鄂尔多斯盆地上三叠统延长组地层沉积厚度大、油气资源丰富，是该盆地油气勘探重要的目的层之 一。 通过对红井子地区长 9 油藏地质背景和油藏特征的研究，综合分析了沉积相、砂体展布、油气输导通 道及运移路径等。 结果表明：该地区长 9 油层组为典型的浅水三角洲沉积体系，整体以长 7 油层组生烃 有机质油源为主；长 7 烃源岩生成的油气以流体过剩压力为主要驱动力，从孔隙和裂缝运移至长 9 油层 组顶部构造并成藏；油源、通道和压差是控制该油层组油气成藏的主要因素

Upper Triassic Yanchang Formation in Ordos Basin is characterized by deep thickness of sedimentation and abundant oil and gas resources, which is one of the most important target zones for oil and gas exploration in the basin. According to the study of geologic background and reservoir characteristics of Chang 9 oil reservoir set in Hongjingzi area, this paper comprehensively analyzed the sedimentary facies, sand body distribution, hydrocarbon migration pathway and paths. The result shows that the Chang 9 oil reservoir set in the study area is typical shallow water delta sedimentary system, with Chang 7 organic material as the main oil sources. The excess fluid pressure is the main driving force for oil and gas generated by Chang 7 hydrocarbon source rocks, which migrated to the top structure of Chang 9 reservoir through the pores and fractures and accumulated. The main controlling factors of hydrocarbon accumulation are oil source, channel and pressure difference.