PROCEEDINGS OF THE 6TH INTERNATIONALSYMPOSIUM ON WATER-ROCK

INTERACTION/MALVERN/3-8 AUGUST 1989

Water-Rock Interaction

WRI-6

Edited by

DOUGLAS L.MILESBritish Geological Survey, Wallingford

universitAtsbibliot hekhan1.o'",,:r

TEO'NlfiGHENlfORMATIOi \V MWOTHEK

A.A.BALKEMA /ROTTERDAM /BROOKFIELD /1989

Water-Rock Interaction, Miles (ed), © 1989 Balkema, Rotterdam. ISBN 9061919703

Contents

Natural diagenesis: A model for artificial diagenesis during steam-assisted recovery ofheavy 1oil, Cold Lake, Alberta, CanadaHugh JAbercrombie, Maurice Shevalier & Ian KHutcheon

Heavy metal transport and retention in porous media - Relation between possibilities of 5parameter estimation from laboratory experiments and hydrogeochemical nature ofwater-rock exchange processesTAbraham, H'Jordan & RHaefher

The applicationofsmall-angle neutron scattering to the study ofmass transfer in clays 9AJAllen, AMBaston, PJ.Bourke & NLJejferies

Dissolution offeldspar: The first step 15EgonAlthaus & Editha Tirtadinata

Radon and helium modelling ofan HDR geothermal reservoir 19J.NAndrews &N. Hussain

Natural ion-chromatography during fresh-/sea water displacements in aquifers; A 23hydrogeochemical model ofthe pastCAJAppelo, LPonten & HJZ.Beekman

Metamorphic fluid migration through grain boundary during a contact metamorphism 29YorkoArita & Hideki Wada

Surface geochemical studies ofgeothermal areas without springs 33HalldbrArmannsson

Chlorine andboron in natural waters in Iceland 37SArndrsson, S.R.Gislason, KGestsdottir & N.dskarsson

Application ofthe quasi-stationary state approximation to interpretwater-rock interactions in 41

open hydrothermal systemsR.CArthur

3He/*He-ratios as indicators ofthe origin ofhelium in groundwater Examples from the deep 45Nagra boreholes inNorthern SwitzerlandWBalderer & BELehmann

Variations ofthe permeability and fine particle migrations in unconsolidatedsandstones 49submitted to saline circulationsJ.Baudracco

VII

Effects of nonhydrostatic stress at the solution-solid interface 55

Brian Bayly

Quantitative modelling of granite water interactions: Application to Stripa mine waters 59

CBeaucaire, D.Grimaud & GMichard

Effluent-ignimbrite interactions at Kinleith, New Zealand 65

ARBell, A.P.W.Hodder & W.EBardsley

Silica-organic complexes and enhanced quartz dissolution in water by organic acids 69

Philip CBennett & DonaldI.Siegel

A new model for atmospheric oxygen over Phanerozoic time 73

RobertABerner & DonaldE.Canfield

Studies of the near-surface spatial and depth distributions ofuranium sorbed onto granite 75

mineral assemblagesJABerry, N.LJefferies & AXLittleboy

Geochemical monitoring of thermal oil recovery processes using produced water chemistry 79

G.WBird, WD.Gunter & EKPerkins

The origin ofhigh sodium bicarbonate waters in the Otway Basin, Victoria, Australia 83

Roger Blake

Sedimentation and early sulfide diagenesis ofthe Harmon Member (Peace RiverFormation), 87

Western Canada

JBloch

Early diagenetic processes and fluid flow: Evidence from stable isotopic composition of 91

authigenic carbonates, Harmon Member (Peace River Formation), Western Canada

JBloch, l.EMutcheon & H.R.Krouse

Retardation ofdissolved radionuclides in consolidated sedimentary rocks - The influence of 95

MgCl2 brine

WBode & CWolfrum

Synthetic fluid inclusions: A novel technique for experimental water-rock studies 99

RobertJBodnar

Ore fluid-rock interaction and mass transferwithin Au-As-Sb mineralized shearzones: 103

Characterization and modelling on the example ofthe MassifCentral (France) depositsM.CBoiron & M.Cathelineau

A kinetic model for the dissolution ofborosilicate glass 107

William LBourcier, K.G.Knauss & Celial. Merzbacher

Adsorption of cadmium onsoils: Kinetics and reversibility 111

ACMBourg &AGadalia

Fluids in metamorphic rocks: Effects of fluid chemistry onquartz microcrack healing 113

