Research On Stress Field Modeling Method Based On Geophysical Multi-source Information

With the continuous development and progress of petroleum exploration and development technology,the main purpose of exploration and development has gradually shifted from discovering new large oil and gas fields to increasing the output of existing oil fields,and using new technologies to exploit oil and gas reservoirs that are difficult to exploit in the early stage of oil field development.The design of stimulation construction schemes such as drilling and fracturing based on the evaluation of the in-situ stress field is particularly important for the stimulation in the later stage of oilfield development.Therefore,the development of the three-dimensional modeling method has practical guiding significance for the study of stress evaluation in the study area.In the early stage of exploration and development,providing a geophysical modeling method that uses geophysical multi-source information to make up for part of the missing data will help to gain an overall understanding of the development target.In order to clarify the geomechanics and rock mechanics characteristics of the work area,firstly,based on the weighted average idea,a shear wave prediction model based on multiple regression was established by using a few dipole sonic logging data in the work area combined with density and neutron logging data;the estimated model was estimated from this The shear wave time difference of the remaining wells in the work area was analyzed,and the in-situ stress profile of a single well was analyzed;then,fine stratigraphic division and three-dimensional geological modeling were carried out through logging data,layered data,and seismic data;finally,the calculation results of rock mechanics parameters Carry out interpolation modeling,complete the in-situ stress field modeling and rock mechanics parameter modeling in the work area.And through the anisotropy analysis of dipole shear-wave logging data and the analysis of micro seismic events in cross-well micro seismic monitoring,the horizontal principal stress direction of the layer is determined.The time difference prediction results are in good agreement with the on-site sonic dipole sonic logging time difference results,and the error between the calculation results of the in-situ stress field profile and the core mechanics test results is within a reasonable range.The modeling results show that the physical parameters of the formation in the work area are good,the maximum principal stress is mainly distributed in 30-34MPa,the minimum principal stress is mainly distributed in 27-29MPa,and the formation is controlled by reverse faults.The direction of the maximum horizontal principal stress is about 50°-55°east by north,and the direction of the minimum principal stress is about40°west by north.In this study,in the case of less dipole acoustic construction,the improved shear wave prediction model was used to obtain the shear wave velocity to complete the characterization of the in-situ stress field.It provides guidance for geostress and rock mechanics parameters for drilling planning and fracturing design in the work area.After fracturing,the newly drilled experimental horizontal well has a reservoir reconstruction volume of 1027.1×10~4m~3.After 120 days of production,the cumulative oil production was 1807.65t,realizing the effective development of the reservoir.