Prediction of Geomechanical Parameters Based on Anisotropic Rock Physics Model of Khadumites of the Eastern and Central Ciscaucasia

The khadumites of the Eastern and Central Ciscaucasia belong to unconventional anisotropic reservoir rocks of VTI symmetry. Because the rocks have extremely low permeability, hydraulic fracturing is commonly used to increase hydrocarbon production. To develop an appropriate design for hydraulic fracturing, knowledge of geomechanical characteristics is required, which includes two Young moduli and three Poisson ratios for the VTI medium. In this paper, we present correlations between the geomechanical characteristics and other parameters that can be measured at the log or seismic scale. The correlations are derived on the base of the rock physics model previously developed by the authors from log data available for a well penetrating these rocks. It is shown that the Young moduli correlate well with the acoustic impedance (a positive correlation). The Poisson ratio characterizing the vertical-to-horizontal strain exhibits a negative correlation with the shear impedance whereas the other two Poisson ratios characterizing the horizontal-to-vertical and horizontal-to-horizontal strain are rather stable within each suite but have certain values. A negative correlation between the kerogen content and the Young moduli is revealed for the Khadumsky suite that serves as a pay zone.