About This Item
This article has been peer-reviewed and accepted for publication in a future issue of the AAPG Bulletin. This abstract and associated PDF document are based on the authors' accepted "as is" manuscript.
Editorial Policy for Ahead of Print
- Full TextFull Text(subscription required)
- Pay-Per-View PurchasePay-Per-View
Purchase Options Explain
Cite This Item
Share This Item
The AAPG/Datapages Combined Publications Database
AAPG Bulletin
Ahead of Print Abstract
AAPG Bulletin, Preliminary version published online
Copyright © 2025. The American Association of Petroleum Geologists. All rights reserved.
DOI:10.1306/10212523056
Origin and source of natural 
gas
in the Upper Paleozoic in the Southwest of the Ordos Basin, China
gas in the Upper Paleozoic in the Southwest of the Ordos Basin, ChinaKaixuan Liu123 , Jianfa Chen12 , Rao Fu12 , Cong Chen12 , Zeya Chen4 , Shizhen Tao4 , Xinshe Liu3 , and Tuan Gu5
1 State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China
2 College of Geosciences, China University of Petroleum, Beijing 102249, China
3 PetroChina Changqing Oilfield Company, Xi’an, Shaanxi 710018, China
4 Research Institute of Petroleum Exploration and Development, PetroChina, Beijing 100083, China
5 PetroChina Liaohe Oilfield Company, Panjin, Liaoning 124010, China
Ahead of Print Abstract
gas field in the southwestern Ordos Basin, following over 50 years of petroleum exploration, has generated significant scientific interest in its origins, gas-generation mechanisms, and sources. This paper delves into gas genetic type, thermal maturity, source and the influence of secondary alteration by analyzing the geochemical characteristics of the gas and comparing it with tight sandstone gas found in other parts of the Ordos Basin. The study reveals that the natural gas in the Qingyang gas field is dry. When compared to the Sulige and Dongsheng gas fields, the δ13C and δD of methane are relatively heavier, while the δ13CC2+ (ethane, propane, etc.) are lighter. This suggests that the thermal maturity of the gas in this region is relatively high. The high thermal maturity is attributed to the over-mature thermal cracking of a Permian coal measure source rock. Additionally, the gas contains components from the primary cracking of an Ordovician source rock and the secondary cracking of oil from a Cambrian source rock. This mixing of different gas sources contributes to the unique geochemical characteristics of the gas in the southwestern Ordos Basin. Specifically, the lighter carbon isotope value of heavy hydrocarbons in the gas can be explained by the mixing of sapropelic kerogen-cracking gas and oil-cracking gas, which are rich in 12C. This study further substantiates the validity of multiple marine hydrocarbon source rocks in the Lower Paleozoic of the Ordos Basin, offering significant insights and guidance for future natural gas exploration endeavors.
Pay-Per-View Purchase Options
The article is available through a document delivery service. Explain these Purchase Options.
| Watermarked PDF Document: $16 | |
| Open PDF Document: $28 |
AAPG Member?
Please login with your Member username and password.
Members of AAPG receive access to the full AAPG Bulletin Archives as part of their membership. For more information, contact the AAPG Membership Department at [email protected].
