位于中亚造山带与塔里木克拉通结合部位的新疆库鲁克塔格是研究中亚造山带及塔里木克拉通关系的一个关键地区.野外观测、显微构造分析以及Ar-Ar测年结果揭示:(1)库鲁克塔格地区震旦纪一早古生代岩系地层变形样式为底部强烈褶皱,面理密集向北缓倾,顶部褶皱较宽缓、劈理稀疏向北陡倾,构成具有向南构造指向的铲式构造样式；(2)库鲁克塔格地区基底与盖层之间存在一条E-W走向、厚度约2km的韧性滑脱带,带内普遍发育糜棱岩及“A”型剪切褶皱等,糜棱岩面理向N或S缓倾、拉伸线理向NW或SE倾伏,不对称旋转构造及糜棱岩中石英晶格优选方位图(EBSD测试)指示韧性滑脱带上盘滑脱方向为自NW向SE；(3)韧性滑脱带中糜棱岩内白云母的Ar-Ar测年结果表明滑脱时代早于383Ma.滑脱-褶皱构造是塔里木地块与中天山岩浆弧带碰撞后发生陆内俯冲的产物,说明塔里木盆地东北缘库鲁克塔格存在早古生代造山事件.%Located at the junction part between the Tianshan orogenic belt and the Tarim craton, Kuruktag area in Xinjiang is a key area for the study of the relationship between the Central Asian orogenic belt and the Tarim craton. According to structural and micro -structural investigations and Ar ~ Ar dating of Kuruktag area, the authors have reached the following conclusions: (1) Sinian ~ Early Paleozoic cap rocks were deformed obviously at the bottom with dense cleavages dipping gently northward, but they were deformed slightly at the top with sparse cleavages steeply dipping northward, forming southward spread spade-shape structural style in NS direction. (2) A decollement exists between the cover rocks and the basement stretching in EW direction with a width of 2 km, characterized by "A" type folds, mylonites, gentle mylonite foliation, whose stretching lineation plunges northwest or southeast. Studies of asymmetrical rotational structure and crystallographic preferred orientations of quartz in mylonites (EBSD analysis) indicate a movement of the hanging wall of the ductile decollement in SE direction. (3) Ar - Ar dating result of the muscovite in the mylonite from the ductile decollement shows that the decollement was formed earlier than 383 Ma. The decollement was a product of the intercontinental subduction after the collision event between the Tarim block and the Central Tianshan magmatic arc, and it means the existence of the early Paleozoic orogenic event in Kuruktag area on die northeast margin of Tarim Basin.
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