SLBrantley & D.Voigt

Mercury, arsenic, antimony, radon and helium in ground waters and fumaroles from the 117

Vulcano Island

Mauro Brondi & Mario DaWAglio

VIII

Adsorption, precipitation and coprecipitation of trace metals on carbonate minerals at low 121

temperatures

JBruno, LCharlet, S.Carrol, RXarthein, ASandino & P.Wersin

The geothermal area ofthe Tirso Valley (Sardinia, Italy) 125R.Caboi, R.Cidu, A.Cristini, LFanfani & PZuddas

A yearly survey ofrain waterdepositions in Southern Sardinia (Italy) 129R.Caboi, ACristini, LFanfani, EFrau, R.Pinna & PZuddas

Quartz dissolution inmicrofractured crystalline rocks: Physical and chemical conditions, 133

thermodynamical modelling ofthe process, and fluid migration reconstruction

M.Cathelineau & MLespinasse

Pressure-temperature-fluid composition changes from magmatic to presentday stages in the 137

Larderello geothermal field (Italy)M.Cathelineau, C.Marignac,A.Valori,J.Dubessy, G.Gianelli & MBuxeddu

Tourmalinites from hydrothermal systems related to Permian riftmagmatism ofthe 141

Hercynian Saalianphase in Tuscany (Italy)G.Cavarretta, M.Puxeddu, M.Franceschelli, EBandeli &AValori

Groundwater contribution to surface runofffrom the small forested catchment - Mlynaruv 145Luh (Czechoslovakia)J.Cerny & G.Kacura

Geochemistry, oxygen andhydrogenisotope ratios ofthermal springs, western continental 149

margin ofIndia - Field and experimental results

D.Chandrasekharam, R.Ramesh & JBalasubramanian

Fluid inclusion and stable isotope studies in the Kawerauhydrothermal system, New 155

Zealand: Evidence for pastmagma-fluid interaction in the active systemB.W.Christenson

Hydrothermal metamorphism in deep-sea trenches of theWestern Pacific 159O.V.Chudaev & lATararin

Travertines: Distribution coefficients of divalent cations between calcites and depositing 163

waters

R.Cidu, LFanfani, PZuddas & P.PZuddas

Tectonic-hydrotherrnal Au-Cu mineralization in a metamorphic-meteoiic fluid mixing zone, 167

Westland, New Zealand

D.Craw, R.D.Johnstone& M.S. Rattenbury

Etch-pit size and shape distribution on orthoclase and pyriboles associated with soil depthand 171

drainage in loess soils

RLCremeens, R.G.Darmody, UJansen & LDJSlorton

Origin ofgases in Variscanmassifs ofEurope 177F.D'Amore,R.Fancelli, S.Nuti, GMichard & T.Pa£es

Ion budgets in a catchment-Natural and anthropogenic contributions 181

OMDanelon & LMMoreiraNordemann

IX

Barite authigenesis in surficial soils ofmid-continental United States 183

R.GDarmody, S.D.Harding & LlHassett

Sorption and coprecipitation ofarsenate by ferrihydrite 187

JADavis, CCFuller, BA.Rea & R.G.Claypool-Frey

Partition coefficients (Rd) for the U series radionuclides in ion exchange sites and amorphous 191

Fe phase in illite and granite samplesJ.P.L.Dearlove, MJvanovich & D.C.Green

Isolation and characterization ofnatural colloids, particularly humic substances, present in a 197

groundwaterThierry Dellis & Valerie Moulin

Isotopic variations of H13C03" as indicator ofdissolution and precipitation ofcalcite in the 203

unsaturated zone ofthe chalk [LDever, MMoulin & P.Vachier

THERMMEOS: Thermodynamic database for computerphysicochemical modelling in 207

geologyPlDorogokupets, WLashkevich & I.K.Karpov

Mineral weathering rates in acid-sensitive catchments: Extrapolation oflaboratory 211

experiments to the field

JlDrever & N.Swoboda-Colberg

Altered layers on dissolving albite- 2. Model 215

CarrickM.Eggleston & RolandHellmann

Geochemical fluxes during shale diagenesis, an example from the Ordovician ofMorocco 219IJ.Evans

