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南天山榆树沟高压麻粒岩地体的主体为一套蛇绿岩。从该地体顶部单元的岩石中分离出的锆石绝大部分为浑圆形或椭球形，少量为两端略圆化的四方柱状晶体；镜下粒度分析结果显示分选良好的典型沉积特征；其ZrO2／HfO2比值在45—57之间。结合岩石的岩石学和地球化学特征，推测斜长石榴苏辉岩的原岩可能主要由来自洋岛的基性火山激浪沉积碎屑和洋底风化产生的粘土组成。所获锆石系单一来源的火山碎屑，故采用分组多颗粒锆石U-Pb同位素定年法，并依谐和图法，获得（440±18）Ma榆树沟蛇绿岩的形成年龄和（364±5）Ma的第一期（角闪岩相或麻粒岩相）变质年龄。该年龄值为确定古生代南天山洋的时、空展布，计算洋壳的俯冲速度，研究麻粒岩相蛇绿岩的形成机制提供了重要依据。
The main body of the Yushugou high-pressure granulite body in the southern Tianshan is a set of ophiolite. Most of the zircons isolated from the rocks in the top unit of the terrain are rounded or ellipsoid, with a small amount of tetragonal columnar crystals with slightly rounded ends. The microscopic grain size analysis shows the typical sedimentary features with good sorting. The ZrO2 / HfO2 ratio between 45-57. Based on the petrological and geochemical characteristics of the rocks, it is speculated that the protolith of the plagioclase pluton probably consists of the base volcanic sediments from the Ocean Islands and the clay produced by the oceanic weathering. The obtained zircons were from a single source of volcanic debris, so the grouping of multiparticulate zircon U-Pb isotope dating method was used and the age of (440 ± 18) Ma Yushugou ophiolite was obtained according to the harmonic map method. 364 ± 5) Ma metamorphic age of the first phase (amphibolite facies or granulite facies). This age value provides an important basis for determining the time and space distribution of the Palaeozoic South Tianshan Ocean, calculating the subduction velocity of the oceanic crust, and studying the formation mechanism of the granulite facies ophiolite.