藏北班戈地区早白垩世欧特里夫期菊石的发现及其对下白垩统地层对比的约束  

The discovery of Early Cretaceous Hauterivian Ammonite Fauna in Bange area,northern Tibet and its constraints on the stratigraphic correlation of the Lower Cretaceous

作　　者：王东[1,2] 赵安坤 万友利[1,2] 宋春彦 曾胜强[1,2] 李学仁 WANG Dong;ZHAO Ankun;WAN Youli;SONG Chunyan;ZENG Shengqiang;LI Xueren(Chengdu Center,China Geological Survey,Chengdu 610081,Sichuan,China;Key Laboratory for Sedimentary Basin and Oil and Gas Resources,MNR,Chengdu 610081,Sichuan,China)

机构地区：[1]中国地质调查局成都地质调查中心,四川成都610081 [2]自然资源部沉积盆地与油气资源重点实验室,四川成都610081

出　　处：《地质通报》2022年第10期1720-1727,共8页Geological Bulletin of China

基　　金：中国地质调查局项目《西南重要盆地多能源资源地质调查》(编号:DD20221661);国家自然科学基金项目《白云石化过程中孔隙形成与保存机制研究——以南羌塘坳陷布曲组白云岩为例》(批准号:41902138)。

摘　　要：在藏北班戈地区多尼组中发现了早白垩世欧特里夫期菊石。这些菊石化石部分保存较完整,鉴定出2科和1种(比较种),包括多皱菊石科Polyptychitidae,新考米菊石科Neocomitidae,减退菊石比较种Lyticoceras cf.stevrecensis。对比发现,该化石组合可能具有较强的地方属性特征。其中,Lyticoceras cf.stevrecensis属于地方菊石亚科,是早欧特里夫期的典型分子,可以与特提斯域的喜马拉雅北部、巴基斯坦北部和西地中海等地区的菊石进行对比,填补了班戈地区Thurmanniceras-Sarasinella菊石组合的欧特里夫期空白,这对于该地区的下白垩统地层对比和重新认识措勤盆地的沉积构造演化可能具有重要的约束作用和指示意义。Recently,ammonites have been discovered in the Bange area of northern Tibet,which of the age is Early Cretaceous Hauterivian.The ammonite assemblages sampled in the Duoni Formation are of good preservation.Two families and one comparative species have been identified,including Polyptychitidae,Neocomitidae,Lyticoceras cf.Stevrecensis.By comparison and analysis with early studies,the ammonites have strong local attribute characteristics.Lyticoceras cf.stevrecensis is the typical species of the Early Hauterivian,which belongs to the subfamily Endemoceratinae,and can be compared with those faunas from the Northern Himalayas,Northern Pakistan and Western Mediterranean(South-East France)around the Tethys realm,even the North-Eastern Peri-Tethys.The discovery of ammonites extends the epoch of Thurmanniceras-Sarasinella to Early Hauterivian.These findings could be important foundations for the stratigraphic correlation study of the Lower Cretaceous,and for re-recognizing the sedimentary tectonic evolution in this area of Cuoqin Basin.

关 键 词：菊石 欧特里夫期 早白垩世 班戈地区 措勤盆地 地质调查工程 西藏 

分 类 号：P534.53[天文地球—古生物学与地层学] Q915.818.4[天文地球—地质学]