Ultra-deep sandstone fracture network transformation evaluating method based on heat-fluid-solid coupling effect

Abstract

The invention discloses an ultra-deep sandstone fracture network transformation evaluating method based on a heat-fluid-solid coupling effect. The ultra-deep sandstone fracture network transformationevaluating method comprises the following steps that physical parameters of a reservoir are obtained; distribution of fluid pressure in a fracture, the fracture length, the fracture width and the quantity of fluid filtered to the reservoir are calculated; reservoir pore pressure distribution after the unit discrete time is calculated; temperature distribution in the reservoir is calculated; stressdistribution after full coupling is calculated; the porosity and the permeability after the stress effect are solved through stress distribution; meanwhile, by combining the conversion relation of the stress to normal stress and shear stress of a natural fracture face, the force-bearing condition of the natural fracture face is obtained; and finally, whether the natural fracture is damaged or notand the kind of damage are analyzed. The ultra-deep sandstone fracture network transformation evaluating method is suitable for evaluating the fracturing transformation volume of an ultra-deep densesandstone gas reservoir fracture network, the blank aiming at numerical simulation study for evaluating the transformation volume of the ultra-deep dense sandstone gas reservoir fracture network is filled up, and a reliable prediction and evaluation method is provided for fracturing construction design of the ultra-deep dense sandstone reservoir fracture network.

Description

technical field [0001] The invention relates to an evaluation method for fracture network reformation of ultra-deep sandstone based on heat-fluid-solid coupling, and belongs to the technical field of oil and gas field development. Background technique [0002] By the end of 2018, natural gas production in the United States had reached 751.1 billion cubic meters, of which unconventional gas production accounted for 75%. However, China's natural gas volume still has a large gap compared with that of the United States. The development of ultra-deep unconventional tight gas is the key to increase and stabilize natural gas production in China. However, there are still many technical problems in the development of tight gas. Although natural fractures are well developed in ultra-deep tight gas sandstone reservoirs, natural fractures are difficult to activate due to factors such as deep gas reservoir burial depth, strong reservoir heterogeneity, high reservoir temperature, and hi...

AI Technical Summary

Problems solved by technology

[0005] So far, there is no fracture network volume stimulation evaluation model for ultra-deep tight sandstone reservoirs that considers the coupling effect of heat, fluid and solid.

Images