大三啦-地史学第七章早古生代

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PartIIIGeologicHistorythe

(12学时 Chapter7GeologicHistoryofEarlyPaleozoicSubdivisionofEarlyPaleozoic&ItsTheCambrianofTheOrdovicianofTheSilurianofSubdivisionofEarlyPaleozoicandItsPeriodsandCambriannamedbyR.A.(1835)；broadsenseattheSiluriannamedbyRIMurchison1835，partlyoverlappedwithOrdoviciannamedbyC.(1879);fortheoverlappedUntil1960,Oformallyacceptedon21stIGC；then3subdivisionofPz1Namesadoptedfrom3ancienttribesinWales.IUGS-ISC,MajorFeaturesoftheEarlyBiota:海生无脊椎动物繁盛；始现脊椎动物和陆生植具壳生物始于Z末，Cam生物大爆发，蓬勃发展，生态分异，分区脊椎动物Cam出现，无颌类在O1发展，S2O3晚期生物集群绝灭；显生宙五大集群绝灭之一；成 Sedimentation：CaCO3成为碳酸盐主要组分；生物成岩作造礁生物，古杯MgCO3+CaCO3，与PreCam形成鲜明对比；气候分异，O2含量出现明显的气候分积LithosphericEvolution:Rodinia离散,分为5大陆；海平面3升3Rodinia在Pt3晚期裂解，Pz1离散期，5个大陆；O1海侵最大、欧洲、西伯利海侵广泛S末出现全球性海退与造山Paleozoic MarineInvertebratesandCambrian三叶虫(trilobites)：significantinCam，mostlybenthos；球接子类（笔石类：树形笔石类；双ajortoolsorlobalcorreai；鹦鹉螺类(nautiloids)：直角石类，游泳；O壳相的重要分子 腕足类(brachiopods)：底栖，壳相；Cam无铰纲；O具铰类月、正形类；S珊瑚类(corals)：benthic，reeffacies；床板类，四射类；单体、复体；mostlyextinctatterminalCam.；小壳类(small yfossils)：earliest yfossils；分类不明牙形类(conodonts)：Cam2晚期始出现，O极丰富；单锥型；全球对的主要依据；副牙形-澄江动物群(Chenjiangfauna)：Cam1，520Ma,morethanBurgessShaleFauna：Cam2早期，多门类;凱里动物群(Kaili略晚PaleozoicMarineInvertebratesandCambrianBiotic现，无颌类在O1Small yfossilsfrombasalCambrianE 展，S2见于淡水； Diversifiedsmall yfossilsfrombasalMeishucunian,lowerCambrian,EasternEvolutionofProto-TethysinEarlyPaleozoicOrogenicbeltformedinlateSilurian(N.AmericanandEuropeanMajorFeaturesoftheEarlyBiota:海生无脊椎动物繁盛；始现脊椎动物和陆生植具壳生物始于Z末，Cam生物大爆发，蓬勃发展，生态分异，分区脊椎动物Cam出现，无颌类在O1发展，S2O3晚期生物集群绝灭；显生宙五大集群绝灭之一；成 Sedimentation：CaCO3成为碳酸盐主要组分；生物成岩作造礁生物，古杯MgCO3+CaCO3，与PreCam形成鲜明对比；气候分异，O2含量出现明显的气候分积LithosphericEvolution:Rodinia离散,分为5大陆；海平面3升3Rodinia在Pt3晚期裂解，Pz1离散期，5个大陆；O1海侵最大、欧洲、西伯利海侵广泛S末出现全球性海退与造山EarlyPaleozoic OccurrenceandDevelopmentofEarliestvertebrates－Cam1澄江动物群中，出现有头索（云 见于O2，星甲鱼(Astrapis)网甲鱼(Arandaspis);S大量繁OutlineofPlants’植物；poorlyS2出现蕨类高等植物；滨海

Bio-faciesandBiogeographic isolation)造成的生物演化谱系(bioticevolutionarylineage)的差O出现笔石页岩相与壳灰岩相；Cam—planktonic&benthicPacificRealm，东方动物AtlanticRealm，西方动物群MixedRealm(混生区)，中间动物群同；据笔石分为Pacific,Atlantic和mixedrea Olenellus–Atlantic Redlichia–Pacific

EarlyCambrianBiogeographic(Hist.Geol.Text-book,GeologicaleventsinSiluriantoTheCambrianofCambrianofChinacanbesummarizedastwoStableType：华北(NC)板块、扬子(YT)板块主体及塔里木(TR)板块北缘；dominatedbycarbonates,withabundantfossils，especiallybenthictrilobites.MobileType：mainlyalongcontinentalmarginsofthethreeplates；inshelfmargin-slopeareas,dominatedbycarbonaceous,siliceousandthin-beddedlimestone&argillaceoussediments，bearingpelagictrilobites；whileinabyssalareasdominatedbyvolcanicsandargillaceousflyschsediments,rarefossils。CambriansedimentarytypesofYangtze扬子区-稳定沉积类型(Epicontinent江南区 东南区-复杂岛海活动型(AC

