Evaluation of source rocks and prediction of oil and gas resources distribution in Baiyun Sag,Pearl River Mouth Basin,China  

作　　者：GAO Yangdong ZHU Weilin PENG Guangrong LONG Zulie WANG Xudong SHI Chuang CHEN Cong HUANG Yuping ZHANG Bo 

机构地区：[1]Exploration and Development Department of CNOOC China Limited,Beijing 100010,China [2]State Key Laboratory of Marine Geology,Tongji University,Shanghai 200092,China [3]Shenzhen Branch of CNOOC(China)Co.Ltd.,Shenzhen 518054,China [4]CNOOC Deepwater Development Limited,Shenzhen 518054,China

出　　处：《Petroleum Exploration and Development》2024年第5期1138-1150,共13页石油勘探与开发（英文版）

基　　金：Supported by the National Oil and Gas Resource Evaluation Project for the 14th Five Year Plan of the Ministry of Natural Resources(QGYQZYPJ2022-3);China National Offshore Oil Corporation"14th Five Year Plan"Major Science and Technology Project(KJGG2022-0103-03)。

摘　　要：By conducting organic geochemical analysis of the samples taken from the drilled wells in Baiyun Sag of Pearl River Mouth Basin,China,the development characteristics of hydrocarbon source rocks in the sag are clarified.Reconstruct the current geothermal field of the sag and restore the tectonic-thermal evolution process to predict the type,scale,and distribution of resources in Baiyun Sag through thermal pressure simulation experiments and numerical simulation.The Baiyun Sag is characterized by the development of Paleogene shallow lacustrine source rocks,which are deposited in a slightly oxidizing environment.The source rocks are mainly composed of terrestrial higher plants,with algae making a certain contribution,and are oil and gas source rocks.Current geothermal field of the sag was reconstructed,in which the range of geothermal gradients is(3.5–5.2)℃/100 m,showing an overall increasing trend from northwest to southeast,with significant differences in geothermal gradients across different sub-sags.Baiyun Sag has undergone two distinct periods of extensional process,the Eocene and Miocene,since the Cenozoic era.These two periods of heating and warming events have been identified,accelerating the maturation and evolution of source rocks.The main body of ancient basal heat flow value reached its highest at 13.82 Ma.The basin modelling results show that the maturity of source rocks is significantly higher in Baiyun main sub-sag than that in other sub-sags.The Eocene Wenchang Formation is currently in the stage of high maturity to over maturity,while the Eocene Enping Formation has reached the stage of maturity to high maturity.The rock thermal simulation experiment shows that the shallow lacustrine mudstone of the Wenchang Formation has a good potential of generating gas from kerogen cracking with high gas yield and long period of gas window.Shallow lacustrine mudstone of the Enping Formation has a good ability to generate light oil,and has ability to generate kerogen cracking gas in the late stage.The gas yie

关 键 词：Pearl River Mouth Basin Baiyun Sag PALEOGENE source rock evaluation tectonic-thermal evolution oil and gas resource potential 

分 类 号：TE34[石油与天然气工程—油气田开发工程] P618.13[天文地球—矿床学]