Research And Application Of Fracturing Technology For Large Slope Wells In The Beach

Curently, unconventional reservoirs have became the research hotspots duo to the development of oil and gas exploration technology. The fracturing technology of highly deviated wells plays an important role in improving the single well control area and recovery in unconventional reservoirs. However, the lack of reservoir protection technology during hydraulic fracturing and the complicated hydraulic fracture initiation and propagation machanics in highly deviated wells largely delays the development of these reservoirs.The exploration chanllenges of Nanpu oilfield have been clearified besed on the analyses of reservoir mineral content, reservoir sensitivity and heterogeneity. In this paper, fracturing fluid additive is selected for reservoir sensitivity and fracturing fluid system. The compatibility of fracturing fluid with reservoir fluid and rock and the performance of fracturing fluid are evaluated and evaluated. In the aspect of crack propagation mechanism of large inclined shaft, the effect of different azimuth angle, phase angle and plane stress difference on fracture initiation of hydraulic fracturing in inclined well is studied by true triaxial experiment. And the crack propagation pattern and distortions of near well fracture, combined with the site of the construction of fracturing wells, have been fractured to determine the shape of wells. In the aspect of enhancing the pertinence of fracturing, this paper studies the perforation technology, stratified fracturing technology and fracturing technology of large inclined shaft, and forms a set of fine stratified fracturing technology for high inclination well. The accuracy of reservoir reconstruction is improved, the utilization degree of reservoir reserves is improved, and the expected effect of effective period of fracturing well is prolonged. Finally, the research results are verified and analyzed by field examples.A medium-high temperature guanidine gel fracturing fluid system with strong comprehensive performance, wide application range, low residue, low damage, easy to break and easy operation has been developed. The results of fracturing simulation show that the larger the net pressure is, the smaller the angle between the fracture direction and the horizontal maximum principal stress is, and the more the crack extension surface is. When the deviation angle is less than 20° or greater than 80°, the degree of distortion is small and the secondary seam is less. When the deviation angle of the well is 30～60°, the degree of distortion is large, the secondary seam is complex and the fracture shape is complex. The larger the angle between the borehole orientation and the horizontal maximum principal stress is, the higher the irregularity of the crack is, and the more the curved surface and the secondary seam are. The stress difference is small, the initiation pressure is high, the initiation point is many, the secondary fracture is easy to form, and the fracture shape is complicated. A set of fine stratified fracturing techniques for high gradient wells was developed by segmented parameter design and fracturing technology optimization. The results obtained in the field application has achieved good results, for the same type of deep inclined reservoir of low-permeability reservoir to provide economic and effective development of guiding significance.