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位于塔里木地台西北缘的阿克苏地区,前寒武系由阿克苏群、巧恩布拉克群和乌什群组成。阿克苏群钠长石英片岩的 Rb-Sr 全岩等时线年龄为962Ma,与其互层产出的蓝闪片岩和绿帘阳起片岩的 Rb-Sr 全岩等时线年龄为944Ma,推测阿克苏群原岩生成年龄要大于 1000Ma。巧恩布拉克群为一套巨厚的碎屑岩,根据沉积分析资料,属于海下扇浊流沉积。乌什群由水成的尤尔美那克组、苏盖特布拉克组和奇格布拉克组浅海碳酸盐岩石组成。上述三群的时代分别归属于前晚元古代、晚元古代早期(青白口纪)和晚元古代晚期(震旦纪)。在巧恩布拉克群和乌什群中分别发育了一套碎屑流沉积物和陆地冰川沉积物。两种沉积物的杂砾岩层虽然具有相似的块状冰碛岩外貌,但砾石成分、磨圆度和分选程度存在明显差别。在巧恩布拉克群杂砾岩层中保留有滑塌前的原生砂岩的层状构造和滑塌过程中产生的包卷层理,有力地证明了它的碎屑流成因。乌什群尤尔美那克组发育了诸多的冰成特征,特别是冰溜面的发现和以块状杂砾岩为主的冰川沉积序列指示了陆相冰川沉积环境。
Located in the Aksu area on the northwestern margin of the Tarim platform, the Precambrian consists of Aksu, Qiambulake and Wushu. Aksu group albite quartz rock Rb-Sr whole rock isochron age of 962Ma, and interbedded with the production of blue flash schistoliths and green glauconschist Rb-Sr whole rock isochron age of 944Ma, speculated that Aksu Qun The original rock generation age is greater than 1000Ma. Qiambulake group is a set of huge clastic rock, according to sedimentary analysis data, belonging to turbid flow deposition of the sea. The Uschu group is composed of the Jürnchenak Formation, the Sugett Braque Formation, and the Chilblack Formation shallow-sea carbonate rocks. The above three groups of epochs belong to the previous Proterozoic, the Late Proterozoic (Qingbaikouji) and the late Proterozoic (Sinian) respectively. A set of debris flow sediments and terrestrial glacial sediments were developed in the Qiambulake and Wushu respectively. Although the conglomerate rocks of the two sediments have a similar appearance of massive moraine rocks, there is a clear difference in gravel composition, roundness and sorting degree. The stratiform structure of the native sandstone before collapse and the lamellar formation during the slump remain in the Qiambulake conglomerate reservoir, which proves its origin of debris flow strongly. The Wushun-Yulongkun Formation developed many ice-forming features, especially the discovery of the ice-slip surface and glacial sedimentary sequence dominated by massive conglomerate rocks, indicating the continental glacial sedimentary environment.