川东石炭系大气田成藏条件分析

川东地区是四川盆地稳定地块中的相对构造活动带，区内发育10排高陡构造带，90年代以来高陡构造带石炭系成组气田勘探获得巨大突破。本文着重讨论了石炭系气藏的成藏条件，指出形成石炭系大气田的各项有利条件，即具丰富气源的志留系、二叠系存在异常高压提供足够的动力促使天然气向区域孔洞型储集层石炭系常压层运移，高陡构造带成串分布的高点是形成成组气田的有利圈闭，石炭系在上覆阳新统高压封闭体系的严密保护下聚集成藏。

ANALYSIS OF FORMATION FACTORS OF CARBONIFEROUS LARGE SCALE GAS POOLS IN EAST SICHUAN

East Sichuan is a relatively tectonica active belt in the Sichuan blocks. In this region, there are ten rows of high and steep structural zones. Since 1990s, a great breakthrough has been made in the exploration of Carboniferous grouped gas pools in the high and steep structural zones. This thesis chiefly discusses formation factors of Carboniferous gas pools and favourable condition of forming Carboniferous large gas pools.It is considered that the Silurian and Permian strata with rich gas resources and abnormal high pressure provided driving force for the migration of natural gas to Carboniferous formation with regional vuggy reservoirs and normal pressure condition. Beads-shaped apexes distributed in the high and steep structural zones are the favourable traps for the oil and gas formation.The high pressure confining system created by the overlain Permian strata provided protection for the oil and gas accumulation.