The Tectonic Environment,Typical Gas Pools and Exploration Direction of Coal type Gas Provinces in China
- Received Date: 1999-05-12
- Publish Date: 1999-12-10
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Key words:
- types of coal-type gas pools /
- tectonic /
- setting /
- gas geochemistry /
- tectonic reversion in Northwest china
Abstract: The coal type gas resource of Mesozoic mainly concentrates on the North China where the Northwest area is the most favorable region, and the gas source rocks are almost Jurassic coal series.The Turpan Basin is a typical coal type gas basin where C1/C1-5 value of HongTai 2 gas pool is 0.887,and its δ13C1-4 values and 40Ar/ 36Ar ratio are -39.1‰,-26.5‰,-25.4‰,-25.2‰ and 571,respectively.And these indicate that the Middle Jurassic series are self generated and self reservoired coal type gas pools,and the reversion of tectonic environment is the special structural condition for source rock to generate and concentrate coalbed gases. The coal type gas resource of Cenozoic mainly concentrates on the rift valleys of continental shelf along the seawest of the East China,and the Upper Tertiary coal series and their chief source rocks,The Ya 13 1 gas field located in the South of HaiNan Province is also a typical one that its δ13C1,value varies from -39.9‰ to -35.5‰,δ13C2 value varies from -26.8‰ to -24‰,and its gas belongs to pyrolysis genesis.The high temperature tectonic environment (thermal gradient of the Earth exceeds 4℃/100 m)is the favorable factor for the Tertiary to generate hydrocarbon,however,anticline and fault trap is the most helpful structural condition of concentration and reservation.
Citation: | TAO Ming xin, XU Yong chang, CHENG Jian fa, SHEN Ping. The Tectonic Environment,Typical Gas Pools and Exploration Direction of Coal type Gas Provinces in China[J]. Acta Sedimentologica Sinica, 1999, 17(4): 620-626. |