Discussion on high hydrocarbon generation efficiency of saline lacustrine source rocks with low TOC: A case study of the second member of Funing Formation, Qintong Sag, Subei Basin

Significant progress has been made in shale oil exploration within the second member of the Funing Formation in the Qintong Sag, Subei Basin. However, geologists have noted that the measured Total Organic Carbon(TOC) contents are generally below 2%. Despite this, it is believed that source rocks in...

Full description

Saved in:
Bibliographic Details
Main Author: GAO Yuqiao, HE Xipeng, CHENG Xiong, TANG Xuan, HUA Caixia, ZAN Ling, ZHANG Peixian, CHEN Xuewu, PANG Yiwei
Format: Article
Language:zho
Published: Editorial Department of Petroleum Reservoir Evaluation and Development 2024-10-01
Series:Youqicang pingjia yu kaifa
Subjects:
Online Access:https://red.magtech.org.cn/fileup/2095-1426/PDF/1728631282763-1336447362.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850232797382311936
author GAO Yuqiao, HE Xipeng, CHENG Xiong, TANG Xuan, HUA Caixia, ZAN Ling, ZHANG Peixian, CHEN Xuewu, PANG Yiwei
author_facet GAO Yuqiao, HE Xipeng, CHENG Xiong, TANG Xuan, HUA Caixia, ZAN Ling, ZHANG Peixian, CHEN Xuewu, PANG Yiwei
author_sort GAO Yuqiao, HE Xipeng, CHENG Xiong, TANG Xuan, HUA Caixia, ZAN Ling, ZHANG Peixian, CHEN Xuewu, PANG Yiwei
collection DOAJ
description Significant progress has been made in shale oil exploration within the second member of the Funing Formation in the Qintong Sag, Subei Basin. However, geologists have noted that the measured Total Organic Carbon(TOC) contents are generally below 2%. Despite this, it is believed that source rocks in saline lacustrine basins can generate substantial amounts of petroleum even with low organic matter abundance, a concept known as the “low TOC” and highly efficient hydrocarbon generation mode of saline lacustrine source rocks. As hydrocarbon generation and expulsion occur during thermal maturation, the TOC levels in source rocks decrease. Therefore, accurately restoring the original TOC of these source rocks is crucial for a proper understanding of their hydrocarbon generation capacity, as well as for evaluating petroleum resources and supporting reserve growth and production enhancement. This study focuses on the typical mudstones and shales of the second member of the Funing Formation in the Qintong Sag. Techniques such as hydrocarbon generation simulation experiments, rock pyrolysis data, TOC and productive carbon content evolution during thermal simulation, and an element mass conservation method were employed to restore the original TOC of these mudstones and shales. The findings reveal that the TOC recovery coefficient of these saline source rocks can exceed values between 3 to 4, and this coefficient is significantly influenced by the lithology. The study found that: the TOC recovery coefficient increases with thermal maturity, the coefficient for laminated shale is higher than that for massive mudstone, and the TOC recovery coefficients for mudstones in the Ⅳ sub-member and shales in the Ⅰ to Ⅲ sub-members of the second member of the Funing Formation range from 1.1~1.5 and 1.5~3.0, respectively. These variations are attributed to differences in the type of organic matter and the hydrocarbon generating activation energy, leading to a higher hydrocarbon transformation rate and TOC recovery coefficient in shales compared to mudstones.
format Article
id doaj-art-971f2c11ba4f4d3f85099d5507d3afc6
institution OA Journals
issn 2095-1426
language zho
publishDate 2024-10-01
publisher Editorial Department of Petroleum Reservoir Evaluation and Development
record_format Article
series Youqicang pingjia yu kaifa
