龙门山北段天井山构造演化特征及物理模拟

Evolution characteristics and physical simulation of Tianjingshan structure in northern Longmenshan

李卿¹ 李忠权¹ 王森² 马启科¹ 李娟¹ 万双双¹

成都理工大学油气藏地质及开发工程国家重点实验室，四川 成都 610059 四川省安全科学技术研究院，四川 成都 610000

State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology, Chengdu 610059, China Research Institute of Safety and Science Technology of Sichuan Province, Chengdu 610000, China

根据地震、钻井、野外调查资料和平衡剖面法，模拟恢复天井山的造山过程，认为天井山地区的演化可划分为伸展拉张成盆阶段（震旦纪—中三叠世末）、陆隆伸展演化阶段（晚三叠世—中侏罗世末）、抬升剥蚀阶段（晚侏罗世—早白垩世末）和继承改造阶段（晚白垩世—现今）。通过构造物理模拟实验，初步证实了天井山地区印支期发育的薄皮构造是受南北向挤压应力与北西—南东向重力滑覆共同作用形成的；喜山期，天井山地区在北西—南东向挤压应力作用下变形序列为前展式逆冲叠瓦式构造组合；天井山构造存在多个滑脱层系，滑脱层上下形成分层变形、垂向叠置的不协调收缩构造变形。

The orogenic process of Tianjingshan was reproduced based on seismic, drilling, field survey data and equilibrium profile method. The evolution of Tianjingshan Region can be divided into extension basin(Sinian-Late Middle Triassic), continental emergence extension evolution stage(Late Triassic-Late Middle Jurassic), lifting and denudation stage(Late Jurassic-Early Cretaceous) and reformation succession stage(Late Cretaceous-present). Through structural physical simulation experiment, it is preliminarily confirmed that the thin-skinned structure developed during the Indo-Chinese epoch was formed by the combined action of the south-north extrusion stress and northwest-southeast gravity gliding; that during the Himalaya period, Tianjingshan Region was deformed into imbricate thrust structural combination; that the Tianjingshan structure has multiple decollement layers, which form incoordinated structural deformation with layered deformation and vertical superposition.

10.6056/dkyqt201301006