Well Test Analysis Of Halahatang Fracture-cavity Carbonate Reservoir

With the improvement of energy source exploitation technology and human's increasing demands,unconventional energy has received more and more attention.Fracture-vuggy carbo nate reservoir becomes the focus of each country because of its huge reserve and high product ivity.Different from conventional sandstone reservoir,fracture-vuggy carbonate reservoir is c haracterized by strong heterogeneity and unusual reservoir space.Due to that the matrix is inc apable of storing oil,effective reservoir space usually concentrates in corrosion cavity,fractur e and large cave.Therefore,well testing methods of conventional sandstone and fractured car bonate reservoir don't apply to fractured-vuggy carbonate reservoir.In view of the limitations of the available well test methods,this paper makes a well test research on fractured-vuggy reservoir in Halahatang oilfield.Base on reservoir characteristics study of fractured-vuggy carbonate reservoir,methods of poromechanics,reservoir engineerin g and numerical well test are adopted to classify fractured-vuggy reservoirs.There're totally f our large categories(fracture-vuggy,cavern,fractured and inter-well interference type)includi ng twelve subgroups of fractured-vuggy reservoir types.Then,the following studies are carrie d out.(1)After analyzing and summarizing geological,seismical,well drilling,logging and wel 1 test data and single well production performance of the twelve reservoir types,well test inter pretation curves of each reservoir type are plotted and then compared with field well test curv es.(2)Analytical well test method is applied to interprete well test data of fractured-vuggy c arbonate reservoir of Halahatang oilfield comprehensively,and its limitations and problems ar e presented;that is to say,analytical well test method doesn't apply to fractured-vuggy reserv oir.(3)Numerical well test and all pressure history fitting analysis method are proposed to a nalyze testing data of fractured-vuggy carbonate reservoir in Halakhatan.And the interpretatio n results are consistent with production performance,which proves the advantages of numeric al well test in dealing with well test problems of fractured-vuggy reservoir.In this paper,a set of numerical well test technological process and method for fractured-vuggy reservoir is put forward,which is of significance in guiding well test and production pe rformance analysis of fractured-vuggy reservoir.