Research on the Prediction of Fracturing Initiation Pressure for Horizontal Wells in Jimsar Shale Oil Reservoirs

Due to the sedimentary background of mixed three sources, the shale oil in Jimsar has complex lithology and obvious thin interbedded characteristics. In addition, the trajectory is adjusted multiple times during horizontal well drilling, resulting in strong reservoir heterogeneity. It is difficult to predict the fracture initiation pressure (FIP) during horizontal well fracturing, which cannot meet the needs of differentiated fracturing design for different reservoir sections of horizontal wells and affects the development effect of horizontal wells. This article establishes a prediction model for the fracture initiation pressure of various angles of the borehole wall considering the stress distribution of the surrounding rock, and calculates the frictional resistance along the way, static water pressure, and perforation frictional resistance. The bottomhole fracture initiation pressure is converted to the wellhead, and verified and corrected by actual horizontal well fracturing construction data. The prediction accuracy is high, proving that this method has high promotion value and provides a basis for optimizing the differentiated fracturing design of horizontal wells, achieving precise transformation of different reservoirs in shale oil horizontal wells, and ensuring the development effect of Jimsar shale oil.