Late Quaternary glacial and climate history of the Pamir Mountains derived from cosmogenic Be-10 exposure ages

摘要

Moraines southwest of Lake Yashilkul, Pamir, Tajikistan, were dated using Be-10 exposure ages of boulder surfaces. We found evidence for (1) an extensive glaciation similar to 60,000 yr ago; (2) a less extensive glacial advance, which deposited a characteristic hummocky moraine lobe with exposure ages ranging from similar to 11,000 to 47,000 yr, probably deposited at or before 47,000 yr ago; and (3) lateral moraines with exposure ages of similar to 40,000 yr, 27,000 yr and 19,000 yr, respectively. Increasing aridity in the Pamir is most likely responsible for the progressively limited extent of the glaciers during the Late Pleistocene. (c) 2005 University of Washington. All rights reserved.