摘要
新疆塔中地区奥陶系分布广泛。主要根据化石、岩性特征、对比等将研究区内奥陶系划分为三统四组:下奥陶统蓬莱坝组与下伏上寒武统丘里塔格下亚群呈假整合接触,鹰山组归为中下奥陶统,一间房组划为中奥陶统,良里塔格组划归上奥陶统。良里塔格组可细分为3个岩性段,鹰山组可划分为4个岩性段。良里塔格组与鹰山组之间存在区域地层缺失和不整合,桑塔木组与上覆地层呈不整合接触,与下伏良里塔格组由于所处的位置不同呈整合或不整合接触。
Ordovician strata are widely distributed in the Tazhong Area. The goal of study is to identify the Cambrian-Ordovician boundary in this area and to determine the age and lithostratigraphic relationship among the Yingshan, Yijianfang, and Lianglitage formations, on the basis of biostratigraphic and lithostratigraphic evidence. Research results are as follows： 1） The Yingshan Formation is regarded as Lower- Middle Ordovician, the Yijianfang Formation as Middle Ordovician, and the Lianglitage Formation as Upper Ordovician. 2） On the basis of lithostratigraphic data, the Ordovician System in this area is divided into three series and four formations. The Lianglitage Formation is further subdivided into three lithostrati- graphic units, and the Yingshan Formation is divided into four lithostratigraphic units. 3） The spatial distribution of the Lianglitage and Yingshan formations is characterized. An unconformity is identified between these two formations. 4） The contact between the Lower Ordovician Penglaiba Formation and the Upper Cambrian Qiulitager Formation is a disconformity. 5） The Sangtamu Formation is separated from the overlying strata by an angular unconformity, and the contact between the Sangtamu Formation and the underlying Lianglitage Formation is conformable at some sections but disconformable at others.
出处
《地层学杂志》
CSCD
北大核心
2009年第2期217-224,共8页
Journal of Stratigraphy
关键词
地层划分
鹰山组
蓬莱坝组
良里塔格组
桑塔木组
奥陶系
塔里木盆地
新疆
Ordovician System, Yingshan Formation, Penglaiba Formation, Lianglitage Formation, Sangtamu Formation,Tarim Basin, Xinjiang
