VERTICAL PERMEABILITY EFFECT ON TERRIGENEOUS OIL FIELD RESERVOIR ADAPTATION

Abstract

The relevance of the research lies in the need to create an algorithm for calculating permeability in three-dimensional space using geological and geophysical data. At this stage, the horizontal distribution of permeability should be taken into account. And the vertical permeability is usually set by the ratio of the permeability in the horizontal plane and the decreasing or increasing coefficient. In fact, in this case, the spatial change in the vertical component of the permeability along the section is not taken into account. This happens for two reasons: a small number of studies of vertical permeability and, accordingly, the absence of equations for calculating this very important parameter. This is a global problem of lack of initial information when examining actual core material. And the core material is the basis for studying the anisotropic characteristics of rocks. Permeability, in its turn, is the most important reservoir characteristic and affects the ability to extract hydrocarbons from reservoir strata. The aim of this work is to form a dependence of vertical permeability on porosity, the distribution of permeability in the geological and hydrodynamic model, check the quality of adaptation of production and injection data. The study object is a field with a terrigenous reservoir type. In this field, calculations of the anisotropy of horizontal permeability have already been carried out, and within the framework of this study, calculations of the vertical permeability were carried out and its influence on the adaptation of the field was taken into account. A feature of this field is the variability of the direction of the improved permeability zones, as well as the presence of laboratory core studies of the vertical permeability of reservoirs. Such studies will allow determining the vertical permeability of rocks and calculating the vertical distribution of the section. The studied formations are represented by Upper Jurassic deposits with a non-uniform distribution of filtration and reservoir properties. Methods: plotting the dependence of vertical permeability on porosity based on core studies, introducing the vertical component of permeability into geological and hydrodynamic models, calculating the adaptation of actual production data after taking into account the vertical component of permeability. As a result of the study, the petrophysical model of the studied field was refined, it turned out to achieve a more accurate distribution of petrophysical properties in the geological model. Thus, it becomes possible to take into account the real features of the geological structure, hence all three components of the permeability vector are used. One of the main points is the creation of a model that describes the distribution of properties as accurately as possible and reflects the real characteristics of production. Carrying out the most accurate forecast and planning the application of enhanced oil recovery methods. A huge amount of accumulated data makes it possible to create correlations between various petrophysical parameters. It is necessary to supplement and develop a database, which in the near future can serve as a storage for analogous fields that do not have the data to create their own similar dependencies.

Keywords

• permeability anisotropy
• anisotropy scale
• vertical anisotropy
• hydrodynamic simulation
• petrophysical calculations