DEEP STRUCTURE AND MARGINS OF THE KURAI BASIN (Gorny Altai), FROM CONTROLLED-SOURCE RESISTIVITY DATA N.N. Nevedrova, E.V. Deev, and A.M. Sanchaa
N.N. Nevedrova1,2, E.V. Deev1,2, A.M. Sanchaa1
1A.A. Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Koptyuga 3, Novosibirsk, 630090, Russia 2Novosibirsk State University, ul. Pirogova 2, Novosibirsk, 630090, Russia
Keywords: Neotectonics, resistivity surveys, TEM, VES, Kurai basin, Gorny Altai
Abstract
According to the data processing results, the basin is the deepest along its northern, southern, and eastern margins. The sedimentary fill comprises two resistivity units corresponding to two sequences deposited at different stages of the basin history. The lower, less resistive unit consists of Paleogene–Neogene lacustrine clay and the higher-resistivity upper unit represents coarser Quaternary deposits. In Paleogene–Neogene time, the basin formed by the left-lateral pull-apart mechanism. The earliest Quaternary strike-slip faulting in the setting of overall compression produced the Central Kurai basin within the northern Kurai basin, while the flanking ranges and fault blocks thrust upon the basin transforming it into a ramp. Thus, piedmont steps rose along the basin margins, and the marginal grabens became ramps and half-ramps.
DOI: http://dx.doi.org/10.1016/j.rgg.2013.12.008
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