.0 18.3 ± 0.7 31.9 ± 0.6 2.25 ± 0.03 1.3 ± 0.1 35 ± 4400 1301 ± 1 1256 ± 4 1.51 ± 0.02 37.8 ± 0.6 4.1 ± 0.2 35.9 ± 0.7 2.67 ± 0.04 1.2 ± 0.1 33 ± 4500 589.8 ± 0.3 571 ± 1 0.735 ± 0.004 18.6 ± 0.3 1.5 ± 0.1 17.6 ± 0.3 1.14 ± 0.04 1.3 ± 0.1 33 ± 4600 394.6 ± 0.1 370 ± 1 0.471 ± 0.006 10.9 ± 0.3 0.2 ± 0.2 11.1 ± 0.2 1.50 ± 0.02 1.1 ± 0.1 32 ± 3 269 ± 45700 197.0 ± 0.4 168 ± 1 0.343 ± 0.003 7.2 ± 0.1 1.1 ± 0.1 4.6 ± 0.1 1.8 ± 0.1 0.88 ± 0.09 29 ± 3 1120 ± 561100 151.4 ± 0.2 149.6 ± 0.5 0.160 ± 0.005 3.8 ± 0.2 0.3 ± 0.1 3.5 ± 0.1 0.11 ± 0.01 1.1 ± 0.1 37 ± 4 172 ± 241400 2133 ± 3 2024 ± 8 2.32 ± 0.01 46.1 ± 1.7 2.0 ± 0.1 71.9 ± 1.4 6.5 ± 0.1 1.1 ± 0.1 27 ± 3 461 ± 24

Total 6653 ± 4 6387 ± 11 7.25 ± 0.03 182 ± 2 27 ± 1 177 ± 2 15.9 ± 0.2 2021 ± 79

ime Creek 02CC96, 91 mg200 191.3 ± 0.3 191.3 ± 0.3 0.37 ± 0.02 16.9 ± 0.2 8.9 ± 0.3 0.58 ± 0.02 2.0 ± 0.2 24 ± 3300 1563 ± 2 1542 ± 5 0.86 ± 0.02 25.9 ± 0.4 10.0 ± 0.3 21.9 ± 0.4 1.27 ± 0.04 2.2 ± 0.2 20 ± 2400 1654 ± 1 1595 ± 5 1.03 ± 0.01 26.6 ± 0.4 4.6 ± 0.2 67.2 ± 1.3 3.6 ± 0.1 2.5 ± 0.3 21 ± 2500 641.9 ± 0.5 596 ± 2 0.48 ± 0.01 10.7 ± 0.2 1.30 ± 0.05 44.1 ± 0.8 2.7 ± 0.1 2.3 ± 0.2 20 ± 2600 144.3 ± 0.2 130.4 ± 0.7 0.16 ± 0.01 2.5 ± 0.1 0.38 ± 0.01 9.6 ± 0.2 0.84 ± 0.05 2.0 ± 0.2 19 ± 2700 31.08 ± 0.03 30.6 ± 0.1 0.041 ± 0.002 0.78 ± 0.01 0.18 ± 0.01 1.38 ± 0.03 0.03 ± 0.01 2.4 ± 0.2 14 ± 21100 49.4 ± 0.1 45.9 ± 0.2 0.08 ± 0.01 1.23 ± 0.02 0.10 ± 0.00 3.1 ± 0.1 0.21 ± 0.02 2.2 ± 0.2 14 ± 2 44 ± 31400 1982 ± 2 1743 ± 7 1.48 ± 0.02 26.5 ± 0.4 1.28 ± 0.05 146.0 ± 2.8 14.2 ± 0.2 1.8 ± 0.2 15 ± 2 117 ± 121540 726.9 ± 0.8 644 ± 3 0.54 ± 0.02 10.5 ± 0.2 0.56 ± 0.02 46.9 ± 0.9 5.0 ± 0.1 1.5 ± 0.2 10 ± 1 118 ± 6

