Complex Fracture Network In Shale Reservoir Based On Geomechanics Evaluation Index Study

China's shale gas exploration and development is in its infancy,and hydraulic fracturing is an important means to improve the efficiency of shale gas exploration and development.Before the hydraulic fracturing construction is performed,the complex fracture network formed after hydraulic fracturing in the fracturing block must be evaluated.The higher the evaluation index,the better the fracturing reform effect.At present,the related models of shale gas hydraulic fracturing complex fracture network evaluation indexes in China are still incomplete,resulting in inaccurate evaluation indexes and affecting shale gas exploration and development benefits.In this paper,after analyzing the main influencing factors of the shale gas reservoir fracturing effect in Changning area,based on geomechanics and big data analysis,the Ning 201 well was simulated and calculated using linear kernel function,50% cross validation,and machine learning SVM regression programming method.Complex fracture network evaluation index of shale gas reservoirs in this area.The research results show that the complex fracture network evaluation index is basically positively related to the amount of sand added: the higher the complex fracture network evaluation index,the better the fracturing reform effect.The evaluation index of the complex fracture network for the fracturing transformation of the shale gas reservoir in Well Ning 201 is divided into three levels:0.065-0.340,the fracturing transformation effect is poor;0.340-0.618,the fracturing transformation effect is moderate;0.618-0.900,fracturing The transformation effect is better.From the calculation results of the evaluation index model of complex fracture network in Well Ning 201 area,it is known that the fracturing effect of a few wells is general,and the fracturing effect of most wells is better,which is consistent with the actual situation.The prediction effect is more accurate.