APPLICATION OF ROCK GEOELECTRIC PARAMETER GRADIENT BASED ON NEAR-FIELD TRANSIENT ELECTROMAGNETIC SOUNDING DATA TO PREDICT BRINE-SATURATED OVERPRESSURED ZONES IN CARBONATE INTRASALT RESERVOIRS IN THE SECTION OF LOWER CAMBRIAN RESERVOIRS OF THE SOUTH OF THE SIBERIAN PLATFORM
Purpose. The article deals with the forecasting method of brine-saturated zones with the abnormally high formation pressure (AHFP) in intrasalt carbonate reservoirs in the section of the lower Cambrian of the South of the Siberian platform according to the data of the near-field transient electromagnetic sounding. Methods. The method of near-field transient electromagnetic (TEM) sounding is used to determine the resistivity and conductivity of rocks composing the section. Results. Comparison of the results of prospect and exploration well drilling and the results of near-field transient electromagnetic sounding shows that the lateral gradient of geoelectric parameters allows to delineate potentially dangerous brine-saturated zones. Conclusions. The maps of longitudinal conductivity/resistivity as well as the maps of the resistivity/conductivity gradient of Belskaya suite of the lower Cambrian have been compiled. The criteria for the identification of gradient zones associated with the intrasalt carbonate brine-saturated reservoirs collectors have been determined.