Mixing ofsaline basinal fluids in Southern Ontario: Implications of rock-water interaction, 223

hydrocarbon emplacement and Canadian Shield brines

S.K.Frape, P.S.Dollar, B.SherwoodLollar & R.H.McNutt

Evolution of a groundwater-recharge scenario for the Waterloo aquifer during 13 years of 227

chemical and isotopic analysesSteven J.Fritz, RobertJ.Drimmie & PeterFritz

Chemical weathering rates at the RAIN catchments in Norway 231

ToreFrogner

Modeling simple cement-water systems using the speciation/solubility/reaction path 235

computer codes EQ3NR/EQ6, with specific application to nuclearwaste repositoriesMarkA.Gardiner, Stephen RAlcorn, Jonathan Myers & Craig AGivens

Application of a reinjection technique to Dickson hydrothermal experiments: The effect of 239introducing fresh solution to the basalt-water system at 300°C and 30 MPaMAGardiner, G.C.Ulmer & DE.Grandstaff

Evidence for penetration of sedimentary basin brines into an Archean granite ofthe Canadian 243Shield

M.Gascoyne, APurdy, PFritz, J.D.Ross, S.K.Frape, RJ.Drimmie & RKBetcher

x

Soluble salts in a Canadian Shield granite as contributors to groundwatersalinity 247

M.Gascoyne, J.D.Ross, R.LWatson & D.CKamineni

The chemical structure of arid zone groundwaters: Role of aeolian transport, surface flow and 251

ofgeochemical processes prior to recharge and following dischargeJoelR.Gat

Geology and hydrogeology ofnorthern Switzerland 255AGautschi

Processes controlling C02- and Cl-contents of thermal discharges from theTaupo-Rotorua 259

volcanic-magmatic-hydrothermal system, New Zealand

W.F.Giggenbach

Kinetics ofwater-air interactions in rivers: A field study in Iceland 263

Sigurbur Reynir Gislason

Ion microprobe analysis of rock-forming minerals from the Carnmenellis Granite 267

DAGoossens, LVan 'tdack & R.Gijbels

A SMS, XPS, SEM, TEM andFTIR study offeldspar surfaces after reacting with acid 271

solutions

D.A.Goossens, A.P.Pijpers, J.CPhilippaerts, S.Van Tendeloo, EAlthaus & R.Gijbels

Hydrogeochemical experiments on aquifer thermal energy storage: Injection ofheated 275

groundwater in a sediment column

Jasper Griffioen, CAnthony J. Appelo & Martin van der Weiden

The Jade hydrothermal field in the Okinawa Trough -First discovery ofmassive sulphides in 279

an intracontinental back-arc basin

PHalbach, MWahsner, LKaselitz, HSakai & UHein

Magmatic-hydrothermal origin for fluids involved in the generation ofmassive sulphide 285

deposits at Rio Tinto, SpainCarol EHalsall & FrederickJSawkins

Modelling acid stimulation of the Halfway Formation, Canada, using REACTRAN, a 289

geochemical computer model

Helen FCHaskin, Tim J.Hart, Wilson KMartir,Robert MMoss, Jon SDudley & CraigHMoore

Altered layers on dissolving albite. I. Results 293

RolandHellmann, CarrickM.Eggleston, MichaelFHochella, Jr. & DavidACrerar

Some nonequilibrium redox processes in water-rock interaction 297

J.DMem

A geochemical model of calcite precipitation and C02 outgassing in karst streams 301

JanetSHerman

Ionic control in deterioration ofbuilding materials 305

Peter PMudec

Aqueous solution reactions ofhydrocarbonreservoir clays: Kaolinite, smectite, illite, chlorite 309

CREughes, R.CDavey & CD.Curtis

XI

Clay mineral characterisationby analytical transmission electron microscopy: Problems and 313

perspectivesC.R.Hughes & JAWhiteman

Helium isotope studies in the Taupo Volcanic Zone, New Zealand 317John R.Hulston & John ELupton

The role ofsilicate hydrolysis in the origin of C02 in sedimentary basins 321Ian EHutcheon & HughJAbercrombie

Experimental modelling of cassiterite-water system 325.P.VJvashov

Microscopic distribution oftrace elements inminerals (chlorites, sulfides, sulfates) in 327

submarine hydrothermal systemsD.RJanecky, RMEaymon, TMBenjamin, P.S.Z.Rogers & GXBayhurst

