Geological controls in the geostatistical simulation of hydrocarbon reservoirs

Abstract EN

In many, if not most, reservoirs geological structures have an overriding and controlling effect on the continuity and heterogeneity of petrophysical variables.

In general terms, categorical variables influence the variability of quantitative variables.

As this influence is significant, and sometimes dominant, it is essential that it be incorporated either explicitly or implicitly in reservoir models.

This paper describes a method of incorporating categorical control variables, such as lithology, in the geostatistical simulation of quantitative variables, such as porosity and permeability.

The method described is basically a co-conditional co¬simulation version of sequential gaussian simulation using a truncated gaussian distribution to model the category variable(s).

The method is applied to the simulation of porosities in carbonate rock in which lithology has a controlling influence on the spatial distribution of porosities.