摘要
南川地区经历了多期构造运动影响,区内构造复杂,是页岩气勘探的有利区。根据区域构造背景和地震资料精细解释,结合其成因,将构造样式分为基底卷入型、盖层滑脱型和构造样式叠加3类,分析各构造样式及组合的典型剖面,探讨其形成时期和成因机制。南川地区动力机制来源于逆冲推覆构造作用,推覆应力来自东部雪峰陆内造山带,构造样式由青龙乡的基底断层逆冲过渡到平桥的断弯褶皱、叠瓦构造及其上变形层的背冲构造,再往北西变为东胜的断展褶皱及其上变形层的对冲构造、叠瓦构造,继续往西北形成南川断鼻斜坡带。在此基础上,将南川地区划分为东部冲断带、中部断褶带、西部斜坡带3个构造带,中部断褶带是页岩气勘探的有利目标。
The experience of multiple periods of tectonic movement and its complex structural characteristics make Nanchuan area a favorable area for shale gas exploration.According to the regional tectonic background and detailed interpretation of seismic data and its genesis,the tectonic styles are divided into 3 types of basement involved type,seal decollement type and tectonic style superposition type.This paper analyzed the typical profiles of various structural styles and their assemblages,and studied their formation period and genetic mechanism.The dynamic mechanism of this region was derived from the thrust nappe structure,and the thrust stress came from the eastern Xuefeng intracontinental orogenic belt.The tectonic styles started from the basement fault thrust in Qinglongxiang,to the fault-bending fold and imbricated structure and the backthrust of its upper deformation layer in Pingqiao,and moved northwestwards to fault propagation fold and the ramp structure and imbricated structure of its upper deformation layer in Dongsheng,finally went northwestwards to form the Nanchuan fault nose slope belt.Accordingly,Nanchuan area is divided into 3 tectonic belts:the eastern thrust belt,the central fault-fold belt and the western slope belt.It is pointed out that the central fault-fold belt is a favorable zone for shale gas exploration.
作者
孙小琴
Sun Xiaoqin(Petroleum Exploration and Production Research Institute,Sinopec East China Oil and Gas Company,Nanjing 210011,Jiangsu,China)
出处
《地质学刊》
CAS
2020年第1期102-107,共6页
Journal of Geology
基金
国家科技重大专项“彭水地区常压页岩气勘探开发示范工程”(2016ZX05061)。
关键词
构造样式
页岩气
有利区带
南川地区
tectonic style
shale gas
favorable zone
Nanchuan area
