Preparation method of unconventional natural gas well fracturing physical simulation sample

Abstract

The invention provides a preparation method of an unconventional natural gas well fracturing physical simulation sample, which comprises the following steps: 1, determining the uniaxial compressive strength and tensile strength of a reservoir shale test piece, and selecting cement satisfying the strength grade requirements; 2, placing two sandstone sheets on the two sides of a concrete mold, and pouring the stirred mixture of the cement, the quartz sand, the stones and the water between the two sandstone sheets; 3, removing the mold after curing and molding to obtain a simulated multi-layer sample, and performing bedding surface shear strength test on the sample to determine the shear strength; and 4, drilling a simulated borehole in the center of the sandstone thin plate, and cementing the simulated wellbore to obtain the multi-layer sample with the simulated wellbore. The unconventional natural gas well fracturing physical simulation sample is prepared by combining the blended similar material and the natural sandstone, the fracturing test piece more conforming to the unconventional natural gas condition is prepared, and the expansion mechanism of cracks in the direction perpendicular to the bedding direction in the unconventional natural gas well fracturing process can be more deeply studied.

Description

technical field [0001] The invention belongs to the technical field of rock sample preparation, in particular to a method for preparing an unconventional natural gas well fracturing physical simulation sample, which is suitable for the fracturing physical simulation of tight gas and shale gas in unconventional natural gas. Background technique [0002] At present, my country's proven and developed unconventional natural gas resources mainly include tight gas, shale gas, coalbed methane, etc., and are mainly distributed on land in Ordos, Sichuan, Songliao, Bohai Bay, Junggar, Qinshui, etc. basin. my country's unconventional natural gas has a resource base for large-scale development, with remarkable exploration results and important progress in development. In the past ten years, the proven reserves of unconventional natural gas have grown rapidly. Among the cumulative proven geological reserves of natural gas, unconventional natural gas accounts for about 41%, and it shows a...

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