Total 6983 ± 3 6518 ± 11 5.05 ± 0.05 122 ± 1 27 ± 1 341 ± 3 27.8 ± 0.2 278 ± 13

unrise Quarry 02CC62, 69 mg200 288.3 ± 0.4 288.3 ± 0.4 0.23 ± 0.01 8.3 ± 0.4 5.0 ± 0.1 1.2 ± 0.1 4.0 ± 0.4 19 ± 2 69 ± 14300 3274 ± 3 3258 ± 11 1.21 ± 0.02 44 ± 2 17.9 ± 0.5 27 ± 2 0.97 ± 0.02 3.9 ± 0.4 21 ± 2 32 ± 31400 2504 ± 3 2496 ± 9 0.83 ± 0.01 24.5 ± 0.9 5.6 ± 0.1 20 ± 1 0.49 ± 0.02 3.4 ± 0.4 22 ± 0 71 ± 20


500 1679 ± 2 1669 ± 5 0.429 ± 0.005 10.0 ± 0.4 1.5 ± 0.2 14.1 ± 0.9 0.60 ± 0.02 3.3 ± 0.3 25 ± 3 7 ± 24600 770 ± 1 762 ± 3 0.25 ± 0.01 5.7 ± 0.5 1.2 ± 0.1 6.0 ± 0.4 0.5 ± 0.1 3.1 ± 0.3 31 ± 3700 176.7 ± 0.1 176.7 ± 0.1 0.04 ± 0.01 1.4 ± 0.1 0.3 ± 0.1 0.69 ± 0.05 3.0 ± 0.3 26 ± 3 46 ± 191100 798 ± 1 793 ± 3 0.20 ± 0.02 3.8 ± 0.2 0.49 ± 0.01 3.6 ± 0.2 0.27 ± 0.01 2.7 ± 0.3 25 ± 3 165 ± 151400 4736 ± 5 4670 ± 16 1.13 ± 0.02 27 ± 1 2.2 ± 0.1 48 ± 3 3.9 ± 0.1 2.7 ± 0.3 32 ± 3 1226 ± 91


+ModelP

1

C

K

K

A

M

T

T

T

K

N



loncurry District

40Ar mols(10−15)


36Ar mols(10−15)

84Kr mols(10−18)

129Xe mols(10−18)

Cl mols(10−9)

K mols(10−9)

Br/Cl (10−3) I/Cl (10−6) U mols(10−15)

1600 1489 ± 1 1470 ± 4 0.54 ± 0.01 10.4 ± 0.4 1.8 ± 0.1 13.2 ± 0.9 1.13 ± 0.03 2.8 ± 0.3 23 ± 2 412 ± 30

Total 15714 ± 7 15583 ± 22 4.87 ± 0.04 134 ± 2 36 ± 1 134 ± 4 7.8 ± 0.1 2028 ± 110

nobby Quarry 02CC108, 81 mg200 2154 ± 2 2161 ± 6 1.46 ± 0.05 31 ± 2 7.3 ± 0.5 6.2 ± 0.4 1.4 ± 0.2 20 ± 3 228 ± 195300 10707 ± 9 10625 ± 30 2.71 ± 0.02 67 ± 3 11.4 ± 0.4 34 ± 2 4.9 ± 0.1 1.4 ± 0.1 19 ± 2400 5056 ± 2 4993 ± 10 1.8 ± 0.1 28.7 ± 1.2 4.5 ± 1.0 26 ± 2 3.8 ± 0.2 1.2 ± 0.1 14 ± 1 306 ± 158500 2648 ± 3 2598 ± 9 1.2 ± 0.1 19.0 ± 0.7 1.0 ± 0.1 35 ± 2 3.0 ± 0.2 0.70 ± 0.07 7.7 ± 0.8 528 ± 131600 2183 ± 3 2158 ± 8 1.3 ± 0.1 19.5 ± 0.8 1.1 ± 0.2 62 ± 4 1.5 ± 1.0 0.43 ± 0.05 5.7 ± 0.6 543 ± 49700 1454 ± 2 1387 ± 6 0.2 ± 0.1 13.0 ± 0.6 2.1 ± 0.8 48 ± 3 4.0 ± 0.4 0.57 ± 0.06 5.5 ± 0.6 1366 ± 4121100 1292 ± 1 1060 ± 4 0.44 ± 0.02 11.9 ± 0.6 0.7 ± 0.5 50 ± 3 13.8 ± 0.3 0.42 ± 0.04 3.8 ± 0.4 1485 ± 1331400 3944 ± 1 3645 ± 8 1.3 ± 0.1 23 ± 2 2.2 ± 0.2 103 ± 7 17.9 ± 0.4 0.69 ± 0.07 7.8 ± 0.8 1067 ± 771600 2108 ± 1 1832 ± 7 1.05 ± 0.01 13.1 ± 0.6 1.3 ± 0.2 73 ± 5 16.5 ± 0.4 1.3 ± 0.1 7.1 ± 0.7 1390 ± 104

