摘要
松树沟超镁铁质岩体位于秦岭商丹断裂以北,是该地区出露最大的超基性岩体,以侵位方式与秦岭杂岩接触。该岩体主要由细粒纯橄榄岩、中粗粒纯橄榄岩和斜辉橄榄岩组成。对松树沟超镁铁质岩体接触变质带榴闪岩中锆石包裹体成分及锆石微量元素含量进行了研究,结果表明松树沟超镁铁质岩体与相邻的镁铁质岩(主要是斜长角闪岩)不是同一构造旋回的地质体。斜长角闪岩先形成,之后松树沟岩体侵位其中。斜长角闪岩的地球化学特征显示其具有MORB和IAT两个端员组分特征,很可能是秦岭群的组成部分。
The Songshugou uhramafic pluton north of the Shangdan fault is the largest uhramafic body in the East Qinling Orogen and assumes the emplacement contract with the Qinling complex. The pluton is composed mainly of fine-grained as well as medium- and coarse-grained dunite and plagioclase-pyroxene peridotite. Debates exist concerning whether uhramafic rocks and adjacent mafic rocks were formed in the same tectonic cycle and whether they experienced a common metamorphism-deformation event or not. This paper presents new data on the inclusions and trace element concentrations of zircons from garnet amphibolites that occur in a metamorphic contact zone. Studies indicate that the uhramafic intrusion and adjacent amphibolites experienced different tectonic events, and the ultramafic pluton was emplaced in amphibolites formed before. Geochemical data suggest that amphibolites have characteristics of MORB and IAT and likely belong to the Qinling Group.
出处
《岩石矿物学杂志》
CAS
CSCD
北大核心
2009年第3期225-234,共10页
Acta Petrologica et Mineralogica
基金
中央级公益性科研院所基本业务费资助项目(K0810)
