SEISMIC CONVOLUTIONS IN THE QUATERNARY DEPOSITS OF LAKE SEVAN (Armenia)
A.M. Korzhenkov1, M.A. Avanesian2, E. Virgino3, A.S. Karakhanyan2
1O.Yu. Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, ul. Bol’shaya Gruzinskaya 10, Moscow, 123995, Russia
2Institute of Geological Sciences, National Academy of Sciences, 24a Baghramian Ave., Yerevan, 0019, Republic of Armenia
3Livermore National Laboratory, Ministry of Energy, Livermore, United States
Keywords: Seismic convolutions, seismites, lacustrine deposits, ancient earthquakes, Caucasus, Armenia, Lake Sevan
Abstract
The aim of the study is to detect deformations in the soft sediments in a tectonically active area (the Armenian Highland) and to examine the significance of the deformations as paleoseismicity indicators. Deformations in the form of pillows, pockets, sharp waves, and ovoids are exposed in the Sevan basin, within interbedded shallow lacustrine, beach, and fluvial sediments. Also, broken beds and low-amplitude thrusts are observed. Eight field criteria for assigning soft-sediment deformations to paleoseismic triggering provide strong evidence for the seismic origin of the deformations. According to the local relative stratigraphic scale, the Sevan seismites are of Pleistocene–Holocene age.
DOI: http://dx.doi.org/10.1016/j.rgg.2013.12.003
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