Total 31546 ± 10 30460 ± 37 11.5 ± 0.2 226 ± 4 31 ± 2 438 ± 11 65 ± 1 6913 ± 536

nobby Quarry 02CC38, 91 mg200 1397 ± 2 1392 ± 5 0.81 ± 0.01 18.9 ± 0.3 4.4 ± 0.2 1.17 ± 0.02 0.33 ± 0.01 1.3 ± 0.1 12 ± 2300 22950 ± 16 22803 ± 61 3.64 ± 0.03 70 ± 1 7.1 ± 0.3 35.3 ± 0.7 8.8 ± 0.2 1.3 ± 0.1 11 ± 1 133 ± 32400 7503 ± 6 7434 ± 22 1.24 ± 0.01 25.9 ± 0.4 2.55 ± 0.09 25.7 ± 0.5 4.1 ± 0.1 1.2 ± 0.1 10 ± 1 22 ± 14500 4960 ± 4 4901 ± 14 1.08 ± 0.02 18.1 ± 0.3 1.21 ± 0.04 24.8 ± 0.5 3.5 ± 0.1 1.3 ± 0.1 11 ± 1600 3552 ± 3 3500 ± 10 0.57 ± 0.01 12.7 ± 0.3 0.78 ± 0.05 24.6 ± 0.5 3.1 ± 0.1 0.91 ± 0.09 8.8 ± 0.9 78 ± 24700 552.0 ± 0.3 519 ± 1 0.10 ± 0.01 3.3 ± 0.1 0.29 ± 0.01 5.1 ± 0.1 2.0 ± 0.0 0.74 ± 0.08 6.1 ± 0.7 18 ± 21100 890 ± 1 840 ± 3 0.211 ± 0.002 3.8 ± 0.1 0.27 ± 0.01 7.4 ± 0.1 2.96 ± 0.05 1.0 ± 0.1 9 ± 1 142 ± 91400 13062 ± 10 12684 ± 36 3.36 ± 0.03 59.1 ± 0.9 2.44 ± 0.09 140 ± 3 22.7 ± 0.3 0.94 ± 0.10 7.1 ± 0.8 218 ± 211540 3100 ± 2 2960 ± 8 0.77 ± 0.01 8.9 ± 0.5 1.01 ± 0.04 48.7 ± 0.9 8.4 ± 0.1 0.64 ± 0.07 3.5 ± 0.4 151 ± 8

Total 57966 ± 21 57032 ± 77 11.77 ± 0.05 221 ± 2 20.0 ± 0.4 313 ± 3 55.9 ± 0.4 762 ± 49

.3. Noble gas and halogen in vacuo crushing data

ary Kathleen Fold Belt

40Ar mols (10−15) 40Arcorr mols (10−15) 36Ar mols (10−15) 84Kr mols (10−18) 129Xe mols (10−18) Cl mols (10−9) K mols (10−9) Br/Cl (10−3) I/Cl (10−6) U mols (10−15)

ribulation Quarry 02CC05, 22 mgcr 1 887.3 ± 0.6 876 ± 2 2.2 ± 0.2 37 ± 2 1.8 ± 0.6 30 ± 2 0.7 ± 0.2 3.9 ± 0.4 12 ± 1cr 2 988.2 ± 0.4 982 ± 2 1.3 ± 0.1 35 ± 2 1.81 ± 0.04 43 ± 3 0.3 ± 0.1 3.1 ± 0.3 16 ± 2 115 ± 8cr 3 405.0 ± 0.3 402 ± 1 0.8 ± 0.1 16.9 ± 0.6 1.2 ± 0.1 19 ± 1 0.15 ± 0.01 2.7 ± 0.3 14 ± 1 195 ± 19cr 4 325.1 ± 0.1 322.3 ± 0.6 0.3 ± 0.1 13.8 ± 0.5 0.5 ± 0.1 16 ± 1 0.17 ± 0.01 2.9 ± 0.3 13 ± 1 53 ± 96

