吉林省延边地区两江构造堆叠带——汉阳屯推覆构造的发现及地质意义

Discovery and geological significance of tectonic stacking zones–Hanyangtun nappe structures in Liangjiang area,Yanbian, Jilin Province

华北地台北缘以夹皮沟北西向深大断裂及古洞河北西向深大断裂与吉黑褶皱造山带分界。地质构造复杂,经历了韧性、韧脆性及脆性等不同层次的变形作用,形成了复杂多样的构造格局;在吉林省延边地区获得推覆构造事件资料较少,笔者本次在两江地区汉阳屯一带发现推覆事件,推覆体由新太古代变二长花岗岩组成,其被推覆到南芬组粉砂岩之上,这一发现为区域构造单元划分提供有利依据。

The northern margin of the North China Platform is bounded by the north-westward deep fault of the Jiapigou,the north-westward deep fault of the Gudonghe and the fold-orogenic belts of Jilin-Heilongjiang area.Its geological structure is complex,and it has undergone different levels of deformation such as ductile,ductile-brittle and brittle,forming a complex and diverse tectonic pattern.There are few data on the nappe structure events in the Yanbian area of Jilin Province.The authors have found nappe events in the Hanyangtun area of the Liangjiang area.The nappe consists of the Archean metamorphic granite,which was overlaid onto the siltstone of Nanfen formation.This finding provides an important basis for the division of regional tectonic units.