摘要
四川盆地早古生代曾发生澄江、桐湾、云贵、冶里及加里东等5次地壳运动,其动力主要来自印度板块的向北俯冲和欧亚板块的向东漂移,并与青藏板块相碰撞,使青藏板块迅急向东,在盆地西部龙门山一带的薄弱地带发生断裂,致使青藏板块向东逆覆于扬子地台板块之上,相继四川盆地形成。5次地壳运动使龙门山大断裂带规模一次比一次大,使下古生界油气勘探储层也逐渐东移,勘探范围也逐渐变小。经勘探证实,共形成了雅安—龙女寺、泸州和天井山3个古隆起,是油气勘探的有利地区,特别是雅安—龙女寺古隆起区,不但规模大,各时期碳酸盐岩储层发育,局部构造多,且其西北翼遭受剥蚀的程度较深,经大气淡水长期淋溶,各储层必然会产生大量的古岩溶缝、洞,当其彼此纵横向相互交切后便可形成一个庞大的缝、洞网络空间,对油气聚集成藏十分有利。泸州古隆起和天井山古隆起上,也有较多局部构造可供钻探下古生界碳酸盐岩储层。
Early Paleozoic of Sichuan Basin underwent five crustal movements, that is, Chengjiang movement, Tongwan movement, Yungui movement, Yeli movement, and Caledonian movement, caused by the northward subduction of Indian Plate and the eastward drift of Eurasian Plate. The two Plates collided with Qinghai-Tibet Plate, causing the latter to swift to the east and collapse in weak zone of Longmen mountain area of western Sichuan Basin. As a result, Qinghai-Tibet Plate reversed eastward and covered Yangtze platform plate, and Sichuan Basin was formed in succession. Because of the five crustal movements, the big fault zones in Longmen Mountain got larger and larger in scale, as a result petroleum exploration reservoirs of Lower Paleozoic moved towards the east gradually and the exploration range got smaller. Exploration here proved that the Yaan-Longnvsi palaeohigh, the Luzhou palaeohigh, and the Tianjingshan palaeohigh were formed, which are favorable for petroleum exploration. In particular, the Yaan-Longnvsi palaeohigh is large, carbonate reservoirs here developed in each period, and there are also many local structures. Moreover, the northwest wing was eroded heavily and was leached by meteoric water for a long time. A great number of ancient karst fissures and caves emerged in all reservoirs. When they crossed each other vertically and horizontally, a giant fissure and cave system would be formed, which is very good for hydrocarbon accumulation and reservoir formation. There are also many local structures in Luzhou palaeohigh and Tianjingshan palacohigh, and they could be used for Lower Paleozoic carbonate reservoir drilling and exploration.
出处
《中国石油勘探》
CAS
2013年第5期15-23,共9页
China Petroleum Exploration
关键词
四川盆地
下古生界
桐湾运动
加里东运动
油气勘探
Sichuan Basin, Lower Paleozoic, Tongwan movement, Caledonian movement, petroleum exploration
