S.N. KASHUBIN, O.V. PETROV, T.M. YAVAROVA, I.YU. VINOKUROV,
N.A. KRUPNOVA (VSEGEI), T.S. SAKOULINA (Sevmorgeo)
Low-velocity layer in the sedimentary section of the North Chukchi Trough: seismic data and possible geological models
Low-velocity layer recorded from discontinuities in head wave arrival-time curves and the appearance of the “shadow zone” has been identified in the section of the North Chukchi Trough sedimentary cover based on results of deep seismic soundings (DSS). According to data of mathematical modeling of DSS wave fields and their comparison with materials of the CDP seismic reflection, plausible velocity and geological models of the North Chukchi Trough sedimentary basin have been proposed, which explain this peculiar feature of the section. As the most plausible model for the formation of such a thick sedimentary basin in the North Chukchi Trough, the “basin in the basin” model is assumed, when provenance areas were alternately as follows: in the Mesozoic time, the area of the Central Arctic uplifts, and after its subsidence to bathyal depths in the Cenozoic, the Wrangel-Herald Arch.
Keywords: North Chukchi Trough, sedimentary basin, wideangle and reflection seismics, low-velocity layer.