江汉盆地潜江凹陷上始新统含盐岩系准原生白云岩的沉积学特征与形成机理

:1671-1505(2006)04-0441-133(No.49833010):2006-04-26:2006-06-2831,21,2341,1000372,1000373,1000834,101149,,,;X,CaCO357130%,0140,;,;3015,44,,301544,Mg/Ca,,,1963,1995,,,E2mail:[e-mail]:P588124+5:ASedimentarycharacteristicsandformationmechanismofpeneprimarydolostoneintheUpperEocenesalt2bearingintervalinQianjiangSag,JianghanBasinZhangYongsheng1,2HouXianhua1,2ZhangHaiqing3YangYuqing41InstituteofMineralResources,ChineseAcademyofGeologicalSciences(CAGS),Beijing1000372KeyLaboratoryofSalineLakeResourcesandEnvironment,CAGS,Beijing1000373PetroleumExplorationandProductionResearchInstituteofSINOPEC,Beijing1000834Logging,Welltech2ChinaOilfieldServiceLtd1,CNOOC,Beijing101149AbstractTheJianghanBasinisatypicalPaleogenesaltlakebasinineasternChina1Micro2crys2tallinedolostoneintheUpperEocenesalt2bearingintervalintheQianjiangSag,JianghanBasiniscomposedofmud2sizedcrystallinedolomite,andthedolomiteisredandorange2redundercathodolu284200611JOURNALOFPALAEOGEOGRAPHYVol18No14Nov12006minescence1Associatedmineralsareprimaryglauberite,haliteandterrigenousmud;whilecalciteisabsentorrare1TheX2raydiffractionanalysisshowsthatthemud2sizedcrystallinedolostonehasanav2erageCaCO3molecontentof57130%andanaveragedegreeoforderof0140,revealingthecharacter2isticsofhighercalciumcontentandlowerdegreeoforder1Itiscloselyintergrownwithglauberite,in2dicatingthattheaqueousmediuminthedepositionalenvironmentofmud2sizedcrystallinedolostonewashypersalinewaterordilutebrine1Thetemperatureofwaterinthedepositionalenvironmentcalculatedaccordingtotheoxygenisotopedataaveraged3015andtheminimumhomogenizationtemperatureofinclusionsinprimaryglauberitecrystalsassociatedwithmud2sizedcrystallinedolomitewas441Thetwogroupsoftemperaturedataareclose,indicatingthatthetemperatureofthewaterinthepale2olakeenvironmentduringthedepositionofmud2sizedcrystallinedolostonerangedfrom3015to44.Thusitmaybeinferredthatthemud2sizedcrystallinedolostoneintheUpperEocenesalt2bear2ingintervalintheQianjiangsagispeneprimarydolostoneformeddirectlybychemicalprecipitationinahigh2temperature,high2salinity,highMg/Caratioandperenniallymeromicticsaltlake1KeywordsJianghanBasin,UpperEocene,salt2bearinginterval,chemicalprecipitation,peneprimarydolostoneAboutthefirstauthorZhangYongsheng,bornin1963,obtainedhisdoctoraldegreein19951NowheisaseniorresearcherattheInstituteofMineralResources,ChineseAcademyofGeo2logicalSciences,andisengagedinthestudyofsaltydepositsandmarinefaciesoilandgasgeology1E2mail:[e-mail]1,(Land,1985),Ca2+Mg2+,Ca50Mg50CO3Ca2+50%,,,,,,,60,:Gebelein(1980),;Mckenzie(1981);Mitchell(1987),,,,,(1986);,,,(,2003),1,442200611,,(1),1Table1StratigraphyofthePaleogeneinQianjiangSag/m3009000100120450,,110700,15064010070017322186001900600200020019001202800(1998)7160(1)(2005)3,9,,(2)(),;();(),,(2)(2004)717,,4:,,,,84:4431(,1998,)Fig11Mapshowingsalinerhythm(2order)divisionforQianjiangFormationofQianjiangSag,JianghanBasin(modifiedfromWangDianfuandWangShizhong,1998)4442006112122Fig12Histogramsedimentarycharacteristicsoftherhythm22ofMember2ofQianjiangFormationinWellWangping122111),,,,,,,10%15%(),,,,2),,,2121)(3-1),80%,,,,5%10%,015%4%,1%5%,,(3-3),(3-2)(),,50%,1%25%,5%25%,1%5%,;,,,,(3-4),2),,,(3-5),,(3-6),,,,,,,3311,84:4453()Fig13Microphotographsofmicro2crystallinedolostone,grain2bearing(glauberite2bearing)mud2sizedcrystallinedolostoneintheQianjiangFormation1,,,,,1,1501144m,,32;2,,10-6,,1494179m,,32;3,,,,,;,1,,1501144m,,32;4,;,,;,,;10-6,,1191183m;,32;5,6,23m,,,44620061118BGaSrBaNiVMn(2),B1m,B2,B18mg/L288mg/L,119mg/L,Ga5mg/L1619mg/L,618mg/L,B/Ga18167;Sr27818mg/L2189mg/L,1529mg/L,Ba3617mg/L62712mg/L,20014mg/L,Sr/Ba8105;V1613mg/L7416mg/L,4015mg/L,Ni419mg/L2711mg/L,1216mg/L,V/Ni3158,BSrV,B/GaV/NiSr/Ba,2(mg/L)Table2Analysisdataoftraceelementscontent(mg/L)ofmud2sizedcrytallinedolostone/mBGaSrBaNiVMnV/NiB/GaSr/BaS1001179125Gb47100546715091130619027120321140319491405112S961186162Gb6410051733102971106160251701881903189121805183S95-11186154210100540115012518014170191804001001135421003119S951189154288100711027818014510015140601204221503191401561192S941190152Gb7410051006691404190161307514031331418014150S8412041522701005218924118016140331701611902106541009105S791210105Gb240100141301708447110221406818020812031071617831821701006160111220215012150361002541003108271206120S72148217536100586216271206130201403411403124712013175S65148515936100566418074190615027140303120412271208188S501498180Gb1810051909230130510044190248150819831608129S48-11499164Gb921007150125514917021180681301291903113121278138S46-1150018710810058151202121108110341205271004122211603184S461501144441005693110152110717027180346170316181804156S34-11508194Gb441005213514114011110401101911303161818015110S281511194Gb11010010190107416711022180611101891702168101096143S25-1151315634100521242921401414074160511130511861807126S241514103120100161906171203617027110641903521702139711016182S121517126Gb901005149696110817030140151190314918100151576710061901946198120121704419029914041071011391901191006180152920014012160401502761703158181678105312,,13C18O,13C18O13C,13C,18O,1