Since the late Paleozoic, the south Tianshan Mountain has gone through a series of collision and micro-plate collage events, which have had obvious reflection in the sedimentation and tectonic evolution of northern Tarim basin. The analysis of depositional provenance is an important method for understanding basin evolution and interpreting tectonic background, and is also the first prerequisite for confirming the evolution of the basin. The variation in the composition of depositional provenances reflects the relationship between the uplift of basin margin orogen and the basin subsidence. With the improvement of modem analytical techniques, the provenance analytical methods have increased in number, become gradually perfected in quality and complemented each other. Based on Dickinson's provenance analytical method, the authors studied and analyzed sandstone detrital composition and source rocks of Upper Carboniferous sandstone along different geological sections in northern Tarim basin. The results show that the major types of the Upper Carboniferous sandstone are quartz sandstone and lithic quartz sandstone, with low compositional maturity, and the average Q/(F+ L) in Cedaya, Dashankou hydropower station and Bayinbuluke geological section are respectively 1.80, 3.11, 3.32. The detrital composition is mainly quartz and subordinately feldspar and some rock debris, with minor organic matrix or biotite. According to the study of sandstone detrital compositions, sandstone of Upper Carboniferous Ayilihe Formation in northern Tarim basin is composed averagely of 70.7% quartz (53%~86%), 7.1% feldspar (5%~17%), and22.5 % rock debris (20%~30%). Metamorphic debris and sedimentary debris are mainly existent in this area, while in Cedaya, volcanic debris possesses 42%. On the basis of Dickinson's triangular plot and the characteristics of rock debris, the Upper Carboniferous provenance in northern Tarim basin is characterized by the recycled orogen type, and the primary attribute is the suture zone for subduction and collision orogeny, with minor arc orogenic attributes. In combination with the late Carboniferous lithofacies-paleogeography of northern Tarim, it is held that the source of the northern Tarim basin might have been derived from the ancient Tianshan orogenic belt in the north.%南天山在晚古生代以来经历的一系列碰撞和微板块的拼合事件在塔里木盆地北缘的沉积作用和构造演化中都有明显的反映,而沉积物物源分析是认识盆地演化、解释构造背景的重要途径和方法.根据对塔里木盆地北缘地区多个剖面的研究,上石炭统阿依里河组砂岩碎屑组分以石英为主,其次是长石及各种岩屑,有时含有机质杂基及云母.其中石英平均含量为70.7％ (53％ ～86％),长石平均含量7.1％(5％～17％),岩屑平均含量为22.5％(20％ ～30％).物源分析结果表明,砂岩物源主要来自再旋回造山带,并且主要具俯冲消减的缝合带和碰撞造山属性,少量具弧造山属性.结合塔里木北缘晚石炭世的岩相古地理特征,认为物源可能来自于北侧的古天山造山带.
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