Jiuquan Basin, located on the western part of the northern endge of Qilian orogenic belt, is a petroliferous basin on western end of the Corridor basin group. It is a subbasin of Jiuquan Basin. The exploration of several medium-to high-capacity industrial oil wells in the Lower Cretaceous strata indicates Jiuxi Basin the favourable geological conditions for hydrocarbon accumulation. People have never come to an agreement to the origin of the Jiuquan Basin. So, we studied the sedimentary facies of the Early Cretaceous strata at Hongliuxia Section of Jiuxi Basin and believe that sedimentary setting experienced four evolution stages are deep lake subfacies , pro fan-delta subfacies, fan-delta front subfacies, and fan-delta plain subfacies. Therefore the Jiuxi Basin can be divided into three evolutionary stage of embryonic rift,spread rift and basin shrinkage, having a bilayer structure of superposed sag and depression. By analyzing the exploration data and regional correlation, we propose that that tectonic setting of Cretaceous strata in Jiuxi Basin is similar to that of Mesozoic land facies basin in east China. Through comparing to the origin of early Cretaceous extensional rift basin group in east China, we think that the formation and evolution of the basin is affected by the subduction of Pacific Plate and the southward drift of Siberia Plate.%酒泉盆地位于祁连造山带北缘西部,是走廊盆地群西端的一个重要的富油气盆地,酒西盆地是酒泉盆地的次级盆地之一,下白垩统已钻获多口中、高产工业油井,显示具备优越的油气地质条件.白垩纪酒泉盆地的成因问题一直存在争议.对酒西盆地红柳峡早白垩世地层的实测剖面沉积相研究,得出当时的沉积环境具有由深湖亚相向前扇三角洲亚相、扇三角洲前缘亚相到扇三角洲平原亚相的演化序列,说明盆地发展经历了初始断陷阶段、断陷扩张阶段和坳陷阶段,是具有典型的断-坳双层结构的盆地.在结合盆地勘探认识的基础上,通过区域对比,提出白垩纪酒泉盆地与我国东部中生代陆相沉积盆地具有相似的构造背景,类比中国东部早白垩世伸展断陷盆地的成因,提出盆地的形成与演化受到太平洋板块俯冲及西伯利亚板块向南漂移的影响.
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