Mechanism of Fracture Extension Near Borehole Wall in Deviated Well and Fracturing Technology

With an increase in well angle, difficulties in fracturing the well is also increasing. The problems encountered in fracturing high well angle wells are low sand concentration, higher pressure, and difficulties in adding proppants into the fracturing fluid in mid- and later-stage of the fracturing job. The fracturing jobs most often fail the design. It has been understood that the main reason for the difficulties in adding proppants is the deviation of the well. Using a large size true tri-axial simulator, the extension of fractures at different downhole conditions were studied. And combining the test results with field operations, the main reason of difficulties in adding proppants into fracturing fluid in mid-or later-stage of fracturing in the deviated wells in the A-fault in Nanpu can be ascertained. Measures to deal with the difficulties have been established, and field operations have been successful, because the concentration of proppants has been increased from 18% to 40%.