Research On Geostress Prediction Method With Combining Logging And Seismic Data

The geostress is the driving force for the formation,migration and accumulation of oil.The specific stress field formed by different stress conditions directly controls the position where oil and gas may accumulate.The in-situ stress is closely related to the pressure prediction and wellbore stability.The stress field also determines the arrangement of the well pattern in waterflooding and the stimulation of fracturing.Because different lithology has different prediction methods to stress,this paper chooses the mudstone for the prediction of the ground stress,and establishes a method to predict the in-situ stress in the absence of the direct stress data.First of all,according to the core confining pressure experimental data of the rock mechanics parameters of the dynamic and static conversion,combined with previous studies of selected P-wave velocity and resistivity as stress parameters,and that the core confining pressure data is difficult to direct Stress prediction.Then,the appropriate conventional logging data are used to determine the shear strain in the shear wave velocity model and the combined spring empirical model.The effective stress and corresponding formation pressure are calculated.Finally,the tectonic strain and formation pressure are substituted into the seismic data to predict the ground stress.The method of geostress prediction usually needs more parameters.Due to the lack of direct stress data in conventional logging and seismic data,this paper selects the method with less parameters.Compared with the traditional method,it can be considered that the method we used is more suitable for the prediction of ground stress with seismic data.