从全球海相古生界油气田地质共性看四川盆地海相地层天然气勘探方向

DISCUSSING THE MARINE PROSPECTS IN SICHUAN BASIN ACCORDING TO THE COMMON GEOLOGICAL CHARACTERISTICS OF GIANT PETROLEUM PROVINCE ON PALEOZOIC MARINE IN THE WORLD

总结了全球海相古生界大油气区的共同地质特征 ,研究了四川盆地海相古生界与国外海相古生界地质条件的相似性 ,认为四川盆地仍具有继续发现大油气区的地质条件。对四川盆地来说 ,层状孔隙性储层是当前天然气勘探的主要领域 ,被动大陆边缘坳陷是今后探索的大方向 ,古隆起上的似层状风化壳储层值得继续重视。结合四川盆地勘探现状和发展趋势 ,重点论述了川西地区 3个潜在的勘探领域 :1川西二叠系栖霞组生屑滩白云岩储层 (该领域将可能成为继川东石炭系白云岩层状储层和川东北三叠系鲕滩白云岩层状储层之后的战略接替领域 ) ;2晚古生代被动大陆边缘坳陷——川西逆冲带古生界 (其中矿山梁地区是目前的战略突破口 ,枫顺场构造为战略准备区 ) ;3乐山龙女寺古隆起带震旦系似层状风化壳孔洞性储层 (川西大兴场、汉王场的构造裂缝发育区是勘探的有利目标区 )

Paleozoic marine petroleum is significant exploration domain over the world. The authors conclude the common petroleum geological characteristics of giant petroleum province on Plaeozoic marine abroad, and compare it to that of Sichuan basin. There are many similar Petroleum geologic conditions of forming giant gas province Sichuan basin. The layer porous reservoir is main exploration domain. The passive continental margin is worthy prospect. The similar layer crest reservoir should be paid attention to continue. Connecting to the exploration status and progress trend. There are three potential prospects: ①Dolomite reservoir transferred from biologic debris beach in Qixia formation of Permian will be the succedent exploration domain after the layer porous reservoir of Carboniferous dolomite and Triassic oozite beach dolomite. ②The upper Paleozoic of thrust belt in western Sichuan basin, lied in passive continental margin in later Paleozoic which is benefit to from giant petroleum province, have the advantageous petroleum geological conditions, of which Kuangshanliang structure is available to exploration nowadays and Fengshunchang structure will be the important preparative exploration area. ③The key restricted factor of gas exploration is development degree of structural crack on the Cambrian formation in the Leshan Longnusi ancient uplift, as being of similar layer crest reservoir. Structured cracks developed fine in the Daxingchang structure and Hanwangchang structure, which will be the favorable exploration target area.