内蒙古银根盆地下白垩统沉积相

:167121505(2003)0120036208X1,2221,7100692,710056,,2000m,,(),,,,,,,1965,,,P512.2A1,,1023010730,404220,,,,400km,130180km,5.4104km2,()()[1](1),,[2],,,,,,,680810m;,,200740m;,,200750m,,205080,X:2002207229:20022092235120032JOURNALOFPALAEOGEOGRAPHYVol15No11Feb12003,,,1Fig.1TectonicunitsmapofYingenBasin2,:2.1(K1b1),,,,:(1):,,,100cm,,,,,,,,13m(2):,,,,,0.31.2m,,,1:37,0.30.8m,,,,2(,K1b1)Fig.2Sedimentarysequenceofalluvialfanfacies,,,,,(2)2.2,,,,:1)(Gm):,,,10cm,0.20.5cm,;2)(Sp):,,1520,2030cm,0.53m,,;3)(St):,,1cm,530cm,,;4)(St):,,0.51cm,0.22m;5)(Sr):,,,;6)(Fl):,,,,,,(3)2.3(),,;,3853(A,K1b2,B,K1b2)Fig.3Sedimentarysequenceofbraidedstreamfacies,,,,,,,,,,,25cm,,,,8.0m,,,,,,,,,,,,,,,,10%35%,,,34cm,,,,,,,,1:39,,,,,(4)4Fig.4Sedimentarysequenceoffan-deltafacies2.4,,,,,,,,,,,,,,,,,,,,,,,,:I:,,,,,,,,II:,,,,III:,,,,:(1):,405,23cm,78cm,,,60%70%,,(2):,,70%,,,(3):,,,,40%,,(4):,,,,,,,,,,,,,5Fig.5SketchmapofsedimentarycycleofLowerCretaceousinYingenBasin3,,,,(5)3.1,,,,,,,,:,3.2,,,1:41,,,,,;,,();,();()3.3,,,,,,,,,,,[6],,,,4,:(1),,,(2),,(3),,,,,,,;,;,,,![1].().:,1989[2]..:,1991425[3]..,1984,4(4):127[4],..:,1992[5],..:,1999[6],,..,1999,19(1):2428[7],..,2001,3(1):2534SEDIMENTARYFACIESOFTHELOWERCRETACEOUSOFYINGENBASINININNERMONGOLIAWuShaobo1,2BaiYubao2YangYouyun21DepartmentofGeology,NorthwestUniversity,Xian710069,Shanxi2DepartmentofResourcesandEnvironmentEngineering,XianPetroleumInstitute,Xian710065,ShanxiAbstractThetypesofsedimentaryfaciesoftheLowerCretaceousandtheirdistributionandevo2lutioninYingenBasinareanalyzedaccordingtodetailedsurveyandanalysisonalotoffieldgeologicalsectionsaroundthebasin.ThesedimentsoftheLowerCretaceousinYingenBasinarethetypicalinte2riorlacustrinebasindeposits,andtheredevelopedthesandstone,conglomerate,mudstone,carbonaterocksover2000meters,withneutraltobasicvolcanicrocksandalittleoilshaleandevaporites.Thetypesofsedimentaryfaciesincludethealluvialfan,stream(mainlybraidedstream,fan-delta,deltaandlacustrinefacies).Theregionalstructuralmovementsmainlycontrolledthesedimentarysystemsandtheirdistributionandevolution.Thesedimentaryfaciesevolutioncanbeapproximatelydividedintothreestageswhichreflectsafullsedimentarycycleofafaultbasinfromformationanddevelopmenttoshrinkage.TheearlyphaseoftheEarlyCretaceouswasaninitialfaultdepressionstageofthebasin,andthemiddlephaseoftheEarlyCretaceouswasanintensefaultdepressionstageandthelatephaseoftheEarlyCretaceouswasafaultdepressionshrinkagestage.Eachstagedevelopedthespecificsedi2mentaryfaciesandfaciesassemblageindifferentpositionsofthebasin.Keywordssedimentaryfacies,LowerCretaceous,BayingebiFormation,YingenBasin,InnerMongoliaAboutthefirstauthorWuShaobo,bornin1965,graduatedfromLanzhouInstituteofGeology,ChineseAcademyofSciencesin1989.NowheisanassociateprofessorofXianPetroleumInstituteandisacandidateforthedoctordegreeattheDepartmentofGeologyinNorthwestUniversity.Hisre2searchinterestsincludesedimentology,reservoirgeologyandpetroleumgeology.1:43