The Reservoir Characteristics And Forcasting Perspective Plays Of Yan 10 In Dingbian Area, Ordos Basin

Dingbian area is located in the northwestern of Shanbei Slope Belt, acrossTianhuan Syncline in Ordos Basin. Jurassic Yan'an Formation, as one of the main oillayer in this region, is small in size and relatively dispersed in distribution. Yan'anFormation was divided into 10 oil layers.Yan 10, with broad deposition, enjoys stabledistribution, with strong heterogeneity. In recent years, the exploration of Yan 10reservoir in Dingbian area had gone through a breakthrough. In order to clarify the oilbed distribution of Yan 10 reservoir, it is essential to apply research on the reservoircharacteristics and prediction on favorable zones.Taking sedimentary petrology, structural geology, petroleum geology, geologicallogging and other related subjects as theory foundation and using logging, drilling,logging, coring, geochemistry and other methods to do research on sedimentarycharacteristics, reservoir characteristics and accumulation factors, this papercomprehensive analysis controlling factors of reservoir and predicts favorable blocks.Obtain the following main achievements and know:(1)Using sign layer, cycle of sedimentation, lithology thickness contrast andother methods, Yan 10 is divided into two sand layer, and fine division and correlationstudies in etc stratigraphic framework.(2)Through observing cores, logging data and other related materialcomprehensive analysis, come to a conclusion that Yan 10 is braided riversedimentation, mainly development river filling, floodplains microfacies. Channelsand body is mainly showing a north-south extent band in plane. In some areas, riversin the event of mergers and branches form a braided or mesh patterns.(3)According to conventional thin core, cast, and mercury and other analysisdata, the reservoir of Yan 10 is mainly composed of litchis arkoses and arkose,and hasundergone compaction, pressolution, cementation and dissolution, The main pore is intergranular porosity and intergranular dissolution porosity. Heterogeneity isrelatively strong. Yan 10 is a reservoir bed which belongs to mid-porosity and lowpermeability.Based on the above research in comprehensive, combing controlling factors ofreservoir formation and the test of oil drilling, logging interpretation result, Predictedthree favorable blocks of classⅠand one of classⅡ. ClassⅠfavorable area in whichthe oil area of 35.24km2, geological reserves were 1241.5×104t, Shows the oil layer ofYan 10 in DingBian area has a good resource prospect.