川西拗陷东西向弧形构造带与基底断坡的关系  

Relationship between the basement uplift and the arc structure in the Western Sichuan Depression,China

作　　者：叶泰然[1] 刘殊[1] 张虹[1] YE Tairan;LIU Shu;ZHANG Hong(Southucvest Petroleum Branch Corrzpany of SINOPEC,Chengdu 610041,China)

机构地区：[1]中国石油化工股份有限公司西南油气分公司,成都610041

出　　处：《成都理工大学学报（自然科学版）》2018年第3期257-267,共11页Journal of Chengdu University of Technology: Science & Technology Edition

摘　　要：川西拗陷中段发育3~5个近东西走向的弧形构造,纵向上发育多个大中型气藏的孝新合构造带为其中之一,研究其形成机理对油气勘探具有重要意义。基于连片三维地震资料编制构造图,采用三维可视化逆光照射方法描述其构造体系,依据基底特征、构造应力方向,分析不同构造体系形成时期及机理。其构造特征为:震旦系基底发育大型的龙泉山古隆起,古隆起北侧发育2~3个近东西向的断坡,拗陷内的近东西向弧形构造均位于基底断坡上方,且与秦岭造山带平行。印支期龙门山北段隆起形成NW-SE、N-S向挤压应力,燕山期大巴山-米仓山形成N-S向挤压应力,龙泉山古隆起以及北侧的断坡形成阻挡,由此形成多组系近东西向弧形构造,该构造体系在喜马拉雅期继承性发展和被改造。基底古隆起及其北侧的断坡控制了上覆地层的构造运动学模式。3-5 east west trending arc structures with multiple gas bearing reservoirs occur in the middle section of the Western Sichuan Depression and the Xiaoquan Xinchang Hexingchang structural belt is the largest one. Based on the basement character and tectonic stress direction, the tectonic system, the forming stage and mechanism are described and analyzed by means of backlight illumination of 3D visualization technique. It shows that a large basement uplift （Longquanshan uplift） in the Sinian period developed in the Western Sichuan Depression. On the north side of the Longquanshan uplift, there are 2 or 3 near east west trending fault blocks with east west trending arc structures on the ramp of those fault blocks, parallel to the Qinling Mountain range. The study also indicates that the NW SE and N S compressional stresses from Longmenshan uplift of Indochina age, N S compressional stress from Daba Micang of Yanshan age, along with Longquanshan uplift and itsnorthern faulting system resulted in a serial of near east west trending arc structures. The structure system was further developed and modified by tectonic activities in Himalayan period and the overlaying strata are generally controlled by the basement uplift and faulting system developed in the north side of the depression.

关 键 词：基底古隆起 断坡 孝新合构造带 形成机理 川西拗陷 

分 类 号：P542[天文地球—构造地质学]