spelling doaj-art-971f2c11ba4f4d3f85099d5507d3afc62025-08-20T02:03:05ZzhoEditorial Department of Petroleum Reservoir Evaluation and DevelopmentYouqicang pingjia yu kaifa2095-14262024-10-0114567868710.13809/j.cnki.cn32-1825/te.2024.05.002Discussion on high hydrocarbon generation efficiency of saline lacustrine source rocks with low TOC: A case study of the second member of Funing Formation, Qintong Sag, Subei BasinGAO Yuqiao, HE Xipeng, CHENG Xiong, TANG Xuan, HUA Caixia, ZAN Ling, ZHANG Peixian, CHEN Xuewu, PANG Yiwei01. Sinopec East China Oil & Gas Company, Nanjing, Jiangsu 210000, China;2. School of Energy Resource, China University of Geosciences(Beijing), Beijing 100083, ChinaSignificant progress has been made in shale oil exploration within the second member of the Funing Formation in the Qintong Sag, Subei Basin. However, geologists have noted that the measured Total Organic Carbon(TOC) contents are generally below 2%. Despite this, it is believed that source rocks in saline lacustrine basins can generate substantial amounts of petroleum even with low organic matter abundance, a concept known as the “low TOC” and highly efficient hydrocarbon generation mode of saline lacustrine source rocks. As hydrocarbon generation and expulsion occur during thermal maturation, the TOC levels in source rocks decrease. Therefore, accurately restoring the original TOC of these source rocks is crucial for a proper understanding of their hydrocarbon generation capacity, as well as for evaluating petroleum resources and supporting reserve growth and production enhancement. This study focuses on the typical mudstones and shales of the second member of the Funing Formation in the Qintong Sag. Techniques such as hydrocarbon generation simulation experiments, rock pyrolysis data, TOC and productive carbon content evolution during thermal simulation, and an element mass conservation method were employed to restore the original TOC of these mudstones and shales. The findings reveal that the TOC recovery coefficient of these saline source rocks can exceed values between 3 to 4, and this coefficient is significantly influenced by the lithology. The study found that: the TOC recovery coefficient increases with thermal maturity, the coefficient for laminated shale is higher than that for massive mudstone, and the TOC recovery coefficients for mudstones in the Ⅳ sub-member and shales in the Ⅰ to Ⅲ sub-members of the second member of the Funing Formation range from 1.1~1.5 and 1.5~3.0, respectively. These variations are attributed to differences in the type of organic matter and the hydrocarbon generating activation energy, leading to a higher hydrocarbon transformation rate and TOC recovery coefficient in shales compared to mudstones.https://red.magtech.org.cn/fileup/2095-1426/PDF/1728631282763-1336447362.pdf|low organic matter abundance|source rock|toc|recovery coefficient|the second member of funing formation
spellingShingle GAO Yuqiao, HE Xipeng, CHENG Xiong, TANG Xuan, HUA Caixia, ZAN Ling, ZHANG Peixian, CHEN Xuewu, PANG Yiwei
Discussion on high hydrocarbon generation efficiency of saline lacustrine source rocks with low TOC: A case study of the second member of Funing Formation, Qintong Sag, Subei Basin
Youqicang pingjia yu kaifa
|low organic matter abundance|source rock|toc|recovery coefficient|the second member of funing formation
title Discussion on high hydrocarbon generation efficiency of saline lacustrine source rocks with low TOC: A case study of the second member of Funing Formation, Qintong Sag, Subei Basin
title_full Discussion on high hydrocarbon generation efficiency of saline lacustrine source rocks with low TOC: A case study of the second member of Funing Formation, Qintong Sag, Subei Basin
title_fullStr Discussion on high hydrocarbon generation efficiency of saline lacustrine source rocks with low TOC: A case study of the second member of Funing Formation, Qintong Sag, Subei Basin
title_full_unstemmed Discussion on high hydrocarbon generation efficiency of saline lacustrine source rocks with low TOC: A case study of the second member of Funing Formation, Qintong Sag, Subei Basin
title_short Discussion on high hydrocarbon generation efficiency of saline lacustrine source rocks with low TOC: A case study of the second member of Funing Formation, Qintong Sag, Subei Basin
title_sort discussion on high hydrocarbon generation efficiency of saline lacustrine source rocks with low toc a case study of the second member of funing formation qintong sag subei basin
topic |low organic matter abundance|source rock|toc|recovery coefficient|the second member of funing formation
url https://red.magtech.org.cn/fileup/2095-1426/PDF/1728631282763-1336447362.pdf
work_keys_str_mv AT gaoyuqiaohexipengchengxiongtangxuanhuacaixiazanlingzhangpeixianchenxuewupangyiwei discussiononhighhydrocarbongenerationefficiencyofsalinelacustrinesourcerockswithlowtocacasestudyofthesecondmemberoffuningformationqintongsagsubeibasin