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德令哈地区的基性麻粒岩呈透镜状或脉状分布于长英质片麻岩和泥质片麻岩中。基性麻粒岩的主要矿物组成为紫苏辉石、单斜辉石、斜长石、角闪石 ,含有少量的钛铁矿、锆石等副矿物。单斜辉石中具有针状的斜方辉石和钛铁矿的出熔片晶 ,代表了高温条件下的出熔结构。采用不同方法的二辉石温度计 ,估算出其麻粒岩相的温度为 72 0～ 92 5℃。基性麻粒岩的微量及稀土元素分析显示其原岩的形成环境可能为大陆边缘环境。全岩及矿物的 Sm- Nd等时线年龄为 1791± 37Ma,代表了麻粒岩相的变质时代。基性麻粒岩及其围岩的 Nd模式年龄显示出这一地区可能有太古宙的地壳物质存在。
The basic granulites in the Delingha area are lenticular or veined in the feldspathic gneisses and argillaceous gneisses. The basic mineral composition of basic granulite is peridotopic pyroxene, clinopyroxene, plagioclase, amphibole, with a small amount of ilmenite, zircon and other minerals. Clinoptilolite in clinopyroxene and ilmenite out of the melting of crystalline, representing the high temperature conditions out of the melt structure. Using different methods of the pyroxene thermometer, the temperature of the granulite facies is estimated to be 72 0 ~ 92 5 ℃. Trace amounts of granulite and REE analysis of the basic granulites show that the formation of the original rocks may be the continental marginal environment. The whole rock and mineral Sm-Nd isochron age of 1791 ± 37Ma, representing the granulite facies metamorphic age. The Nd mode age of the basic granulites and their surrounding rocks shows that there may be Archean crustal material in this area.