摘要
医巫闾山岩体是医巫闾变质核杂岩的重要组成部分。根据医巫闾山地区花岗岩变形特征及与周围构造带的相互关系,确定医巫闾山岩体为同伸展侵位的岩体,且以岩床的形式顺层侵入在医巫闾山伸展型韧性剪切带之中,修正了前人挤压环境下岩浆侵位的观点。医巫闾山岩体及尖砬子山岩体的侵位时间在160Ma左右,表明医巫闾山地区及燕山地区中侏罗世晚期发生过强烈的地壳伸展运动,华北北部的构造体制在中侏罗世已经改变。区内中生代存在2期伸展作用:早期伸展作用发生在中侏罗世晚期,与医巫闾山岩体的侵位同期;晚期伸展作用发生在早白垩世,形成了瓦子峪拆离断层。
The Yiwulüshan pluton is an important part of the Yiwulü metamorphic core complex. Due to its deformation and relationship with surrounding tectonic belts, the Yiwulüshan pluton is determined as the syn-extensional granite. The pluton emplaced along or parallel to ductile shear zone as a bedding-sill, which modifies previous view that the pluton caused by magma emplacement under compressed environment. The emplacement time of both the Yiwulüshan pluton and the Jianlazishan pluton is about 160 Ma, which implies intensive crustal extension occurred in the Yiwulüshan and Yanshan region in late Middle Jurassic and the tectonic pattern of the northern part of North China had been transformed in Middle Jurassic period. There were two extensional stages in the area in the Mesozoic. The earlier occured in the Late Jurassic and accompanying with the emplacement of the Yiwulüshan pluton. The later extension occurred in the Early Cretaceous and resulting in the formation of the Waziyü detachment fault.
出处
《吉林大学学报(地球科学版)》
EI
CAS
CSCD
北大核心
2010年第4期971-978,共8页
Journal of Jilin University:Earth Science Edition
基金
国家自然科学基金重大研究计划项目(90814006)
国家自然科学基金项目(40972135)
关键词
变质核杂岩
拆离断层
同构造岩体
伸展构造
医巫闾山
metamorphic core complex
detachment fault
syn-tectonics pluton
extensional tectonics
Yiwulüshan