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在中国西天山伊什基里克山一带，发育有一系列橄榄辉长岩、橄长岩、辉长岩、辉绿岩床和岩墙群，同位素年龄为２７７～２９７ Ｍａ。其中哈拉达拉层状橄榄辉绿辉长岩－辉绿辉长岩体（又称大桥岩体）规模最大，约２５．５ ｋｍ２。根据近年来的实地研究，认为该岩体形成于伊犁盆地石炭一二叠纪裂谷带发育的构造背景之下，既有大量碱性玄武岩和火山碎屑岩，又有一定数量的基性—超基性杂岩和层状辉长岩侵入体，经历了稳定—亚稳定—稳定的演化史，有可能代表着裂陷达最大深度时的一次基性岩浆活动。
In the area of the Ishikilike Mountain in the western Tianshan Mountains, China, there are a series of olivine gabbro, gabbro, gabbro, diabase beds and dyke swarms with isotopic ages of 277-297 Ma. Among them, the alluvial-gabbro-dacite gabbro (also known as the bridge rock body), the largest in the Allahabad, is about 25.5 km2. According to field research in recent years, it is considered that the rock mass is formed under the tectonic setting of the Carboniferous-Permian rift zone in the Ili Basin, which contains both a large amount of basic basalts and pyroclastic rocks and a certain amount of basic- The ultramafic complexes and layered gabbro intrusions have undergone a stable-metastable-stable evolution history and may represent a basic magmatic activity at the maximum depth of the rifting.