苏北坳陷泰州组微古生物组合及其石油地层学意义

THE MICROPALEONTOLOGY ASSEMBLAGE OF TAIZHOU FORMATION, NORTHERN JIANGSU DEPRESSION, AND ITS SIGNIFICANCE TO PETROLEUM STRATIGRAPHY

李哲 张锡南

Li Zhe Zhang Xinan

地质矿产部石油地质中心实验室

Central Laboratory of Petroleum Geology, Ministry of Geology and Mineral Resources

泰州组露头仅零星见于仪征县小河口地区,广大苏北坳陷内据钻井揭示,除建湖隆起及其它个别地区外,一般均有分布,厚度在30—300米间,最厚达400米。并可划分为两个岩性段,即上部泥岩段和下部砂岩段。其岩性除金湖凹陷和高邮凹陷西北部,以咖啡色、棕灰色、紫红色等一红到底的杂色砂泥岩互层,上下分层不明显外,其它各区的上部泥岩段则多以灰黑色泥岩为主,局部地区在其顶部有厚度不等的杂色泥岩、砂泥岩层;下部砂岩段,以棕灰色、浅灰至灰白色粉砂岩、细砂岩为主,夹少量灰紫色或灰黑色粉砂质泥岩,底部常有厚度不等的砂砾岩或砾岩存在。

Northern Jiangsu Depression is a fault-down basin of 32,000 km2 located in the second uplifted belt of NNE trending-Neocathaysian tectonic system. Sediments have been deposited since Paleozoic, of which the Tertiary is especially important for oil. This paper consists of three parts. l.The sporo-pollen and ostracoda assemblages in Taizhou Formation of the early, middle Paleocene and its time attribution are outlined. 2.In the light of the features of sporo-pollen and ostracoda. assemblages, the palaeoclimate, palaeovegetation and palaeogeography environments of deposition period of Taizhou Formation are discussed. 3.By using the distribution, taphonomy, differentiation, evolution and type characteristics of sporo-pollen and ostracoda fossils, the relationship between the environment of deposition period of Taizhou Formation and the source rock sequences are expounded.

https://doi.org/10.11781/sysydz198504313