四川盆地石炭系四中心耦合天然气成藏过程

基于四川盆地石炭系天然气成藏经历了四中心(生烃中心、生气中心、储气中心、保气中心)交迁的观点,对石炭系天然气成藏过程重新恢复与梳理.其中,志留系烃源岩因各地进入生烃门限时间不同,使得其在空间上表现为多个生烃中心持续供烃.志留系排出的液态烃进入石炭系开江古隆起区域后,聚集形成大型构造-岩性古油藏.后经深埋,古油藏高温裂解...

Allegiance of four centers and pool-forming process of Carboniferous in Sichuan Basin of China

Based on the point that the gas pool-forming of Carboniferous in Sichuan Basin transited 4 centers,that is,hydrocarbon-generating center(Silurian hydrocarbon kitchen),gas-generating center(ancient oil pool),gas-reserving center(ancient gas pool) and gas-conserving center(nowaday gas pool),this paper recovers and straightens out the gas pool-forming process of Carboniferous.There are several hydrocarbon-generating centers that continue to supply the hydrocarbons in the area because the hydrocarbon-generating thresholds of Silurian in different regions are different.After the hydrocarbon liquid of Silurian assembled in the Kaijiang palaeohigh,a great structure-lithologic ancient oil pool formed.After deeply buried,the oil pool was split into an ancient gas pool due to high temperatures,and the gas-generating center changed into the gas-reserving center in situ.By the Himalayan movement,the palaeohigh(gas-reserving center) was dismembered,the old gas pool effused and the present gas pool formed.The rate of pool-forming of the Carboniferous gas pool in East Sichuan area is 9.15% through quantitative measurement of oil splitting and water-soluble gas under reservoir conditions.The research demonstrates that the generation and disappear of the centers are controlled by the tectonic movement of the basin and the key to the formation and distribution of the gas pool is the local structure format and feasibility of conservation.