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柴达木盆地北缘的鱼卡河岩群是在最近几年区域地质调查和研究的基础上新建立的构造岩石单位,主要分布于绿梁山—锡铁山—沙柳河一带,由石榴白云石英片岩、石榴(蓝晶)白云片岩、二云片岩、黑云变粒岩、黑云角闪片岩、榴辉岩、石榴斜长角闪岩及大理岩等组成,以含榴辉岩为特征。在绿梁山地区,鱼卡河岩群呈不同规模的残块产于花岗闪长质—二长花岗质片麻岩之中。野外观察和变质作用特点显示,至少有一部分榴辉岩的原岩是鱼卡河岩群表壳岩的组成部分,在早古生代遭受了高压变质再造。根据从鱼卡河岩群及花岗片麻岩中获得的同位素年龄,结合两者的野外地质关系,初步确定鱼卡河岩群形成于中元古代。
The Yukaheyan Group in the northern margin of the Qaidam Basin is a newly established tectonic rock unit based on regional geological survey and research in recent years. It mainly distributes in the area of Luliangshan-Xieshan-Shaliuhe River and is composed of dolomite of pomegranate Schist, pomegranate (aquamarine) dolomite, dolomite, biotite granulite, biotite hornblende, eclogite, porphyry amphibolite and marble, and are characterized by eclogite. In the Lvliangshan area, the remnants of the Yukaheyan Group with different scales are produced in granodiorite-monzonitic granitic gneiss. The characteristics of field observation and metamorphism show that at least part of the original rock of eclogites is a component of the Yukaheyan rock and has been subjected to high-pressure metamorphism reconstruction in the early Paleozoic. Based on the isotopic ages obtained from the Yukaheyan Group and the granitic gneisses, and combining the field geological relationship between the two, it was initially determined that the Yukahe Group formed in the Mesoproterozoic.