Method for reducing inter-well crack interference in fracturing process

Abstract

The invention provides a method for reducing inter-well crack interference in the fracturing process. The method is suitable for a reservoir of which the porosity is smaller than 6% and the matrix permeability is smaller than 10<-4> mD and comprises the steps of temporary blocking, temporary blocking effect monitoring and microseismic monitoring in the drilling fracturing pumping process. The temporary blocking step comprises the substeps that 500-2,000 kg of solid particulates with the particle size of 109-212 micrometers, 70-120 kg of a temporary blocking agent with the particle size of 380-830 micrometers and 5-10 m<3> of fracturing liquid are mixed to form mixed liquid, the mixed liquid is pumped, and the displacement is controlled to be 10-15 m<3> / min. The temporary blocking effect monitoring step comprises the substeps that after the mixed liquid is pumped, slickwater is pumped, and it is judged that temporary blocking is achieved when it is monitored that the pressure at the wellhead generates positive pulse larger than 2 MPa. The microseismic monitoring step comprises the substeps that after it is judged that temporary blocking is achieved, whether crack steering is achieved or not is judged according to the trend of microseismic monitoring responding event points. The method has the advantages that hydraulic crack steering can be achieved, the reservoir recovery ratiocan be increased, and inter-well interference can be reduced.

Description

technical field [0001] The invention belongs to the technical field of oil and gas exploitation, and specifically relates to a method for reducing interwell fracture interference during fracturing. Background technique [0002] In order to meet the "factory" operation mode, the current shale gas development is generally developed in the platform mode, with an average of 6 to 8 wells per platform. This results in a very small well spacing, an average of only 200 to 300 meters. Therefore, interference between wells often occurs during fracturing operations, which seriously affects later production. [0003] In order to solve this problem, the following methods are usually used at present: 1. Perform fracturing simulation calculation in advance to predict the direction of fractures, as shown in CN201811536687.5, CN201611020378.3, etc.; 2. Control the scale of fracturing. Due to the limited knowledge of formation parameters in the former method, the simulation calculation resul...

AI Technical Summary

Problems solved by technology

Due to the limited knowledge of formation parameters in the former method, the simulation calculation results are very different from the actual situation; the latter method is difficult to control the scale of fracturing, and if the estimate is too high, it may lead to interwell interference. If the estimate is too low, it may lead to the failure of some formations to be stimulated, resulting in a low recovery rate of the reservoir

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