Acoustic Emission Crustal Stress Experiment Based on Borehole Wall Electrical Imaging

Core orientation parameters is calculated by using the electrical imaging data of borehole wall, and the sampling and calculation methods of acoustic emission experiments are optimized to obtain the crustal stress. It provides support for geological risk identification, well structure design, and drilling fluid density window in complex ultra-deep formation drilling. The coordinate transformation model is established to calculate the formation structure, elliptical hole and the geographical position of induced fracture. The three-dimensional in-situ stress of complex ultra-deep strata is calculated by figuring out the location of drilling core and principal stress, optimizing the preparation of acoustic emission rock sample and calculating horizontal stress, and collecting acoustic emission signals of rock sample experimentally. Depending on the rotation of coordinate system, the borehole wall image with geographical orientation is formed. The borehole imaging identification geographic orientation chart is established. Using the chart to determine the core geographical orientation, so as to get the location of the core orientation. Based on core orientation and current principal stress orientation, acoustic emission experiments are designed to reduce the difficulty of experiments and improve the accuracy of experiments. The experimental method is applied to the complex ultra-deep formation, and the three-dimensional stress and azimuthal data are obtained, which provides technical support for the optimal and rapid drilling. This research result is of great significance for the application of borehole imaging logging data, geographical orientation identification of drilling coring, optimization of acoustic emission in-situ stress experiment and geological risk identification of complex ultra-deep drilling.