首页|Characteristics and origin of low-organic-matter carbonate source rocks in the Middle-Upper Ordovician,Tarim Basin,northwestern China

Characteristics and origin of low-organic-matter carbonate source rocks in the Middle-Upper Ordovician,Tarim Basin,northwestern China

扫码查看
原文链接
  • NETL
  • NSTL
  • 万方数据
The continually-discovered large volumes of marine hydrocarbons indicate a huge exploration potential within the carbonate rocks of Ordovician in the Tarim Basin,northwestern China.The Middle-Upper Ordovician(O2+3)carbonate source rocks are at a highly mature stage.These rocks presently contain a low amount of total organic carbon(TOCpd<0.5％)(TOCpd means the present-day TOC).A mass balance approach is used to identify the source rocks that have expelled hydrocarbons.The characteristics and origin of hydro-carbon expulsion from low-TOCpd source rocks are studied,which are significant for oil exploration in the basin.The results showed that a low-TOCpd O2+3 source rock having expelled hydrocarbons was type Ⅰ and had a very narrow oil window.With a high rock maturity and a high original TOC(TOCo)value exceeding 1％,nearly 80％of the generated hydrocarbons were expelled.The content of gammacerane and C28 steranes in the oil and source rock extracts were relatively lean,with a V-shaped distribution of regular steranes,suggesting a possible genetic relation between the low-TOCpd source rocks and the marine oil in the Tabei area.Hydrogen-rich planktonic algae or acritarchs were the main hydrocarbon parent materials,distributed in the subsiding platform-slope facies.Organic matter was preserved under reducing conditions,and source rocks were formed with a favorable kerogen type and a moderate hydrocarbon generation potential.This study illustrates the hydrocarbon expulsion of low TOCpd source rocks in northern Tarim Basin,which is greatly significant for analyzing the genesis of marine crude oil in Tarim Basin,and evaluating the distribution of marine source rocks.This research method is theoretically significant for oil and gas exploration in the same type of highly-mature carbonate paleobasins.

Carbonate source rockMass balance approachPresent-day TOCGenesis mechanismTarim Basin

Jun-Qing Chen、Fu-Jie Jiang、Xiong-Qi Pang、Hai-Jun Yang、Kan-Yuan Shi、Bo Pang、Hong Pang、Jian-Fa Chen、Zhuo-Heng Chen、Xin-Gang Zhang、Song Wu

展开 >

State Key Laboratory of Petroleum Resources and Engineering,China University of Petroleum(Beijing),Beijing 102249,China

Basic Research Center for Energy Interdisciplinary,College of Science,China University of Petroleum(Beijing),Beijing 102249,China

Beijing Key Laboratory of Optical Detection Technology for Oil and Gas,China University of Petroleum(Beijing),Beijing 102249,China

State Key Laboratory of Petroleum Resources and Engineering(China University of Petroleum(Beijing)),Beijing 102249,China

College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China

Research Institute of Petroleum Exploration and Development,PetroChina Tarim Oilfield Company,Korla 841000,Xinjiang Uygur Autonomous Region,China

Geological Survey of Canada,Natural Resources Canada,Calgary T2L 2A7,Canada

展开 >

Joint Funds of National Natural Science Foundation of ChinaCNPC Science and Technology Major Project of the Fourteenth Five-Year PlanScience Foundation of China University of Petroleum(Beijing)

U19B6003-02-042021DJ01012462022YXZZ007

2024

10.1016/j.jop.2024.04.002

古地理学报(英文版)

古地理学报(英文版)

影响因子：0.186
ISSN：
年,卷(期)：2024.13(3)