Zones of decompaction of the Earth crust of the central part of the Ukrainian Shield (according to materials of petrophysical
and seismogravitational modeling)
© V.A. Korchin, P.A. Burtnyy, V.P. Kobolev, 2016
P-wave velocity and density of rocks depend considerably on temperature and pressure whose influence must be taken into
consideration in calculating these parameters at different depths. For the first time, this paper presents experimental data on
a P-wave velocity and density change for different rock types versus a change of temperature and pressure with depth.
Based on ther- mobaric, petrophysical and seismo-gravity modelling, a clarified cross-section of material composition has
been obtained for the area in the central part of the Ukrainian Shield. Local domains of decreasing rock density have been
revealed, which mostly coincide with the low velocity zone and are produced by deep thermobaric conditions. Such zones
of decreasing in material density can be served as one of diagnostic indicators in searching for deposits of mineral resources.
Key words: pressure, temperature, petrophysics, substance, model, zone of decompaction.