Full-Text Search:
Home|About CNKI|User Service|中文
Add to Favorite Get Latest Update

Conodont Fauna and Sedimentary Environment of Wuchiapingian of Upper Permian in Shizhu Area,Chongqing

YANG Bao-zhong,ZHANG Ning,XIA Wen-chen(Faculty of Earth Sciences,China University of Geosciences,Wuhan 430074,China)  
The Wuchiapingian of Upper Permian in the Lengshuixi section in Shizhu,Chongqing,is composed of siltstone,mudstone and limestone(including dolomite),with intercalations of chert beds and shale.Based on the study of conodont biostratigraphy,the limestone was divided into 2 members.The lower member is composed of mudstone,wackestone and dolomite(lack in conodonts),while the upper member is comprised of mudstone and wackestone,with a little dolomite(abundance conodonts).Eleven species conodonts have been discovered,Clarkina guangyuanensis,C.orientalis、C.liangshanensis、C.bizarrensis、C.longicuspidata、C.inflect、C.renewalpostbitteri、C.protowangi、C.n.sp.A、C.n.sp.B and C.n.sp.C,some of whom are new species,as C.renewalpostbitteri、C.protowangi、C.n.sp.A、C.n.sp.B and C.n.sp.C.The isotope analysis of carbon and oxygen shows that: the isotope values changed frequently in the lower member(lack in conodonts) while that changes less in the upper limestone member(rich in condonts).The result reflects that the sedimentary environment has changed obviously.The lower member belongs to the alongshore circumstance where the salinity of sea water was abnormal due to the mixture of freshwater and the conodont growth was restricted.The upper member belongs to the normal shallow sea environment,where the conodonts grew well and abundant.Wuchiapingian can be subdivided into the Upper Wuchiaping substage and the Lower Wuchiapingian substage according to the first occurrence of C.renewalpostbitteri.
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©CNKI All Rights Reserved