论四川盆地天然气勘探前景

中石油及其前身已在四川盆地从事天然气勘探开发工作50余年,截至2005年底累计探明天然气地质储量逾8400×10⁸m³,累计生产天然气超过2300×10⁸m³,年产量现已超过120×10⁸m³,已成为国内目前最大的产气区。对于该盆地进一步勘探前景如何的命题,从以下4个方面给予了论证：一是资源丰富、勘探成果持久不衰，近期仍有大发现；二是要辩证地认识盆地油气地质的复杂性，探索新规律，解放新领域；三是寻求地质认识和勘探技术进步是勘探突破的关键；四是继续以盆地两大地质体系（海相古隆起体系及陆相前陆盆地体系）和8套裂缝-孔隙性储集层（中上寒武统白云岩、石炭系白云岩、上二叠统长兴组生物礁白云岩、下三叠统飞仙关组鲕状白云岩、下三叠统嘉陵江组粒屑白云岩、中三叠统雷口坡组藻粒白云岩、上三叠统须家河组长石岩屑石英砂岩和中上侏罗统红层砂岩）为对象获取更多的天然气资源量及优质储量。据此得出结论：四川盆地天然气勘探前景是广阔的，但勘探难度会逐步加大。

NATURAL GAS EXPLORATION PROSPECT IN THE SICHUAN BASIN

Both PetroChina and its predecessor have been engaged in natural gas exploration and development in the Sichuan Basin for over 50 years and so far achieved accumulative proven reserve of over 840 billions m3 and cumulative production of over 230 billions m3 with annual production exceeding 12 billions m3, which made the Sichuan Basin the largest natural gas production base in China. This paper discusses the exploration prospect in the Sichuan Basin in four aspects as follows: ①the Sichuan Basin abounds in natural gas resources and enjoys sustained exploration discoveries in the past and substantial discovery continues to occur in recent years; ② complexity of petroleum geology in the Sichuan Basin should be viewed dialectically and new theories should be explored and new fields should be liberated; ③the key to exploration breakthrough is geological theory and exploration technique innovation; ④more resources and high quality reserve may be obtained by focusing exploration efforts on two kinds of geological systems (marine paleohigh system and continental foreland basin) and eight types of fracture pore reservoirs (namely, middle and upper Cambrian dolomite, Carboniferous dolomite, upper Permian Changxing Formation biohermal dolomite, lower Triassic Feixianguan Formation oolitic dolomite, Jialingjiang Formation dolorudite, middle Triassic Leikoupo Formation algal clastic dolomite, upper Triassic Xujiahe Formation feldspathic quartzine, and middle and upper Jurassic redbeds sandstone). It is concluded that natural gas exploration prospect in the Sichuan Basin is bright but under the impact of increasing difficulty.