Petroleum Systems of Jianghan Basin, Hubei Province, China
A. E. Cunningham, Steven Schaps, Dan McGregor, Guo Dongrun,
Wang Shizong, and Kenneth E. Peters
The Jianghan Basin is a Cretaceous-Tertiary nonmarine rift basin superimposed on a late Precambrian to Jurassic passive margin and foreland basin succession deformed by mid-Mesozoic folding and thrusting. Hence the basin has potential for superimposed petroleum systems.
Oil production is established in a Tertiary petroleum system developed in two major depocenters, the Jiangling (west) and Qianjiang (east) Depressions. Lacustrine source beds in the early Eocene Xingouzhui and late Eocene Qianjiang Formations generated hydrocarbons during local maximum basin fill in the Oligocene to present. Very early, low temperature generation of petroleum occurs where Type 1S Qianjiang Formation kerogen is present. Tertiary fluvial and deltaic sandstones form reservoirs that trap oil in highs or rollover structures formed by normal faulting and salt movement.
The pre-rift section contains large folds and good source-beds, but has high exploration risk. Factors limiting effectiveness of older petroleum systems are: 1, Uplift and erosion of thrust structures; 2, Overmaturation of pre-Permian source rocks prior to folding and thrusting; 3, Limited extent of secondary maturation of Late Paleozoic and Mesozoic source beds; and 4, Disruption of older traps and seals by widespread normal faulting. Production of hydrocarbons from Permian and Triassic rocks to the west of Hubei suggests that further seismic work and drilling are merited to evaluate pre-Tertiary potential in the Jianghan Basin.
AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California