摘要
通过对新发现于新疆塔里木盆地西部上白垩统乌依塔克组有孔虫化石的时代分析,认为该组的时限为晚上伦期—赛诺期,综合分析各类化石的时代特征,本区土伦阶和赛诺阶的界线应划在Migros-Ammobaculites组合和Pararotalia-Nonionella组合之间。
The Upper Cretaceous Yingjisha Group in the western Tarim Basin is represented mainly by sediments of littoral, near-shore neritic dacies and subdivided ascendingly into the Kukebai Formation, Wuytak Formation and Ygezya Formations. Previously, foraminiferal fossils of Upper Cretaceous age were found from the Kukebai Formation. Recently, many well-preserved new forms were found in the Wuytak Formation overlying the Kukebai Formation. Four foraminiferal assemblages in the Wuytak Formation have been recognized in ascending order: the Migros-Ammobaculites Assemblage, the Pararotalia-Nonionella Assemblage, the Cibicidina-Quinqueloculina Assemblage, the Quinqueloculina-Massilina Assemblage. As a result, the age of the Wuytak Formations is assigned from Late Turonian to Senonian according to charateristics of foraminiferal assemblages. Therefrom, the Turonian-Senonian boundary would be placed between the Migros-Ammobaculites Assemblage and the Pararotailia-Nonionella Assemblage.
出处
《地层学杂志》
CSCD
北大核心
1995年第3期208-213,T001,共7页
Journal of Stratigraphy
关键词
有孔虫
地层
乌依塔克组
古动物
新疆
白垩纪
foraminifer
stratigraphy
Wuytak Formation
Turonian-Senonian boundary
Xinjing