The theoretical-empirical technique of hydrocarbons prediction in the boreholes logs with the basic parameter – compressibility

Abstract

The theoretical-empirical technique of hydrocarbon prediction in the boreholes logs is presented. It is based on the adequate physical-mathematical model of rocks, on the empirical relations between compressibility, porosity and pressure for these rocks, on the core data and also on acoustic logging data (the interval times or body wave’s velocities). For the cases of the acoustic logging data absence, the variants of the prediction technique by using data of gamma-logging, electric logging, and the offset logging method are developed. The presented technique is realized as a system of theoretical and empirical relations and the resulting functional. The adequate set of software tools is developed in the Fortran, C# and Excel environments. The technique is tested on the well’s data of a number of structures of Western oil and gas region of Ukraine: Lishchynska, Buchatska, Ludynska, Zaluzhanska, Zarichnianska, Nyklovytska, Orkhovytska. The statistical estimations of petrophysical characteristics of rock-collectors of those wells are presented. For more reliable prediction by the technique, instead of relations for the general parametric base, the empirical relations for concrete available in the studied boreholes logs types and subtypes of rock-collectors are elaborated.

Keywords

• borehole log
• porosity
• compressibility
• empirical relation
• acoustic logging
• predicting technique
• oil and gas saturation of rocks