The Method of Evaluating Ground Stress Based on Cross Dipole Acoustic

Ground stress is one of the important parameters in the exploration and development of oil and gas reservoirs. Generally, the intuitive and accurate ground stress directions are obtained by electrical imaging and formation dip logging, while the ground stress direction given by array acoustic wave is difference from other methods for its being easily affected by the borehole and formation condition. In this paper, a method is proposed to improve the accuracy of judging the ground stress direction by acoustic wave through combining electrical imaging and acoustic anisotropy. The research shows that the direction of fast shear wave propagation and the direction of ground stress are intersected at a small angle in the developed layer with induced fractures, while the direction of fast shear wave in the undeveloped layer with induced fractures can represent the direction of maximum horizontal principal stress.