The age and exhumation time of the Eastern Kamchatka sedimentary complexes based on apatite track dating

Abstract

The paper presents and analyzes new and previously published data on track dating of detrital apatite grains isolated from different-age structural complexes of Eastern Kamchatka. The investigations were carried out in areas with different geodynamic settings. These were the Kronotskii Peninsula which is situated in the zone of convergence of the Kamchatka margin with the relatively warm and light oceanic crust of the Pacific plate with the Obruchev Rise, the Kamchatkii Mys Peninsula which is situated in the area of collision of the Commander block of the Aleutian volcanic arc and the continental margin of Kamchatka, and the the Kumroch Ridge complexes of which belong to the Ozernovsky-Valaginskii and Vetlovskii terranes. The analysis allows distinguishing several exumation events: 29.9–34.9, 19.3–24.1, 10.2–15.4, 6.2–8.6, and 3.3–5.1 Ma. The highlighted age intervals correlate well with the main tectonic events and allow us to conclude that accretionary and collisional processes in Eastern Kamchatka continued from the Oligocene to the Late Miocene-Pliocene.

Keywords

• kamchatka
• fission track dating
• apatite
• age
• tectonics
• exhumation
• plate convergence