PREHISTORIC EARTHQUAKES AND FAULT SCARPS IN THE BARGUZIN FAULT ZONE ( Baikal Rift system )
A.V. Chipizubov, S.G. Arzhannikov, R.M. Semenov, O.P. Smekalin
Institute of the Earth's Crust, Siberian Branch of the RAS, 128 ul. Lermontova, Irkutsk, 664033, Russia
Keywords: Paleoseismology; multiple fault scarps; dating fault scarps; magnitudes of prehistoric earthquakes; Barguzin fault
Pages: 581-592
Abstract
We studied fault scarps produced by prehistoric earthquakes in the Barguzin fault zone and estimated the ages and the magnitudes of the scarp-forming events in each scarp segment from their structure, morphology, and scarp parameters. Morphological and structural data reveal two to four surface-rupturing events with displacement up to 5-9.5 m, and two events showed 14C ages of 4.5 and 9 kyr. The area of the Barguzin Fault may have experienced six 7.5 ≥ M < 8.0 earthquakes and two M ≥ 8.0 (8.0-8.2) events for the past 10-12 kyr.
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