An analysis of Ordovician graptolite diversity across several distinct lithofacies belts in South China,which represent nearshore,inner-shelf,outer-shelf,slope,and basin environments,indicates that diversity increases...An analysis of Ordovician graptolite diversity across several distinct lithofacies belts in South China,which represent nearshore,inner-shelf,outer-shelf,slope,and basin environments,indicates that diversity increases progressively from nearshore toward the outer-shelf,acquiring its maximum in the slope facies and thereafter decreases slightly in basinal facies.When scaled against graptolite zones and more equal duration 'Time Units',the graptolite diversity patterns of the Early and Middle Ordovician are broadly similar among the distinct environments of South China but exhibit some important differences.A synthesized graptolite diversity curve from the Early Ordovician to the Sandbian Stage of the Late Ordovician in South China displays a step-wise increase with three peaks:1) middle Floian(Early Ordovician),2) late Dapingian-early Darriwilian(Middle Ordovician),and 3) latest Darriwilian(Middle Ordovician),which closely coincide with transgressive events in South China,implying a likely correlation.The biogeographic distribution of four graptolites with different ecological preferences,Pseudisograptus,Isograptus-Parisograptus,Undulograptus austrodentatus,and Corymbograptus turgidus,displays a significant parallelism with the coast or shelf margin,suggesting that their distributions may be controlled by water depth,basin morphology,and the distance from the coast.展开更多
回顾近年来所发现的与我国三叶虫有关的11个晚出同名属及其替代名的研究现状,详细报导最近新发现的37个晚出同名三叶虫属中的13个属及其替代名。这些属涉及到寒武纪,奧陶纪,志留纪和泥盆纪的三叶虫。此外,河南龙Honania Young,1979(模式...回顾近年来所发现的与我国三叶虫有关的11个晚出同名属及其替代名的研究现状,详细报导最近新发现的37个晚出同名三叶虫属中的13个属及其替代名。这些属涉及到寒武纪,奧陶纪,志留纪和泥盆纪的三叶虫。此外,河南龙Honania Young,1979(模式种H.complicidentata Young,1979)是产于河南济源晚二叠世爬行类锯齿龙科的一个属,由于晚于三叶虫河南虫HonaniaLee in Luet al.,1963(模式种H.lata Lee in Luet al.,1963)所建,成为无效属名,建议将河南龙的属名更名为钟键龙(新属)Zhongjiania gen.nov.。展开更多
基金supported by Ministry of Science and Technology of China (Grant Nos. 2006CB806402, 2006FY120300-4,2008ZX05008-001-001)National Natural Science Foundation of China (Grant No. 40532009)
文摘An analysis of Ordovician graptolite diversity across several distinct lithofacies belts in South China,which represent nearshore,inner-shelf,outer-shelf,slope,and basin environments,indicates that diversity increases progressively from nearshore toward the outer-shelf,acquiring its maximum in the slope facies and thereafter decreases slightly in basinal facies.When scaled against graptolite zones and more equal duration 'Time Units',the graptolite diversity patterns of the Early and Middle Ordovician are broadly similar among the distinct environments of South China but exhibit some important differences.A synthesized graptolite diversity curve from the Early Ordovician to the Sandbian Stage of the Late Ordovician in South China displays a step-wise increase with three peaks:1) middle Floian(Early Ordovician),2) late Dapingian-early Darriwilian(Middle Ordovician),and 3) latest Darriwilian(Middle Ordovician),which closely coincide with transgressive events in South China,implying a likely correlation.The biogeographic distribution of four graptolites with different ecological preferences,Pseudisograptus,Isograptus-Parisograptus,Undulograptus austrodentatus,and Corymbograptus turgidus,displays a significant parallelism with the coast or shelf margin,suggesting that their distributions may be controlled by water depth,basin morphology,and the distance from the coast.
文摘回顾近年来所发现的与我国三叶虫有关的11个晚出同名属及其替代名的研究现状,详细报导最近新发现的37个晚出同名三叶虫属中的13个属及其替代名。这些属涉及到寒武纪,奧陶纪,志留纪和泥盆纪的三叶虫。此外,河南龙Honania Young,1979(模式种H.complicidentata Young,1979)是产于河南济源晚二叠世爬行类锯齿龙科的一个属,由于晚于三叶虫河南虫HonaniaLee in Luet al.,1963(模式种H.lata Lee in Luet al.,1963)所建,成为无效属名,建议将河南龙的属名更名为钟键龙(新属)Zhongjiania gen.nov.。