АКТИВНАЯ РАЗЛОМНАЯ ТЕКТОНИКА СРЕДИННОГО ХРЕБТА, П-ОВ КАМЧАТКА

Abstract

The paper presents the results of remote sensing interpretation of active faults of the Sredinny Range of Kamchatka. The use of remote sensing data allowed us to identify fault scarps and magma-conducting fractures, expressed in the topography by chains of eruption centers. Most of the detected faults are located on volcanic plateaus, what indicates the relation of faulting with thinning of the brittle crust under the volcanic belt, similar to the faults of the Eastern Volcanic Belt. The geometrical characteristics of the most preserved scarps provide an estimate of the magnitude of paleoearthquakes Mw = 5.8±0.2, which significantly exceeds the historical seismicity. The identified faults are located above the northern edge of the subducted portion of the Pacific plate and form a zone oblique to the axis of the Kuril-Kamchatka island-arc system. The strike and normal sense of the faults are consistent with the transverse extension in Kamchatka. These new data provide the northern and western boundaries of the above-subduction extensional setting in Kamchatka.