Neotectonics and recent uplift at Kamchatka and Aleutian arc junction, Kamchatka Cape area, NE Russia

Abstract

The tectonic position of the Kamchatka Cape Peninsula at the junction of the active Kuril–Kamchatka and Aleutian arcs exposes the coastline of the peninsula to strong neotectonic activities. Fracture zones have variable influence on uplift of the Kamchatka Cape Peninsula. Relevant morphologic indicators of neotectonic activity are multilevel, highly uplifted marine terraces and terraces displaced along active faults. Recent uplift rates of coastal sediments are determined by remote sensing via ASTER and SRTM DEM combined with optically stimulated luminescence dating (OSL). On the Kamchatka Cape Peninsula, terraces from the same generation are mapped at different elevations by remote sensing methods. After defining different areas of uplifted terraces, four neotectonic blocks are identified. According to apatite fission track data, the mean differential exhumation rates range from 0.2 to 1.2 mm year−1 across the blocks since Late Miocene. The OSL data presented point to significant higher uplift rates of up to 3 ± 0.5 and 4.3 ± 1 mm year−1, which indicates an acceleration of the vertical movement along the coast of Kamchatka Cape Peninsula in Upper Pleistocene and Holocene times.