Reservoir Characteristics And The Prediction Of Prospecting Area Of Buried Hills In De2 Block In Beier Depression

Beier Depression has always been one of the important hydrocarbon exploration regions in the Hailaer Basin.With the progress of hydrocarbon exploration of buried hills and the difficulty of conventional oil exploration,explorationist and geologists are focusing on the hydrocarbon-exploration of buried hills.The study area is located in the Beier Depression,with an area of 246 km².Based on the geological background,combined with well-logging and seismic data,this paper conducted research on the reservoir characteristics of buried hills in De2 block.We focus on the characteristics of bedrock,fractures,reservoir types and influencing factors.We precisely predict the distribution of fractures and beneficial reservoir zones.The bedrock in De2 block are mainly slightly metamorphosed sandstone-mudstone,lithic feldspathic sandstones and volcano clastic rock.The reservoir in De2 Block is poor and the porosity and permeability change drastically,the value of porosity is vary from0.1%to 14.3%,whereas mainly distributed between 2%and 8%.The average porosity is4.2%,which belongs to low porosity.Permeability is changing from 0.01md to 6.1md,the average permeability is 0.25?10^-3um² and mostly below 1?10^-3um²,which belongs to low permeability.In conclusion,the studied area has low porosity and permeability reservoir.There are many micro-fracture and dissolved pore because the bedrock in central and southern have suffered the tectogenesis,weathering,leaching and erosion.The distribution of reservoir has strong heterogeneity.The fractures in De2 block with effective cracks distributed between 50°and 90°are relatively developed.The direction of fractures is mostly north-east and earth-west direction and cracks are mainly small seams.After we predict the fracture distribution in target block by using geology and well logging data,optimizing the seismic attributes of known area.Thus,we divide the reservoir into two types:the I type reservoir is mainly in central,meanwhile the II type reservoir is mainly in northern of the block of buried hills.The hydrocarbon is well shown by the drilled wells in the study area,consistent with predicting.Therefore,these methods provide reference and guidance for the further prediction of prospecting fractural reservoir.