下扬子北缘前陆盆地构造变形样式

TECTONIC DEFORMATION OF FORELAND BASIN IN THE NORTHERN PART OF LOWER YANGTZE AREA

何明喜 杜建波 古哲 谢其锋 马荣芳 张冬梅

He Mingxi Du Jianbo Gu Zhe Xie Qifeng Ma Rongfang Zhang Dongmei

中国石油化工股份有限公司 河南油田分公司, 河南 南阳 473132

He'nan Oil Field Branch Company, SINOPEC, Nanyang, He'nan 473132, China

下扬子北缘前陆盆地经历了印支、燕山、喜山等多期构造改造,构造环境经开裂扩张—碰撞拼合—拉伸断陷等多次转换,最终形成了上部拉伸、中部逆冲推覆、下部拆离滑脱的"三层楼阁"式分层构造变形组合的构造几何学模式.其构造变形主要受中三叠世扬子地块与华北地块的陆—陆碰撞造山作用控制,具有横向上强弱分带、垂向上形变分层的特征.可划分为伸展变形、冲断褶皱变形、拆离滑脱变形等3种构造变形样式.

Owing to the tectonic deformations during the Indosinian,Yanshan and Xishan epochs,the tectonic environment of foreland basin in the northern edge of lower Yangtze area changes from rift,collision matching to stretch rift,and ultimately results in a structural geometrical model of "3 tiers pavilion" with stretch in the top,thrust nappe in the middle and decoupling slip in the bottom.The tectonic deformation is mainly controlled by the collision orogenesis of Yangtze and North China platforms during the Middle Triassic with the characteristics of strong-weakness zoning horizontally and deformation layering vertically.The deformation style includes 3 types: stretching deformation,thrust fold deformation and decoupling slip deformation.

中国石油化工集团公司科技项目(P02039).

https://doi.org/10.11781/sysydz200604322