川西前陆盆地的发展演化、地层充填及其对油气成藏的意义

前陆盆地构造位置重要、油气资源丰富，是盆地分析和油气勘探的重要领域。为此，利用构造、沉积及钻井等资料，综合研究了已经成为四川盆地天然气勘探的重要领域的川西前陆盆地的发展演化、地层充填及其对油气成藏的意义。结果表明，川西前陆盆地发展始于印支运动的卡尼期而终于喜山期；盆地的发展在各个时期表现出极大的差异性：沉积沉降中心的迁移、构造应力场的变化、构造格局的变化。上述三方面的差异性决定了川西前陆盆地天然气藏的生、运、聚、保条件。该区油气藏主要受前陆盆地形成过程中的坳陷和隆起带控制，燕山期形成的绵竹-盐亭隆起带、邛崃-新津隆起带是油气聚集的有利地区，也是川西前陆盆地油气勘探的主要区带。

EVOLUTION AND SEDIMENT FILLING OF WESTERN SICHUAN FORELAND BASIN AND THEIR SIGNIFICANCE OF HYDROCARBON ACCUMULATION

The foreland basin is a major area for basin analysis and petroleum exploration due to its important structural location and abundant oil/gas resources. Structural, sedimentary and drilling data are integrated to comprehensively study the evolution and sediment filling and their significance of hydrocarbon accumulation in western Sichuan foreland basin, an important area of gas exploration in the Sichuan Basin. The evolution of western Sichuan foreland basin initiated at Carnian stage of Indosinian epoch and ended in Himalayan epoch. The development of the foreland basin in different epochs is quite different in respects of migration of depocenter, variation of tectonic stress field, and change of tectonic framework. These differences determine the generation, migration, accumulation and preservation of gas in western Sichuan foreland basin. The occurrence of gas pools in the study area is mainly controlled by the down warped zones and uplifted zones in the process of foreland basin formation. Mianzhu Yanting and Qionglai Xinjin uplifted zones formed in Yanshan epoch are favorable for hydrocarbon accumulation, thus are the main plays for petroleum exploration in western Sichuan foreland basin.