摘要
本文根据近几年在恒山和五台地区所获得的大量同位素年代学资料，统计发现恒山杂岩的同位素年龄峰值比五台杂岩大致要晚20Ma，即深层次地壳有更持久的热演化历史，为恒山-五台岛弧根带-岛弧提供了一个佐证。综合分析同一期不同地质记录，从而将五台杂岩和恒山杂岩从新太古代晚期至古元古代末期的演化划分为5期区域性事件。华北东西陆块的俯冲碰撞应该发生在2．55～2．50Ga期间。
Statistics of many new isotopic age data show that the peak value of Hengshan complex （2 520 Ma） is some 20 Ma younger than that of Wutai complex （2 540 Ma）. This serves as the evidence that Hengshan complex might be the arc root of Wutai complex. Based on an integrated analysis of various geological records, the authors have divided the evolution of Wutai-Hengshan Precambrian complex into five stages. It is thus inferred that the central orogeny should have taken place between 2.55 and 2.50 Ga in North China craton.
出处
《地球学报》
EI
CAS
CSCD
北大核心
2005年第B09期115-117,共3页
Acta Geoscientica Sinica
基金
本课题得到北京大学重点测试基金的资助.
