四川盆地关键构造变革期与陆相油气成藏期次

Key tectonic change epoch and hydrocarbon accumulation periods of continental clastic reservoir in Sichuan Basin

金文正¹ 万桂梅² 崔泽宏³ 王俊鹏⁴ 杨孝群⁵ 白万奎⁶

中国地质大学（北京） 海相储层演化与油气富集机理教育部重点实验室，北京 100083 中国石油大学（北京）油气资源与探测国家重点实验室，北京 102249 中国石油勘探开发研究院，北京 100083 中国石油杭州地质研究院，浙江 杭州 310023 中国石化勘探南方分公司，四川 成都 610041 中国石化胜利油田分公司纯梁采油厂，山东 淄博 256300

四川盆地经历了多期构造演化，其关键构造变革期为印支期、燕山期及喜马拉雅期。通过对盆地内多个陆相碎屑岩油气藏的成藏时间进行对比分析，认为四川盆地碎屑岩油气藏总体上经历了3期成藏过程，即印支晚幕、燕山中—晚幕和喜马拉雅早幕，这与四川盆地整体经历的构造演化关键构造变革期一致。四川盆地西部地区北部气田的主要成藏时间早于南部，主要原因为川西地区构造活动的差异性；自西向东成藏时间具有逐渐变早的趋势，主要原因为四川盆地及其周边造山带构造活动的差异性，川西前陆盆地紧邻龙门山冲断带，从龙门山往盆地中部形变依次变弱。

Sichuan Basin has experienced multi-episode tectonic evolutions, including Indo-China movement, Yanshan movement and Himalayan movement. After analyzing the accumulation periods of some continental clastic reservoirs, it is considered that the continental clastic reservoirs in Sichuan Basin have also experienced three epoches of evolutions, namely Late Indo-China epoch, Mid-Late Yanshan epoch and Early Himalayan epoch, showing the consistency between tectonic evolution and hydrocarbon accumulation in Sichuan Basin. In the northern area of western Sichuan Basin, the accumulation time of gas reservoir is much earlier than that in the southern area because there are some differences among the tectonic activity of continental clastic reservoirs in western Sichuan Basin. The accumulation time becomes earlier from the west to the east and the reason may be differences of the tectonic activity between Sichuan Basin and its surrounding mountains. The foreland basins in western Sichuan Basin are close to the Longmen Mountain thrust belt. From Longmen Mountain to the center part of basin, the deformation becomes weaker.

10.6056/dkyqt201203001