Hydrogen isotope kinetics during hydrothermal alteration in SW Connemara, Ireland 331G.RJJenkin & A.E.Fallick

Palagonitization ofdeep sea dredge sample glasses 337MJJercinovic, TMurakami & R.CEwing

Normative analysis ofgroundwaters from the Madrid Basin, Spain 341Blair FJones & MBamon Llamas

Interactions between meltwater and organic-rich particulate material in boreal forest 349snowpacks: Evidence for bothphysico-chemical andmicrobiological influencesH.GJones & M.Tranter

Monitoring the evolution of alteration minerals and fluids during a hydrothermal experiment 353GHXacandes, G.C.Ulmer & DRGrandstaff

Microstructural andmineralogical evolution offracture zones in granites due to water-rock 357interactionD. ChoudariKamineni

Fluid interaction characteristics of two granitic plutons in the Superior Province, Canadian 361Shield

D.CXamineni, RXerrich & Z.E.Peterman

Equilibrium exchange models for chlorine stable isotope fractionation in high temperature 365environmentsRonaldSXaufmann

The interaction of gypsum particles with salt solutions in equilibrating systems 369Perla Kaushansky & Shmuel Yariv

Hydrothermal fluids in oceanic crust-seawater interaction from Troodos ophiolite 373HXawahata, S.D.Scott & MXusakabe

Chemical transport during fumarolic alteration, cooling, and weathering, Valley of Ten 377Thousand Smokes, Alaska

T.E.CXeith, CHeropoulos & T.S.Presser

XII

Field and laboratory studies of transport ofreactive solutes in groundwater 381DBXent, JADavis, ASMaest & BARea

Origin of water and solutes in granitic rocks at Cajon Pass, California, USA 385YXXharaka, W.CEvans, GAmbats & LD.White

Silicate and chloride complexes - The basic factor of their migration and geochemical cyclic 389recurrence

ANXozin

Manganese and iron in saline groundwater and geothermal brines inIceland 393Hrefna Kristmannsdottir & Magnus dlafsson

Copper-arsenic mobilization and attenuation in an acid mine drainage environment 397Y.TJohn Kwong & DXirkNordstrom

Radiogenic properties of Finnish groundwaters 401

P.WLahermo

Deep groundwater conditions at Miihkali, eastern Finland 405

P.WLahermo, S.Halonen,LAhonen, KBirttisalo & JMitrega

Mapping of low enthalpy brines in Denmark forgeothermal exploitation 409

7i oelsLaier

The influence of fracture mineral/groundwater interaction on themobility ofU, Th, REE and 413other trace elements indifferent redoxenvironments

O.Landstrom & E.-L.Tullborg

Nuclide sorption on heterogeneous natural surfaces 417

HLang & C.Wolfrum

Unidimensional transport of stable isotopes: The shapes of geochemical fronts 421

Keith RLassey & PeterBlattner

The geometry ofFe3+ and Fe2+ variations around fractures in weathered granite 425AGLatham

Subsurfaceproduction of3He, "He, 36C1,37Ar, 39Ar, 40Ar, 129I and ^Rn inthe crystalline 429

basementand the sediments ofNorthern Switzerland

BBLehmann & HELoosli

Experimental determination ofthe fractionation factors ofXHco3-co2(g)> ^co3-co2(g)at 25° and 433

40°C

PMLesniak&HSakai

The isotopic composition ofhydrogen and oxygen ofbrines in China 437Li Guiru

A Sr isotopic study ofthe Eye-Dashwa Lakes pluton, Ontario and the Lac du Bonnet pluton, 441

Manitoba: Plagioclase/water reaction

WLi, M.T.Franklyn, REMcNutt, HPSchwarcz, M.Gascoyne, D.C. Kamineni & SXFrape

Transfer ofunderground produced37Ar,39Ar and *°Arfrom rock into water 445

HELoosli& B.E.Lehmann

XIII

The role of organic matter in the fixation of sulfur in freshwater lake sediments 449AJLosher & XRXelts

