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在羌塘中部的白云母蓝闪石片岩和石榴石白云母片岩中发现透镜体产出的榴辉岩,大地构造位置位于龙木错-双湖板块缝合带的南侧.蓝闪石40Ar-39Ar年龄为220Ma,白云母40Ar-39Ar年龄221.9Ma.榴辉岩主要由石榴石、绿辉石、多硅白云母和金红石等矿物所组成,绿辉石含有32.7%~38.95%的硬玉分子.地质温压计估算表明,榴辉岩相变质作用发生在温度不超过500℃,压力在1.56~2.35GPa的条件.青藏高原羌塘榴辉岩的发现进一步说明羌塘中部可能存在印支期的板块缝合带,对探讨羌塘地区的古板块体制和演化具有重要意义.
The eclogites from the lens bodies are found in the muscovite and garnet muscovite schists in the central Qiangtang, with the tectonic positions located on the south side of the Longmucuo-Shuanghu plate suture zone.Blatonite 40Ar- The age of 39Ar is 220Ma and the age of 40Ar-39Ar of muscovite is 221.9Ma. The eclogite is mainly composed of minerals such as garnet, omphacite, polysiliciferous and rutile, and omphacite contains 32.7% -38.95% of jadeite. The geothermometer estimates show that the eclogite facies metamorphism occurred at a temperature not exceeding 500 ℃ and pressure between 1.56 and 2.35 GPa.The discovery of eclogites from Qiangtang in the Qinghai-Tibet Plateau further indicates that there may be Indosinian Plate suture zone, the Qiangtang area to explore the ancient plate system and evolution of great significance.