东海盆地古近系地层划分与对比  

LITHOSTRATIGRAPHIC DIVISION AND CORRELATION OF THE PALEOGENE IN THE EAST CHINA SEA BASIN

作　　者：张迎朝 蒋一鸣 邹玮 祝幼华[2] 徐振中 李宁 唐贤君 张涛 ZHANG Ying Zhao;JIANG Yi Ming;ZOU Wei;ZHU You Hua;XU Zhen Zhong;LI Ning;TANG Xian Jun;ZHANG Tao(CNOOC China Limited,Shanghai Branch,Shanghai 200335;Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008)

机构地区：[1]中海石油(中国)有限公司上海分公司,上海200335 [2]中国科学院南京地质古生物研究所,江苏南京210008

出　　处：《地层学杂志》2024年第4期341-359,共19页Journal of Stratigraphy

基　　金：中海石油(中国)有限公司重大科技专项项目课题1(KJZX-2023-0101)资助。

摘　　要：东海盆地东部坳陷带西湖凹陷、西部坳陷带丽水—椒江凹陷是重要的油气探区,其主要烃源岩和储层多分布于古近系。受构造演化和沉积环境差异影响,古近纪时期不同阶段盆地东、西部坳陷带地层岩性组合及古生物面貌存在较大的差异,给区域地层划分和对比带来较大困难。本文基于东海盆地地层岩性、古生物、火山岩测年及地震勘探等方面的资料开展古近系研究:(1)建立了东海盆地东、西部坳陷带古近系对比关系,明确了地层序列东西差异分布的规律;(2)厘定了东海盆地西早东晚的“同序异时”效应和中央隆起带内北强南弱的“构造—沉积”分异作用是影响地层序列差异的主要控制因素;(3)进一步揭示了古近纪太平洋板块俯冲后撤与东海盆地断陷迁移、沉积充填的响应关系。该成果丰富了我国海域古近系研究,也为东海盆地石油地质条件及区带优选奠定了重要的研究基础。The eastern depression belt(represented by the Xihu Sag)and the western depression belt(represented by the Lishui-Jiaojiang Sag)of the East China Sea Basin are important oil-gas exploration districts in maritime China,and the main source rocks and reservoirs are mostly distributed in the Paleogene.Differences in tectonic evolution and sedimentary environment in different stages of the Paleogene between the two belts created large differences in lithology,paleontology,and seismology,which brings great difficulties in the basin-wide stratigraphic correlation.By integrating lithological,paleontological,and volcanic rock U-Pb dating data,revealed from drilling and seismic exploration in the basin,a comprehensive correlation of the Paleogene between the eastern and western depressions was established.The effects of“same sequence but different time”,i.e.,earlier in the western and later in the eastern parts of the East China Sea Basin,and the tectono-sedimentary differentiation,i.e.,stronger in the northern and weaker in the southern parts of the central uplift belt,are responsible for the stratigraphic differences.In addition,the fault depression shifting and basin filling in the East China Sea Basin reflects the subduction and retreat of the paleo-Pacific Plate.These achievements shall enrich the study of the Paleogene in maritime China,and lays a solid ground for the petroleum geological exploration and favorable areas selection in the East China Sea Basin.

关 键 词：东海盆地 古近系 岩石地层 古生物组合 沉积环境 

分 类 号：P534.61[天文地球—古生物学与地层学]