A Caltech Library Service

Tracing of deeply-buried source rock: A case study of the WC9-2 petroleum pool in the Pearl River Mouth Basin, South China Sea

Xiao, X. M. and Li, N. X. and Gan, H. J. and Jin, Y. B. and Tian, H. and Huang, B. J. and Tang, Y. C. (2009) Tracing of deeply-buried source rock: A case study of the WC9-2 petroleum pool in the Pearl River Mouth Basin, South China Sea. Marine and Petroleum Geology, 26 (8). pp. 1365-1378. ISSN 0264-8172.

[img] PDF - Published Version
Restricted to Repository administrators only
See Usage Policy.


Use this Persistent URL to link to this item:


The identification of a deeply-buried petroleum-source rock, owing to the difficulty in sample collection, has become a difficult task for establishing its relationship with discovered petroleum pools and evaluating its exploration potential in a petroleum-bearing basin. This paper proposes an approach to trace a deeply-buried source rock. The essential points include: determination of the petroleum-charging time of a reservoir, reconstruction of the petroleum generation history of its possible source rocks, establishment of the spatial connection between the source rocks and the reservoir over its geological history, identification of its effective source rock and the petroleum system from source to trap, and evaluation of petroleum potential from the deeply-buried source rock. A case study of the W9-2 petroleum pool in the Wenchang A sag of the Pearl River Mouth Basin, South China Sea was conducted using this approach. The W9-2 reservoir produces condensate oil and gas, sourced from deeply-buried source rocks. The reservoir consists of a few sets of sandstone in the Zhuhai Formation, and the possible source rocks include an early Oligocene Enping Formation mudstone and a late Eocene Wenchang Formation mudstone, with a current burial depth from 5000 to 9000 m. The fluid inclusion data from the reservoir rock indicate the oil and the gas charged the reservoir about 18–3.5 Ma and after 4.5 Ma, respectively. The kinetic modeling results show that the main stages of oil generation of the Wenchang mudstone and the Enping mudstone occurred during 28–20 Ma and 20–12 Ma, respectively, and that the δ^(13)C_1 value of the gas generated from the Enping mudstone has a better match with that of the reservoir gas than the gas from the Wenchang mudstone. Results from a 2D basin modeling further indicate that the petroleum from the Enping mudstone migrated upward along the well-developed syn-sedimentary faults in the central area of the sag into the reservoir, but that the petroleum from the Wenchang mudstone migrated laterally first toward the marginal faults of the sag and then migrated upward along the faults into shallow strata. The present results suggest that the trap structure in the central area of the sag is a favorable place for the accumulation of the Enping mudstone-derived petroleum, and that the Wenchang mudstone-derived petroleum would have a contribution to the structures along the deep faults as well as in the uplifted area around the sag.

Item Type:Article
Related URLs:
URLURL TypeDescription
Additional Information:© 2009 Elsevier. Received 4 September 2008; revised 21 February 2009; accepted 25 February 2009; available online 6 March 2009. The authors are indebted to Dr. Andrew Hanson and two anonymous reviewers for their insightful comments and suggestions that have significantly improved the manuscript. This work was financially supported by the Natural Science Fund for Distinguished Young Scholars (Grant No. 40625011), the Key Project of Chinese Academy of Science (Grant No. KZCX2-YW-114) and the Earmarked Fund of the State Key Laboratory of Organic Geochemistry (Grant No. SKLOG2008A01). This is contribution No.IS1050 from GIGCAS.
Funding AgencyGrant Number
Natural Science Fund for Distinguished Young Scholars40625011
Key Project of Chinese Academy of ScienceKZCX2-YW-114
Earmarked Fund of the State Key Laboratory of Organic GeochemistrySKLOG2008A01
Subject Keywords:Deeply-buried source rock; Fluid inclusion; Kinetic modeling; 2D basin modeling; Wenchang A sag; Pearl River Mouth Basin
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Guangzhou Institute of Geochemistry, Chinese Academy of Sciences (GIGCAS)IS1050
Issue or Number:8
Record Number:CaltechAUTHORS:20091019-101732280
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:16378
Deposited By: Jason Perez
Deposited On:19 Oct 2009 19:42
Last Modified:03 Oct 2019 01:10

Repository Staff Only: item control page