【摘要】 基于大川中地区近期地震资料构造解释成果,结合钻井与盆地周边露头资料,探讨乐山—龙女寺古隆起不同时期不整合发育特征,研究古隆起构造演化过程及其对震旦系天然气成藏的影响。乐山—龙女寺古隆起发育震旦系不整合、古生界不整合、中生界不整合等重要区域不整合,根据不整合发育特征和剥蚀量,将其构造演化划分为雏形期、发育期、稳定埋藏期和调整定型期4个阶段,在此基础上,分析古隆起构造演化对震旦系天然气成藏的影响。结果表明:不整合控制了与古风化壳有关的古岩溶储集层的发育;古隆起构造演化控制了有机质热演化及油气运聚过程;古隆起形态变迁控制了构造圈闭的形成与消亡。更多还原

【Abstract】 Based on structural interpretation of the recent seismic data in central Sichuan Basin,combined with data of drilling and outcrops around the basin,this paper discusses the evolutional characteristics of unconformities at various stages in the Leshan-Longnüsi paleo-uplift,and studies the evolution of the paleo-uplift and its control on Sinian gas reservoir accumulation.Sinian,Paleozoic,Mesozoic and other major regional unconformities were developed in the Leshan-Longnüsi paleo-uplift.According to characteristics and denudation thickness of the unconformities,the paleo-uplift tectonic evolution is divided into four stages,namely,embryonic,developmental,stable burial,and finalization.The analysis of the effects of the tectonic evolution on the Sinian gas accumulation show that:(1) the unconformities controlled the development of ancient karst reservoirs relevant to paleo-weathering crust;(2) the tectonic evolution of the paleo-uplift controlled evolution of organic matter and hydrocarbon migration and accumulation;(3) morphological changes of the paleo-uplift controlled the formation and the mergence of structural traps.更多还原