Abstract：The Chang 8 interval of the Upper Triassic Yanchang Formation is a typical low-porosity and low-permeability reservoir in Jiyuan area of the Ordos Basin.Researches of the main controlling factors，the formation conditions of high quality reservoirs and forecast of the favorable target have great significance for the exploration of potential oil and gas resources.Comprehensive analyses have been made on the sedimentary characteristics，property characteristics，rock thin sections，casting thin sections and so on.This paper discusses the distribution of favorable reservoir，the petrology characteristics，the pore texture and pore types，the physical property and the diagenesis types，which finally makes a comprehensive prediction of the distribution characteristics of favorable reservoir area.The results reflect that the lithic arkose is developed well and the cement，especially the ferrocalcite，is general in the Chang 8 interval of the study area.It is poor of the physical properties of the whole reservoir which is characterized by strong heterogeneity.The pore types mainly include residual intergranular pore and dissolution pore.The reservoir is controlled by the sedimentation，diagenisis and tectonism.Based on the above analyses，we forecasted the favorable reservoir in the Jiyuan area.
. Favorable reservoir distribution and its controlling factors of the Chang 8 interval of Upper Triassic Yanchang Formation in Jiyuan area，Ordos Basin[J]. JOPC, 2012, 14(3): 285-294.
