华北克拉通西北缘(狼山段)边界特征及其构造意义

The northwestern boundary location on Langshan area of North China Craton and its tectonic significance

关于华北克拉通西北缘(狼山段)边界位置有那仁宝力格-获各琦-赛乌素断裂和查干毛道-甘其毛道断裂存在两种观点。为确定边界位置,本文通过对比那仁宝力格-获各琦-赛乌素断裂两侧中新元古界形成时代、沉积环境及侵入岩Hf同位素,并结合地球物理场特征,确定克拉通应以宝音图群北侧的查干毛道-甘其毛道断裂为界线。那仁宝力格-获各琦-赛乌素断裂形成于晚古生代,具有分割两侧古生代地质体特征及演化历史的意义。该边界的确定为该区构造单元的划分及成矿规律的总结具有指导意义,同时提出东侧的白云鄂博-化德-多伦-赤峰断裂作为华北克拉通北缘边界是否合适。

There are two views on the boundary location of the northwest margin of the North China Craton(Langshan Area):the Narenbaolige-Huogeqi-Saiwusu fault or the Chaganmaodao-Ganqimaodao fault.In order to determine the boundary location,we compared the Meso-Neoproterozoic depositional age,depositional environment and Hf isotopes of intrusive rocks on both sides of the Narenbaolige-Huogeqi-Saiwusu fault,combined with geophysical characteristics,and determined that the Chaganmaodao-Ganqimaodao fault should be the northwestern boundary of North China Craton.The Narenbaolige-Huogeqi-Saiusu fault was formed in the late Paleozoic,which has the significance of dividing the geological characteristics and evolutionary history of the Paleozoic on both sides.This boundary has guiding significance for the division of tectonic units and the summary of metallogenic law in this area.At the same time,we proposed whether the Bayan Obo-Huade-Duolun-Chifeng fault is suitable for the northern boundary of North China Craton.