DEEPLY PENETRATING GPR SURVEYS: EXPERIENCE OF KINEMATIC-DATA INTERPRETATION
O.A. Gulevich1, L.B. Volkomirskaya1, E.P. Kaygorodov2
1Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation, Russian Academy of Sciences, Moscow, Russia
2Shpilman Research and Analytical Center for the Rational Use of Subsoil, Tyumen, Russia
Keywords: REW CDP method (electromagnetic CDP), deeply penetrating GPR surveys, electrical resistivity, virtual borehole, velocity analysis
Abstract
Experimental studies were carried out in the permafrost zone using the method of reflected electromagnetic waves based on multi-offset data acquisition with common distance-point (REW CDP), referred to here for short as electromagnetic CDP (ECDP). Comparison of the results of processing several ECDP hodographs taken within the same site at a distance of up to 6 km, specifically, the vertical velocity distributions in the 0-10 μs time intercept reveals some similarities in the structure of permafrost and electrical properties of the underlying rocks, which agrees with the drilling data. The velocity analysis data served as the basis for the geophysical model of the CDP stacked section built as a 500 m deep “virtual borehole” with a step size of 50 ns (2-5 m), describing the change in the electrical resistivity parameter with depth.
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