Study on catastrophe mechanism of hydraulic fracturing fracks initiation in radial boreholes

Radial drilling hydraulic fracturing has become a new stimulation method. The hydraulic fracturing effect of radial drilling on site is not ideal, and the stimulation effect of some wells is not obvious. The hydraulic fracturing effect of radial drilling is closely related to the crack initiation position after radial drilling fracturing. In the past researches on fracture initiation in radial drilling hydraulic fracturing, it is believed that the fracture initiation position is the radial drilling position and extends along the drilling direction. In this paper, a new model is established to solve the problem of hydraulic fracturing initiation mechanism in radial drilling. By studying the crustal stress analysis around radial drilling, it is found that when the parameters such as angle or crustal stress reach a certain degree, the initiation position appears near the wellhead. The occurrence of this mutation is the main reason for the unsatisfactory effect of hydraulic fracturing in radial drilling. The research results in this paper provide a reliable basis for radial drilling fracturing reconstruction of unconventional oil and gas reservoirs, and reference for the design of construction parameters of radial drilling.