Method and device for simulating full fracture length fracturing parameters of horizontal wells in unconventional oil and gas reservoirs

Abstract

The invention provides an unconventional oil and gas reservoir horizontal well section full-fracture-length fracturing parameter analog method and device. The method includes the steps of determining an unconventional oil and gas reservoir horizontal well section object region; obtaining three-dimensional earthquake prestack gathered data in the object region, conducting elastic parametric inversion and obtaining a three-dimensional space elastic parameter data body, wherein the three-dimensional space elastic parameter data body comprises a rock mass poisson ratio and Young modulus; calculating a rock mass brittleness index according to the rock mass poisson ratio and the Young modulus; establishing a rock mass mechanical parameter model based on three-dimensional grid nodes according to the three-dimensional space elastic parameter data body and the rock mass brittleness index; calculating stress information on the three-dimensional grid nodes, and generating a three-dimensional stress field distribution model; conducting full- fracture-length three-dimensional numerical simulation of fractures in the fracturing process according to the rock mass mechanical parameter model and the three-dimensional stress field distribution model. The unconventional oil and gas reservoir horizontal well section full-length-fracture fracturing parameter analog method and device can improve effectiveness and accuracy of unconventional oil and gas reservoir horizontal well section full-fracture-length fracturing parameter analog, and improve the reserve utilization degree of a reservoir stratum.

Description

technical field [0001] The invention relates to the technical field of oil and gas reservoir development, in particular to a method for simulating full-fracture-length fracturing parameters of horizontal wells in unconventional oil-gas reservoirs, and a device for simulating full-fracture-length fracturing parameters for horizontal wells in unconventional oil-gas reservoirs. Background technique [0002] Unconventional oil and gas reservoirs refer to oil and gas deposits whose characteristics, accumulation mechanism and exploitation technology are different from conventional oil and gas reservoirs. There are many types of unconventional oil and gas resources, generally including tight and ultra-tight sandstone oil and gas, shale oil and gas, super-heavy (heavy) oil, bituminous sandstone, coalbed methane, water-soluble gas, natural gas hydrate, etc. Among them, tight oil and gas (including tight sandstone oil and gas and tight carbonate rock oil and gas), shale oil and gas (i...

AI Technical Summary

Problems solved by technology

[0004] Taking the existing logging evaluation of tight sandstone oil reservoirs as a typical example of unconventional oil and gas reservoir logging, due to the complex logging response characteristics of tight sandstone reservoirs, high capillary bound water content, oil and water co-production after fracturing, reservoir fluid It is difficult to identify properties, and the calculation error of tight sandstone reservoir parameters is relatively large. Moreover, tight sandstone reservoirs have similar macroscopic physical properties, electrical properties, and oil-bearing characteristics, but have large differences in microscopic pore throat characteristics, and large differences in reservoir productivity levels. Some unconventional oil and gas reservoir logging methods have the following problems: tight reservoirs have poor physical properties, complex pore structure, strong heterogeneity, and difficult reservoir logging evaluation (including reservoir parameters, post-fracture water production and oil testing). The lower limit of the production layer corresponding to the method is determined, etc.)

[0005] Especially when multiple thin oil layers are developed in low-permeability reservoirs, conventional fracturing methods are difficult to meet the current stimulation needs. At the same time, with the deepening of development, the phenomenon of reservoir thinning becomes more serious, and the average drilling encounter of a single horizontal well The rate is reduced from 76% to 53%. If only the drilled layer is fractured, the reserves will be lost by about 43%.

At present, fracturing measures are all researched and applied under the assumption of uniform stress in the same layer and mechanical properties of rock mass, without considering the discontinuity, anisotropy, and inconsistency of in-situ stress directions of scattered sand bodies, and cannot adapt to Increasingly complex reservoir conditions and, due to a lack of in-depth knowledge of regional stress distributions, optimal matching of artificial fractures to sand bodies cannot be achieved

Images