Dynamic inversion method for tight reservoir inter-well fracture aperture

Abstract

The invention discloses a dynamic inversion method for tight reservoir inter-well fracture aperture. The method comprises the following steps of acquiring an actual injection-production inter-well differential pressure curve according to dynamic production data of an injection-production well; according to the near well fracture network range of the injection well, the speed of fluid in an injection-production inter-well channeling distribution channel is determined; obtaining a theoretical injection-production inter-well differential pressure curve according to the speed of the fluid in the injection-production inter-well channeling distribution channel; according to the actual injection-production inter-well pressure difference curve and the theoretical injection-production inter-well pressure difference curve, the average permeability of the injection-production inter-well channeling distribution channel is determined; and according to the average permeability of the injection-production inter-well channeling distribution channel, the opening degree of the injection-production inter-well crack is determined. The method solves the problem that the crack identification predictioneffect is weak in the tight reservoir water injection development process due to the fact that an existing crack identification method cannot completely reflect the formation and disappearance processof the inter-well crack, the inversion cost of the tight reservoir inter-well crack opening degree is greatly reduced, inter-well crack opening degree information at different moments is provided, the accuracy of the tight reservoir inter-well crack opening degree inversion is improved, and tight reservoir development and management work is powerfully supported.

Description

technical field [0001] The invention relates to a dynamic inversion method for interwell fracture opening of tight reservoirs, belonging to the field of petroleum exploration and development. Background technique [0002] As domestic conventional oil reservoirs with medium and high permeability have successively entered high water cut periods, the efficient development of tight reservoirs plays an increasingly important role in the national energy security strategy. Hidden fractures often develop in tight reservoirs, which open after high-pressure fluid injection, thus forming a fracture network near the wellbore. Moreover, the fractures will continue to extend toward the production wells, forming channeling channels between injection and production wells, resulting in low-efficiency-ineffective circulation of injected water. [0003] At present, real-time quantitative research on fracture seepage capacity between injection and production wells has just started. Tight reser...

AI Technical Summary

Problems solved by technology

However, the above-mentioned technologies require many types of data, usually using seismic data, well logging, oil testing and dynamic data in the work area to establish a three-dimensional reservoir model. In addition to tracer monitoring technology, microseismic identification of reservoir fractures and geomechanics The technology of predicting reservoir fractures is easily affected by the test accuracy. The identification objects are mainly structural fractures, and the ability to identify fractures between injection and production wells caused by the opening of micro-fractures is weak. Therefore, the current tight reservoir fracture identification technology cannot accurately describe the fractures between injection and production wells formed by high-pressure water injection in injection wells, and thus cannot completely reflect the formation and disappearance process of fractures between injection and production wells, resulting in the fracture identification in tight reservoirs. Fracture identification is weak in the process of layer water injection development

[0004] Since the current fracture identification method has defects in identifying the fracture opening between injection and production wells in tight reservoirs, it is necessary to establish a method that can fully reflect the formation and disappearance of fractures between injection and production wells, and the equivalent opening of fractures between injection and production wells at different times. The dynamic inversion method is of great significance for timely determining the development degree of fractures between injection and production wells and designing corresponding control measures

Images