Cosmogenic exposure dating of snow-avalanche ridges Eastern Black Sea Mountains, NE Turkey

Abstract

Abstract The Kavron and Vercenik Valleys are located in the Eastern Black Sea Mountain range in northeastern Turkey. This study identified several snow-avalanche ridges in these glacial valleys. Those in the Kavron Valley were mapped in detail and the largest and geomorphologically oldest ridge of each valley was sampled for cosmogenic exposure dating with 10 Be. Three granitic boulders from Kavron Valley and two granitic boulders from Vercenik Valley were processed. The avalanche ridges had been mapped as terminal moraines of Pleistocene Glaciations by previous researchers. The 10 Be exposure dates obtained from each boulder are different, ranging from 7.4 to 2.3 kyr BP, and indicate that each represents an individual snow-avalanche event. These ages show that the events occurred during the Holocene and the 10 Be results confirm that the snow-avalanche ridge build–up started in the Late Glacial after the retreat of paleoglaciers in the Vercenik and Kavron Valleys.