METHOD OF ACCOUNTING DIFFERENT SOURCES FOR PERMEABILITY ESTIMATION UNDER LACK OF GEOLOGICAL AND FIELD INFORMATION

Abstract

The relevance of the work is associated with the depletion and long-term development of existing fields, while the study of poorly explored areas of promising oil and gas content is of particular importance. Often, companies in the oil and gas industry meet the problems in assessing potential sites in the face of a clear lack of geological information. The main aim of the research is prediction of the reservoir permeability – one of the most important parameters influencing the prediction of further development while it is often the most difficult to determine, especially in the absence of field research and development, or due to existing contradictions in the field data. Methods. The paper presents the accurate method for accounting and systematization of the available information on permeability estimation with the simultaneous use of two tools – the well-known probabilistic approach to estimating reserves (P10/50/90), as well as the one with the use of terziles. The combination of these approaches allows one to take into account the permeability obtained from different sources – for example, from the well test together with data obtained in the petrophysical model. It is well known, in cases of complex reservoirs, data from different sources may contradict each other. Results. The specified algorithm allows integrating the data on the permeability of reservoirs, including the data determined not sufficiently reliably, without significantly going into the reasons for such discrepancies. At the same time, an essential condition for applying the method is the presence of a statistically significant amount of data, which can be taken into account by using information on neighboring fields and adjacent areas. It also seems possible to generalize the method to the determination of some other geological parameters.

Keywords

• oil
• permeability
• well
• reserves
• forecast
• probability
• data
• welltest
• petrophysical model