NUMERICAL SIMULATION ON THE QUANTITATIVE PREDICTION OF STRUCTURAL FRACTURES IN MULTI-LAYER LOW PERMEABILITY SANDSTONE RESERVOIRS

摘要

This study explores the quantitative prediction method for structural fractures in low permeability sandstone reservoirs,taking the Fuyu low-permeability reservoirs of the Putaohua oilfield in the Daqing placanticline as the research object.The quantitative relationship between stress fields and fractures has been established according to the related theory of elastic mechanics and fracture mechanics.The results show that the strike of the tensional fractures in Fuyu oil reservoir is NNW and NNE,and that of the shear fractures is NWW and NNE.The main fracture initiation period was the end of Qingshankou age.The distribution of fracture permeability is between 0.1-30mD,with vertical permeability being the largest,and the north-south permeability of fractures being less than the east-west permeability.Permeability in the northern part is large; permeability in the southern part is small,and fracture permeability is large in areas adjacent to faults.