Tectonophysical Forecasting Criteria of Vein Bodies Thicknesses in Deep Horizons of the Nadvigovaya Zone, Badran Ore Field, Republic of Sakha (Yakutia)

A new technology of stress inversions is proposed on the basis of data of mute fracturing with measured amplitudes of dilative opening of fractures (tension shear), which are registered by mineralization (vein bodies). The involvement of a basic law of geomechanics of supercritical deformation, which determines the interrelation between amplitudes of shear deformations and deformations of transverse extension (dilatancy), allows us to link the amplitudes of opening of shear fractures with the level of Coulomb stresses. This approach can be used for a conjugated fracture system and fault zones with a system of similarly oriented fractures. Our algorithm and technology of stress calculation consist of consecutive analysis of a geometrical form and characteristic lineaments of density zone of fracture poles on the stereospheres and stress conditions of these fractures on Mohr’s diagram. The algorithm allows the calculation of the parameters of stress tensor both on the basis of graphical analysis on the stereonets and Mohr’s diagram and using a group of formulas. The algorithm is applied for the Nadvigovaya zone of the Badran deposit. The stress values are calculated for a fault area with measured fracturing, and a forecast for promising areas is given for a deeper fault part in areas with possible most intense dilatancy of fracture flow.