Method for acquiring three-dimensional permeability fields of netted fracture-cave oil reservoirs

Abstract

The invention discloses a method for acquiring three-dimensional permeability fields of netted fracture-cave oil reservoirs. The method includes: establishing a three-dimensional porosity field of a netted oil reservoir, and determining quantitative relation between porosity and permeability of the oil reservoir; acquiring equivalent permeability of flat and tubular fractures and caves, determining the minimal critical permeability value, subjecting the permeability of the minimal critical permeability value to truncation processing by taking the critical permeability value as the maximal value so as to obtain an equivalent permeability value; correcting the permeability field subjected to the truncation processing with a tracer agent and an interference testing result; correcting the permeability field by the aid of the numerical simulation method. The permeability acquired plays a decisive role in knowing oil reservoir developing rules, predicting oil reservoir yield, optimizing and adjusting production layers, optimizing and adjusting well patterns and well spacing, researching residual oil exploiting rules, profile controlling and water blocking, formulating gas injection and water injection schemes, exploiting cost of the oil reservoirs is reduced, exploiting efficiency of the oil reservoirs is improved, and the purpose of increasing economic benefit of oil reservoir exploiting is achieved.

Description

technical field [0001] The invention belongs to the technical field of network fracture-cavity oil reservoir exploitation, and relates to a method for obtaining a three-dimensional permeability field of network fracture-cavity oil reservoirs, so as to improve the pertinence and rationality of oil reservoir development, and ultimately improve oil reservoir recovery. Yield, and reduce the cost of oil reservoir extraction. Background technique [0002] Permeability is a parameter that reflects the allowable fluid passage capacity of the reservoir. It is the basic data for evaluating reservoir permeability, calculating oil well productivity, evaluating reservoir permeability, predicting oil and gas well productivity, and reservoir development methods. The permeability parameter is very important, and its importance runs through the entire development history of oil and gas reservoirs, and is reflected in every development link. The importance of the test fee for obtaining the p...

AI Technical Summary

Problems solved by technology

These characteristics of fracture-cavity reservoirs make it very difficult to predict the physical properties between wells

Nevertheless, after years of technological development and accumulation, such as the application of well-seismic joint inversion technology, multi-point statistical prediction technology, multi-wave and multi-component seismic attribute analysis technology, multi-disciplinary collaboration of geology and development, the porosity data obtained are basically It can meet the needs of reservoir operation and management, but the accuracy of permeability is still extremely low, and the permeability value of many areas can only be estimated out of thin air

There are two main reasons: (1) It is difficult to predict the permeability of large-scale fractures and caves. Firstly, it is impossible to know the shape of underground fracture-cave bodies clearly, and a slight change in shape can lead to a large change in permeability parameters; secondly, The flow law of fluid in large-scale fracture-cave bodies follows the law of free fluid flow and pipe flow. Even if the shape is clear, if the shape is irregular, the corresponding permeability value cannot be obtained theoretically. Even if the concept of equivalent permeability is adopted, the The permeability value of is also a variable value

Even if the concept of equivalent permeability is adopted, the obtained permeability is not a fixed value, but also related to flow velocity and flow state; (2) The permeability value is affected by various geological factors, and is very sensitive to changes in these factors. Therefore, the establishment of the three-dimensional permeability field of the whole reservoir is a common technical problem faced by all heterogeneous reservoirs, and the heterogeneity of network reservoirs is far beyond that of general types of reservoirs. rate prediction is more difficult

At present, there is no reasonable and applicable method at home and abroad to obtain a reliable 3D permeability field for this type of reservoir.

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