Sources of lithium and barium in Gulfof Mexico Basin formation waters, USA 453

GLMacpherson

Boron in saline brines, GulfofMexico sedimentary basin, USA 457

GLMacpherson & L.S.Land

Simulation of granite dissolution at 25, 60 and 100°C based on thermodynamic potential and 461

kinetic laws

Benoit Made & BertrandFritz

On a high saline brine ofmeteoric origin from Ohdo, Gunma, Japan 465

OMatsubaya & Y.Sakai

Gaspressures at the Geysers geothermal field, California: Comparison with liquid-dominated 469

systems and implications for reservoir conditions

RAMcCartney & JREaizlip

U, Th, REE mobilization during water-rock interactions in a U-mineralized granite 475

M.-T.Menager, C.Menet, J.-CPetit & B.Come

Metadomains as indicators of fluid-rock interaction in the Welsh Marginal Basin 479

RMetcalfe

Chlorine-36 in deep groundwaters and host-rocks ofNorthern Switzerland: Sources, 483

evolution andhydrological implicationsJLMichelot, J.Ch.Fontes, SSoreau, B.E.Lehmann, HELoosli, WBalderer, DElmore,P.WXubik, W.Wolfli, JBeer & ASynal

A modelling approach for estimating long-term and seasonal CaC03 dissolution rates 487

M.W.Milke&MJ.Small

The authigenesis ofphosphate minerals in some Norwegian hydrocarbon reservoirs: 491Evidence for the mobility and redistribution of rare earth elements (REE) and Th duringsandstone diagenesisAEMilodowski &. AEurst

Interstitial water-rock interaction in the unsaturated zone of a Permo-Triassic sandstone 495

aquiferPD.Moss & W.M.Edmunds

Strontium distribution coefficient as indicator of dissolution-precipitation processes in the 501chalk

MMoulin, LDever & P.Vachier

Chemical processes atthe mineral oxide-water interface: System ALPj-Organic 505

matter-Am(IH)Valerie Moulin, Denise Stammose & Tuan Manh Tran

Weathering degree of granitic rocks as studied by X-ray diffractometry and diffuse 511reflectance spectroscopyTetsushi Nagano & Satoru Nakashima

XIV

Aluminium weathering/ion exchange for acid impacted systems: The Achilles heel of 515

predictive models?Colin Neal

Application ofa cation exchange mass-balance model to the interpretation ofsaline 521

groundwater chemistry evolved from Holocene seawaterentrapped inrapakivi granite at

Hastholmen, Finland

Darrell Kirk Nordstrom

An attempt to determine 180/160 ratios of framework silicate oxygen of apophyllite and 525

wairakite

MasamiNoto, MinoruKusakabe & Masahiro Kometani

Cooling rate ofhydrothermal quartz 529

T.Ohba & KXazahaya

Chemistry ofdiagenetic zeolite in a shallow, coal-bearing sedimentary pile, NE Japan 533

Yasuko OkuyamaXusunose

The influence ofvolcanic activity on groundwater chemistry within the Namafjall geothermal 537

system, North Iceland

Magnus Olafsson & HrefnaKristmannsdottir

Modeling chemical equilibrium in hydrothermal systems, with examples from Iceland and 541

China

PangZhonghe & Hallddr Armannsson

Uncertainty analyses of models of ground-water carbonate isotope evolution 545

F.J.Pearson, Jr.

Hydrogeochemical dynamics of interstitial waters in the bottom sediments in the deep Black 549

Sea zone

E.N.Pentcheva & M.G.Damyanova

Applications of SOLMINEQ.88 and SOLMINEQ.88 pc/shell 553

EEPerkins, W.D.Gunter & G.WBird

The interaction of brines and permafrost 557

EMPinneker, S.VAlekseev & VKBorisov

The influence ofdeepmeteoric invasion on the reservoir quality ofCretaceous sandstones in 561

the Mackenzie Delta, Canada

DJBotocki

An infiltration mirabilite deposit and related brine (Lixian, Hunan province, China) 565

Qu Yihua

Kinetics ofdissolution ofheulandite at 25°C 567

Kristin ValaRagnarsdottir

The effect ofiron and magnesium on the stability ofillite and smectite 569

UrsRaz & TjerkPeters

Cooling in Philippine geothermal systems 573

Agnes GReyes

xv

Rate ofplagioclase dissolution in the Camborne School ofMines experimental hot dry rock 577geothermal system, Rosemanowes, Cornwall

Hugh G.Richards & David Savage

A comparison ofpyrite oxidation rates inbatch, mixed flow, and plug flow reactors 581J.Donald Rimstidt & William DEewcomb

A vertical thermal gradient experiment to simulate conditions in vapor dominated geothermal 585systems, epithermal gold deposits, and high level radioactive repositories in unsaturatedmedia

J.DonaldRimstidt, William DEewcomb & Donald LShettel, Jr.

