藏南沉错沉积物的粒度特征及其古环境意义

:2002208;:2002208:(KZCX22314)(CXIOG2A1202):(19772),,,,:100726301(2002)0520459209,(,100101):,,1400:593A1D1821A1D1,;821A1D11343A1D1,,,;1343A1D11892A1D1,1602A1D1,(1343A1D11512A1D11670A1D11892A1D1),;1892A1D11998A1D1,,1892A1D1:;;;;:P93117;X144:A1,[1][2],(PAGES),,,,,,903934E,285459N,,148km2,40km2,,21520029PROGRESSINGEOGRAPHYVol.21,No.5Sep.,2002©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.[3],372mm,69,92%;214,102211,(CC1),1cm,8m,800m,115%(1)1CC1Fig11LocationofCC1coreandisobathofChenCo212,,[4]CC1210Pb137Cs[57]210Pb,,,,01130122cmöa0116cmöa,CC1593A1D11400,10(416715a),06421©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.213MALVERNMASTERSIZER2000,10%,10%(),MASTERSIZER200001022000Lm,3[8],,[4,914],,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,(Ri)(SK)(KG)Ri,,,,;SK,,,;KG,,[15],,D[4,3]1645:©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.4,,CC1,(1),,[16],,,,[3],65%,,,,,,,,19611996,,,,;(2),2CC1Fig12ComparisonofmeangrainsizeofCC1coreandprecipitation,airtemperatureinLangkazi26421©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.5CC1CC1,CC1,,,(3),,CC1,,,1400:3CC1Fig13GrainsizeparametersandsedimentaryrateofCC1core(1)216184cm(593A1D1821A1D1),,,,,,,,,,,(2)183114cm(821A1D11343A1D1)500,139131cm(1150A1D11206A1D1),,,,10Lm,,,,,,,1150A1D11206A1D13645:©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.,,,,,(3)11418cm(1343A1D11892A1D1),10Lm150Lm,3,8056cm(1512A1D11670A1D1),67cm(1602A1D1)11480cm(1343A1D11512A1D1)5618cm(1670A1D11892A1D1),1343A1D11512A1D1,,,,,,,,,(4)180cm(1892A1D11998A1D1)100,,1975A1D1,,1892A1D1,,1975A1D1,6CC1,CC1,CaCO3[17](4),,821A1D11343A1D11892A1D1,,[18]CC1,3,108cm(1374A1D1),10818cm(1374A1D11892A1D1),18cm,1970A1D1,[19],1100A1D12000A1D1,1200A1D11400A1D11600A1D11750A1D11960A1D1,,,11418cm,8056cm,,,,,46421©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.[23],,1830A1D1,4CC1Fig14ComparisonofmeangrainsizeandotherindicesofCC1core,,:593A1D1821A1D1,,,CaCO3,;821A1D11343A1D1,,CaCO3,;1343A1D11892A1D1,,,CaCO3,;1892A1D1,,CaCO3,,,,,,,,,,5645:©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.,2000,,,[2024],CC1,821A1D11892A1D1,1343A1D1,,,:,,:[1],,.[J].,2000,45(1):982106.[2],,.[J].,1998,43(6):6332636.[3].[M].:,1984.[4],,.[J].,2000,18(3):3412345.[5].210Pb[J].,1997(3):2302239.[6].137Cs[J].,1999(1):73280.[7]PenningtonW,CambrayRS,FisherEM.Observationonlakesedimentsusingfallout137Csasatracer[J].Na2ture,1973,242:3242326.[8].[M].:,2000.3.[9],,.[J].,2001,21(1):93295.[10],,.[J].,1999,17():7692774.[11],.[M].:,1994.8.[12],.[J].,1999,19(2):1752182.[13],.[J].,1990,35(1):54256.[14]ZhuLiping,ChenLing,LiBingyuanetal.EnvironmentalchangesreflectedbythelakesedimentsoftheSouthHongshanLake,NorthwestTibet[J].ScienceinChina,2002,45(5):4302439.[15],.[M].:,1986.[16].[M].:,1986.10.[17],,.1300[J].,2001,21(6):5202527.[18],,.1400[J].,2002,57(4):.[19],,.[J].,2001,21(6):5082513.[20].[J].,1973(2):1682189.[21],,.2000[J].(B),1994,24(9):99821008.[22].[J].,1993(1):7215.[23],,.[J].,1998(1):54262.[24],,.2000a10a[J].(D),1999,29(1):79286.66421©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.Grain-sizeCharacteristicsandTheirPaleo-environmentalSignificanceofChenCoLakeSedimentsinSouthernTibetWANGJun2bo,ZHULi2ping(InstituteofGeographicalSciencesandNaturalResourcesResearch,CAS,Beijing100101China)Abstract:Grain2sizeisoneoftheusefulindicesinthelacustrinesedimentaryresearch.Bydirectlyindicatingthewaterimpetusduringthesedimentaryperiod,thegrain2sizeoflakesedimentsindirectlyreflectsthesuppliedwatervolumechangesofthelake.Becausethelakewatervolumeisgreatlyinfluencedbyclimaticfactors,suchasprecipitation,tempera2tureandinducedglaciermeltingwater,thegrain2sizeprovidesmoreinformationtoeluci2datetheenvironmentalchanges.Bytheanalysesofthegrain2sizeparametersandthecomparisonwithotherproxiesoftheChenCosediments,fourstagesofenvironmentalchangessinceca.1400yearsagohavebeendistinguished.1)Ca.593821A.D.wasahighlakelevelperiodaccompaniedbyfrequentfluctuations.Itimpliesrelativelywetclimaticconditionswithmulti2timealter2nativechanges.2)Ca.82121343A.D.wasalongandstablewetperiod,duringwhichthelakeenlargedandthelakelevelrose.3)Ca.134321892A.D.wasaclimaticallycomplexperiod.Theinflowwaterviolentlyincreasedaroundca.1602A.D.whilethelakewasintheshallowwaterstatusinotherperiods.Itsuggestedthatthesuppliedwaterofthelakewasrelativelyweak.4)Ca.189221998A.D.wasanotherstableperiodwiththelightlakelevelvariations.Ca.1892A.D.wasanobviousborderlineforshowingthesuppliedwaterimpetuschanges.Theseenvironmentalchangesreflectedbythegrain2sizeofChenColakesedimentswerewellsupportedbyotherproxiesandprovedbyotherresearchresults.Keywords:ChenCo;lakesediments;grain2size;lakelevelfluctuations;environmentchanges7645:©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.