Modeling method of stress-sensitive damage oil and gas reservoir, 4d quantitative and intelligent diagnosis method and system of temporal and spatial evolution of damage degree

Abstract

The invention relates to the technical field of oilfield exploration, and discloses a modeling method for stress-sensitive damage reservoirs, a method for determining the damage degree of the reservoirs, and a system thereof. The modeling method includes: determining the effective stress of the reservoir in the preset area of ​​the well to be diagnosed; according to the pore size distribution characteristics of pores of the reservoir, each capillary bundle of the reservoir under the effective stress determine the flow rate of the fluid in the reservoir, wherein the capillary bundle is composed of a plurality of solid matrices and pores between the plurality of solid matrices; and according to the reservoir The permeability model of the layer and the flow rate of the fluid in the reservoir, determine the spatiotemporal evolution simulation equation of the stress sensitive damage reservoir. The invention can quantitatively simulate the four-dimensional space-time evolution process of reservoir damage characteristics caused by stress sensitivity, so as to carry out quantitative prediction of reservoir damage and space-time deduction of damage law for wells without reservoir damage.

Description

technical field [0001] The invention relates to the technical field of oilfield exploration, in particular to a modeling method and system for stress-sensitive damage reservoirs and a method and system for determining the damage degree of the reservoirs. Background technique [0002] In each period of oilfield exploration and development, due to the influence of various internal and external factors, the original physical, chemical, thermodynamic and hydrodynamic equilibrium state of the reservoir will change, which inevitably causes the reservoir near the wellbore wall and even far from the wellbore wall. The internal permeability of the reservoir decreases, blocking fluid flow, causing reservoir damage and well production decline, and even "shooting" the reservoir. The causes of reservoir damage are various and complex, especially during the production process, the reservoir rock storage and seepage space, surface wettability, hydrodynamic field, temperature field, rock ty...

AI Technical Summary

Problems solved by technology

The core flow test method is to understand the degree of damage through the change of permeability before and after core displacement. Although it is more suitable for studying single-factor reservoir damage, it is difficult to reflect the law of reservoir damage on a large scale

In addition, due to the ideal conditions of the indoor core experiment, the cores used for evaluation are all original state cores, and the dynamic changes of reservoir properties cannot be considered, so the experimental results are quite different from the real damage of the downhole reservoir.

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