Mineralisation, fluid inclusion and sulphur isotope studies ofthe Thames-Tapu area, Hauraki 589goldfield, New Zealand

B.WRobinson &R.JMerchant

Experimental simulation of hydrothermal alteration in the Miravalles geothermal system, 593Costa Rica

CARochelle, DSavage & B.W.D.Yardley

Natural clean-up ofa stream contaminated by mine and mill wastes: A reaction analogous to 597liming in water treatment

DonaldDRunnells & John J.Rampe

The Palmottu U-Th deposit in SW Finland as a natural analogue to the behaviour ofspent 601nuclearfuel in bedrock: A preliminary reportTRuskeeniemi, RBlomqvist, SEalonen, TJaakkola, ALindberg, HEiini, J.Suksi,RSuutarinen, B.Soderholm & M.Vesterinen

Acceleration and retardation ofsilicate weathering due to organic substances 605D.Schenk,A.Petersen & GMatthess

Kinetics ofalkali feldspar dissolution at low temperature 609PSchweda

The effect oftemperature on base metal mobility during hydrothermal basalt alteration: 613Implications forme formation of ridge crest hydrothermal fluids and seafloor metal depositsJXSeewald, WESeyfried, Jr., MEBerndt & PJ.Saccocia

Deep gases and brines of the Canadian and Fennoscandian Shields - A testing ground for the 617theory ofabiotic methane generationB.SherwoodLollar, SXFrape, PFritz, SAMacko, S.M.Weise, JA.Welhan, RBlomqvist,P.WLahermo &R.Drimmie

The neutralizing-reduction-mineralizationof uranium 621Shi Wei-jun & PengHai-jun

Mixing diagrams of hydrothermal solutions and their applications to some hydrothermal ore 625deposits in JapanYShibue

"C/^C ratios and origins of ZC02 in alkaline hot-spring waters discharging along fault zones 629in the Abukuma metamorphic belt, Northeast JapanHShigeno&KAbe

XVI

Rare earth element geochemistry and evolution ofsubmarine geothermal system 633accompanied by Kuroko sulfide-sulfate mineralization in JapanN.Shikazono & RMatsumoto

Pressure dependence of mineral-waterreaction equilibrium in the lowpressure range 635Shinohara Hiroshi & Fujimoto Koichiro

Kinetics and non-stoichiometry oflabradorite dissolution 639Lennart Sjoberg

Alteration mineralogy ofthe Elli5aar geothermal field, Reykjavik, Iceland 643OmarBjarki Smarason, Jens Tomasson & Sugiarto Ganda

Alkali metal enrichments in groundwaters from the Carnmenellis area, Cornwall 647Pauline LSmedley

Groundwater contaminant transport with ion exchange in heterogeneous medium 651

LSovadina

Factors controlling trace element levels in groundwaterin The Netherlands 655

PJ.Stuyfzand

The hydrogeochemical characteristics and origin ofthermal waters inJiangxi, southeast 661China

SunZhanxue

Stable isotope measurements on the thermal water at the Nesjavellir and Mosfellssveit 665

geothermal fields, Iceland

Amy Erla Sveinbjornsdottir

Correlation of the chemical composition of water from the unsaturated zone with the 669

mineralogy of a profile on the Sao Paulo Basin, Brazil

M.Szikszay & M.CToledo-Gwke

Dissolution kinetics ofcalcite in CO^H^O systems at210°C 673

S.Talman, B.Wiwchar, WD.Gunter & CMScarfef

Geochemical cycles and global water-rock interaction from 4,000 million years 675

YTardy

Hydrothermal activityon the Mid-Atlantic Ridge 679

G.Thompson, S.E.Humphris, CLalou & PARona

The alteration and diagenesis oftuffs and tuffaceous sediments 683

J.Tomasson

Chemical weathering reactions in Alpine glacialmeltwaters 687

Martyn Tranter, RobRaiswell & Rachel Mills

Graphitization ofcarbonaceous material in sedimentary and metamorphic rocks during 691

metamorphismN.Tsuchiya & T.Chida

8180 and813C in fracture calcite used for interpretation ofrecentmeteoricwater circulation 695

