METHOD FOR DETERMINING WIDTH AND RELAXATION CHARACTERISTICS OF TECTONIC DISCONTINUITY ZONE Russian patent published in 1997 - IPC

FIELD: engineering-geological study of rock mass structure; surveying for construction of land and underground structures; construction of models and schemes of block structure and tectonic discontinuities; diagnostics of the mechanical state of rock masses during operation of structures and exploitation of minerals. SUBSTANCE: pulsed wave-type vibrations (PWV) are detected by geophones placed on a profile across a tectonic discontinuity zone at intervals such that at least one geophone is within this zone. Vibration propagation velocity between every pair of neighboring registration stations and PWV power spectral density for each station are determined. Width of the tectonic discontinuity zone is identified with the width of a zone wherein the elastic vibration velocity (C) decreases by a ≥ 3 as compared with that beyond the tectonic discontinuity zone, where a is the mean-root-square error in determining C. Relaxation characteristics, such as stress relaxation time T1 at constant strain, shearing strain relaxation time T2 at constant shearing stress, compressive stress relaxation time T3 at constant cubic strain, and strain relaxation time T4 at constant average pressure, are determined from the PWV power spectral density obtained for the tectonic discontinuity zone and beyond this zone by modelling and using Burgers body to approximate the tectonic discontinuity. EFFECT: higher efficiency. 3 dwg