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 © 2024. The American Association of Petroleum Geologists. All rights reserved.
DOI:10.1306/07122423030
Igneous intrusion drives in-reservoir oil thermal cracking: Case from the Subei Basin, Eastern China
Ao Su123 , Honghan Chen1 , Yue-xing Feng34 , Jian-xin Zhao3 , and Qiang Liu5
1 China University of Geosciences (Wuhan), Hubei 430074, China
2 Yangtze University, Wuhan, Hubei 430100, China
3 Radiogenic Isotope Facility, School of Earth and Environmental Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
4 Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong 519080, China
5 Bureau of Geophysical Prospecting INC., China National Petroleum Corporation, Hebei 072750, China
Ahead of Print Abstract
phase
synchronous with silica diagenesis, and a later phase
occurring after silicification and carbonate cementation, and concurrently with fracturing. The older oil inclusions record the initial oils that served as precursors to the pyrobitumen, while the younger generation was likely formed during oil cracking. Fissure calcites containing primary oil inclusions yield a LA-MC-ICP-MS U-Pb age of 44.3 ± 1.5 Ma, coinciding with the published timing of volcanism. Homogenization temperatures from aqueous inclusions lie between 177.1 - 198.3 ℃, broadly consistent with clumped isotope temperature (195.5 ± 6.5 ℃) of fissure calcites and with bitumen Raman-derived temperatures (163.7 - 212.9 ℃). These observations suggest that rising temperatures that accompanied the mid-Eocene igneous intrusion resulted in the initial oils being in-situ thermally cracked into short-chain hydrocarbons and pyrobitumen. The resulting volumetric expansion, in conjunction with reduced permeability from pyrobitumen deposition, led to hard overpressures, consequent fracturing, and hydrocarbon leak-off.
Pay-Per-View Purchase Options
The article is available through a document delivery service. Explain these Purchase Options.
| Watermarked PDF Document: $14 | |
| Open PDF Document: $24 |
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].