E.-L.Tullborg

XVII

Framework alpha-pentastructures of stresses and their influence of formation of subsurface 699

fluids, hydrocarbons in particularVJ.TyurinAvinsky

Release of heavy metals in groundwater due to manure spreading 703

C.G.E.M.van Beek, FAMEettinga & R.Straatman

Marine apatite precipitation 707

Philippe Van Cappellen & RobertABerner

Composition ofnewly formed minerals from nitrogeneous thermal waters in the Tchepino 711

valley (Bulgaria)LVan' t dack, P.SBetrov, EEPentcheva, E.Veldeman & R.Gijbels

Arsenic in deep groundwater 715

I.Varsanyi

Water-rock interaction in the Southwest Bulgaria granitoid system: A source of trace 719

elements in the thermal waters

E.Veldeman, EEBentcheva,L Van't dack & R.Gijbels

Ahydrothermal model of Los Azufres geothermal system, Mexico 723

Mahendra P.Verma, DEieva, E.Santoyo, RMBarragan, EBortugal & J.LQuijano

Geochemical controls on groundwater chemistry in shales 727

K.L.Von Damm

Electrostatic approach for calculating mineral solubilities and complex formation in 731

supercritical volatile-salt aqueous solutions

J.VWalther&J.Schott

Differentiation in mesostasis andthe effect on the hydrothermal redox buffering capacity of 735

basalt

Jianhua Wang,MAGardiner, D.E.Grandstqff& Gene C.Ulmer

Halogens in apatites, biotites, and hornblendes from the Yuantoushan granitic rocks, 739northeastern Taiwan

Yunshuen Wang & Rueychang Jeng

The paleohydrogeochemical conditions for the genesis of some sedimentary-reworked 743siderite deposits in China

Yanxin Wang & Zhaoli Shen

Formation of biotite accompanying a later fracture system and associated fluid in the Haast 747schists, New Zealand

Teruo Watanabe, RodneyH.Grapes, Yosuke Kawachi, Tetsumaru Itaya & I.M.Turnbull

Surface structure and mineral dissolution kinetics: A Monte Carlo study 751B.Wehrli

Post-crystallization low temperature hydrothermal alteration in Proterozoic Basement ofdie 755Midcontinent of North AmericaDavidB.Wenner

XVIII

Isotopic geothermometry and flow regimes in the Muschelkalk aquifer from northern 761

Switzerland (Nagra deep drilling programme)P.Wexsteen & AMatter

Electron transfer mechanisms associated with the surface dissolution and oxidation of 765

magnetite and ilmenite

Art F.White & Michael FEochella, Jr.

Diverse fluid phases associated with the crystallisation and alteration of lithium pegmatites at 769

Moylisha and Stranakelly, SE Ireland

Martin P.Whitworth & Andrew HRankin

Growth mechanisms of sandstone-hosted calcite concretion growth and implications for 773

growth times

M.Wilkinson

Sorptive interactions between organic micropollutants and the mineral fraction of 777

Permo-Triassic sandstone

D.J.Williamson, DELerner & MAstin

Considerations on sorption behaviour ofcolloids in natural systems 781

C.Wolfrum & HLang

Experimental study about the activation and migration of gold and silver involcanic rocks 785

LiangXiangji & Qiao Li

Chemistry and isotopic composition of fluid from a deep thrust zone, Central Pyrenees 789

B.WD.Yardley, DABanks, GRDavies, AMMcCaig & N.T.Grant

Experimental modelling ofmetasomatic zoning at fluid-rock interaction 793

G.P.Zaraisky

Thermal decompaction ofrocks and its effect on permeability 797

G.PZaraisky, VEBalashov & S.VZonov

The characteristics offluorine in groundwater of North China and the significance of 801

fluorite-water interaction to fluorine transportationShenZhaoli, Zhou Mi & Tang Minggao

Finite element analysis of water seepage in fractured rock masses of dam abutments 805

Weiyuan Zhou & Yanyi Yang

Stable isotope studies of fluids from Xiangshan fossil hydrothermal system 809

Zhou Wen-bin & LiXue-li

Hydrothermal alterationin the Yangying geothermal field ofTibet, China 813

ZhuMeixiang

Author index 817

XIX