Based on the knowledge of sedimentology, geochemistry and global tectonics, the authors systematically analyzed the well core samples of Keluke and Zhabusagaxiu Formations from Well Shixian 1 located in the Shihuigou area on the northern margin of the Qaidam Basin. The content of major and trace elements and the relevant discrimination diagrams demonstrate that the clastic rocks of Keluke and Zhabusagaxiu Formations from Well Shixian 1 were formed in the passive continental margin, and their geo⁃chemical characteristics are extremely different from clastic rocks with other tectonic histories. The sandy conglomerates of Keluke and Zhabusagaxiu Formations were highly recycled (or the igneous rocks of the study area were highly differentiated) and experi⁃enced moderate to high weathering. The clastic rocks were sourced from Post Archean Eon crust dominated by acidic igneous rocks. On the basis of the geochemical study of the clastic rocks and previous study results, the northern margin of the Qaidam Basin is re⁃garded as a passive margin cratonic basin controlled by Zongwulong trough expansion in the north. The clastic rocks were sourced from the base of the Paleozoic orogenic belt in the northern Qaidam. The transgression was from north to south and the depositional systems were distributed from south to north, showing an overall pattern with mountains in the south and oceans in the north.%在沉积学、地球化学、大地构造学等理论的指导下，对柴达木盆地北缘石灰沟地区石浅1井克鲁克组-扎布萨尕秀组钻井岩心样品进行了系统的测试分析。主量、微量元素含量及相关判别图解表明，石浅1井克鲁克组-扎布萨尕秀组碎屑岩形成于被动大陆边缘盆地，同时体现出与其他构造背景碎屑岩差别极大的地球化学特征，克鲁克组及扎布萨尕秀组砂砾岩具有较高程度的沉积再循环(或源区岩浆岩高程度分异)及中等偏高的风化程度，碎屑物质来自于以酸性岩浆岩为主的后太古宙大陆上地壳。在碎屑岩地球化学研究的基础上，结合前人研究成果认为，柴北缘地区晚石炭世沉积盆地类型为受北侧宗务隆海槽扩张控制的被动大陆边缘克拉通盆地，碎屑物质来源于由酸性岩浆岩组成的柴北缘古生代造山带基底部分，海侵自北向南、沉积体系自南向北展布，总体呈现南山-北海的盆山格局。
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