三区两TheCambrianonYangtzeCam2-3－dominatedbycarbonates,withrareCam1－dominatedbymud-sandcarbonates，withabundantKunmingSection,E. 794m梅树村组：磷块岩+粘土岩，小壳+筇竹寺组：页-粉砂+砂-虫；底磷结核+海绿石沧浪铺组：页+砂，交错层理+龙王庙组：白云岩+粉-陡坡寺组：下砂-双龙潭组：灰-泥灰+砂-页岩Cam3缺失，上 Transversefacieschangeand扬子区整体上是西高东低、差异不大的epeiricsea；Cam1,silisiclasticsdominant,withlimestone,changedupwardintocarbonatesabundantfossils；Cam2-3,岩性分异不明显，mainlydolomite,dolomiticfossilesSketchmapshowingCambriansedimentationonYangtzeplate(Hist.Geol.Text-TheCambrianonNorthChina absenceinCam1sediments,otherpartsdominatedbyshallowwatercarbonates，fossilspoliferous；typicalEpeiricseaenvironments.ZhangxiaSection,

馒头组：紫-黄钙质shale+藻纹marls；底页岩+硅质灰岩毛庄组：紫红shale徐庄组：紫灰、黄绿shls张夏组：鲕-藻灰岩 崮山组：薄层灰岩、页岩+竹叶岩长山少量TransverseFaciesChangeand1NC在CAM.总体N高S低的陆表海。CAM1-2全区1CAM13从南侧秦岭洋向北海侵，到达各地的时间不同，故地层发育不CNCAM3南部相对抬升，变浅，形成自南向北穿时的潮坪相三山云岩；北部燕辽地区相对下降，为浅海灰岩。形成南高北低地理局 局华北板块寒武系沉积示意剖面图(据地史 CambrianSubdivisionandcorrelationofChina(afterShiTheOrdovicianofInChinaOrdoviciansedimentswidespread,withvarioustarytypesandabundantfossils,typicalfortheStable华北、塔里木和喜马拉雅-滇西地dominatedbycarbonates,Swimmingnautiloids，benthictrilobites、gastropodsanddendritic扬子板块(YZ)carbonatesandargillaceoussediments Mobile华北板西缘、扬子东南缘-PCM，characterizedbyflyschandpara-flyschvolcanic-clasticsediments，withargillaceous,silisiceous&carbonates;biota-graptolites,withsomeswimmingandbenthics yfossilsTheOrdovicianonYangtze区，其沉积与生物面YichangSection,西陵峡组：砾屑灰岩-南津关组：砾-鲕，潮间-O1分乡组：鲕-泥-红花园组：厚层生屑灰 •大湾组：骨屑亮晶 •牯牛潭组：泥质灰岩 •庙坡组：黑色页岩为宝塔组：泥晶灰 •临湘组：瘤状灰岩五峰组：笔石页 Hirnantia TansverseFaciesChangeandYZ总体西部多silisclastics，东部多O1海侵向西onlap，川西-滇东形成具交错层理砂页岩(滨岸)。向源碎屑减少，黔北-川南砂泥+碳酸盐岩，鄂西碳酸盐+泥质酸盐O2滇黔古陆形成，碳酸盐岩为滞流盆地沉积。O3早期海侵广，晚期古陆扩大，滞流，构造SketchshowingOrdoviciansedimentationinSouthChina(HistGeolText-TheOrdovicianonNCInNCP,theOmainlylimestone&dolomite,locallysomesilts，litho-faciesstable;O1complete,O2-pleteonlyinafewofareasTangshanSection,TransverseFaciesChangeandO1部。O1晚期新海侵，北阉庄组向S、NW区北阉庄组上超于治里组或CAMO1末-O2岩相稳定，海侵广泛。O3为长期剥蚀的古 OrdovicianSubdivisionandcorrelationofChina(afterShiTheSilurianof些地区发生subductioncollisionandorogeny.Crustalmovementsactiveglobaltectonicframe&paleogeography.成南、北两块。板块内部因受板缘造山运动的影响，总体上，SCS发育较好，以碎屑岩为主。NC区没有沉积，是风化侵蚀的古陆，边缘地带发育碎屑 TheSilurianonYangtzeSfollowsthepaleogeographicoutlineofO3S1-2海侵限于YichangSection：仅S1- 2)QujinSection：仅S2-

上扬子－TransverseFaciesChangeand总体上以碎屑岩为主。宜昌向SE沿江南古陆北侧至修水，S完整，S1石相细碎屑岩；S2壳相碎屑岩；S3陆相碎屑岩，厚度巨大长江中下游一带，与华夏陆块向扬子仰SW陆上升影响成为剥蚀区表明随江南古陆上升前陆盆地向NW陆上升影响成为剥蚀区表明随江南古陆上升前陆盆地向NWSketchshowingSiluriansedimentationonYangtzeplate(HistGeol.,Tect-book,SilurianonNorthChina