Permeability prediction method and system based on double media

Abstract

The invention provides a permeability prediction method and system based on double media. The permeability prediction method based on the double media comprises: obtaining data of a rock core under multiple historical overburden pressures, wherein each set of data comprises historical porosity and historical permeability; calculating each historical pore compression coefficient according to each historical overburden pressure and each historical porosity; determining adjustment parameters, matrix tortuosity fractal dimensions and fracture tortuosity fractal dimensions of the rock core according to each historical overburden pressure, each historical permeability and each historical pore compression coefficient; obtaining the current overburden pressure, the initial permeability, the current porosity, the current porosity variation and the current pressure variation; and predicting the current permeability according to the current porosity, the current porosity variable quantity, the current pressure variable quantity, the adjustment parameters, the matrix tortuosity fractal dimension, the fracture tortuosity fractal dimension, the initial permeability and the current overburden pressure so as to create or adjust an oil and gas field development scheme.

Description

technical field [0001] The invention relates to the field of oil and gas reservoirs, in particular to a method and system for predicting permeability based on dual media. Background technique [0002] Shale oil and gas is an unconventional oil and gas resource. The pore structure of shale reservoirs is very complex and the porosity is very low. In addition, there are often a large number of natural fractures in shale reservoirs, and the permeability of fractures is much higher than that of matrix. The main flow path for fluids. Stress sensitivity generally exists in tight oil and gas reservoirs and shale oil and gas reservoirs. Shale reservoirs have extremely low permeability, generally have nanoscale pores and natural bedding fractures, and have higher shale content than conventional sandstone. The compressive system is stronger, so stress sensitivity has a great influence on the productivity of shale oil and gas wells. [0003] The research on rock permeability in the pr...

AI Technical Summary

Problems solved by technology

[0003] The research on rock permeability in the prior art often assumes that the real core pores are a cluster of capillary bundles, and studies the influence of pressure changes on permeability from the mechanical properties of the rock, for example, the rock skeleton of the real core is assumed to be a cluster of capillary bundles. Capillary and conforming to fractal distribution, or assuming the rock skeleton as cubic fractures, these two methods are too idealized, which are very different from the actual pore and fracture network, and cannot accurately predict the permeability of shale reservoirs under different pressures, which is not conducive to Reservoir development

Images