2605.7 ± 0.8 2583 ± 3 4.6 ± 0.2 102 ± 3 5.2 ± 0.6 109 ± 4 1.3 ± 0.2 363 ± 98

ribulation Quarry 02CC82, 34 mgCr1 1428.9 ± 0.5 1413 ± 3 2.6 ± 0.1 61 ± 3 3.1 ± 0.4 79 ± 5 0.92 ± 0.11 4.6 ± 0.5 10 ± 1Cr2 1949.1 ± 0.7 1913 ± 4 2.88 ± 0.03 77 ± 3 2.4 ± 0.1 105 ± 7 2.2 ± 0.1 3.8 ± 0.4 13 ± 1 29 ± 97Cr3 906.4 ± 0.5 854 ± 2 0.8 ± 0.1 24 ± 1 0.7 ± 0.1 63 ± 4 3.1 ± 0.1 3.7 ± 0.4 10 ± 1Cr4 846.8 ± 0.5 847 ± 2 0.517 ± 0.003 24 ± 3 2.9 ± 0.1 62 ± 4 3.8 ± 0.4 11 ± 1

5131 ± 1 5028 ± 6 6.8 ± 0.1 186 ± 5 9.2 ± 0.5 308 ± 10 6.2 ± 0.2 29 ± 97

ribulation Quarry 02CC85, 47 mgCr 1 1680.7 ± 0.1 1656 ± 2 2.99 ± 0.02 58 ± 2 2.0 ± 0.2 61 ± 4 1.5 ± 0.2 3.8 ± 0.4 8 ± 1 124 ± 29Cr 2 1833.8 ± 0.2 1838 ± 2 2.5 ± 0.1 47 ± 2 2.6 ± 0.3 79 ± 5 3.8 ± 0.4 8 ± 1Cr 3 966 ± 2 961 ± 4 1.11 ± 0.01 22 ± 1 3.6 ± 0.3 47 ± 3 0.3 ± 0.1 3.9 ± 0.4 6 ± 1Cr 4 1081 ± 3 1081 ± 3 0.86 ± 0.02 21 ± 1 0.9 ± 0.3 55 ± 4 3.8 ± 0.4 8 ± 1

5561 ± 4 5536 ± 6 7.5 ± 0.1 148 ± 3 9.1 ± 0.6 242 ± 8 1.8 ± 0.2 124 ± 29

nobby Quarry 02CC108, 26 mgCr1 3219 ± 2 3194 ± 8 1.8 ± 0.1 33 ± 1 1.2 ± 0.4 14.1 ± 0.9 1.54 ± 0.02 1.5 ± 0.2 25 ± 3 433 ± 62Cr2 5052.7 ± 0.9 5031 ± 7 1.1 ± 0.2 21.9 ± 0.8 2.9 ± 0.2 19 ± 1 1.3 ± 0.1 1.7 ± 0.2 25 ± 3


Cr3 1404.1 ± 0.5 1347 ± 3 0.8 ± 0.2 8.0 ± 0.6 0.7 ± 0.1 9.4 ± 0.6 3.4 ± 0.5 1.3 ± 0.1 18 ± 2Cr4 1951.7 ± 0.1 1920 ± 2 0.4 ± 0.2 7.1 ± 0.6 14.2 ± 0.9 1.9 ± 0.3 1.4 ± 0.1 20 ± 2

11628 ± 2 11491 ± 11 4.0 ± 0.3 70 ± 2 4.9 ± 0.5 56 ± 2 8.2 ± 0.6 433 ± 62

b, these sample splits were not subjected to stepped heating.


IN+ModelP

brian

R

A

A

B

B

B

B

B

B

B

B

B

B

C

d

D

F

F

F

F

F

G

H

H

H

H

H

I

J

K

K

K

K

K

K

K

K

K

M

M



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