2017/04/27 by Dylan J. Ward, Rachel M. Thornton, Jason M. Cesta · 2 citations
Earth and Planetary Sciences · Social Sciences · #Geology and Paleoclimatology Research #Evolution and Paleontology Studies #Pleistocene-Era Hominins and Archaeology #Moraine #Deglaciation #Glacial period #Geology #Glacier #Physical geography #Arid #Glacial landform #Last Glacial Maximum #Geomorphology #Paleontology #Geography
paper · pdf · doi:10.18172/cig.3209
openalex publication_date 2017/04/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/26
Here we review published cosmogenic records of glaciation and deglaciation from the western cordillera of the arid subtropical Andes of northern Chile and southwest Bolivia. Specifically, we examine seven published studies describing exposure ages from moraines and glaciated bedrock spanning the glaciological Arid Diagonal, the region of the dry Andes where there is no clear evidence for glaciation over at least the last global glaciation. We also present new cosmogenic 36Cl exposure ages from two previously undated sets of moraines in the deglaciated region near 22ºS. Taken together, these records indicate that the most extensive regional glaciation occurred ca. 35-45 ka, followed by slow, punctuated retreat through the global last glacial maximum, and rapid retreat after ~15-17 ka. In the vicinity of the large Altiplanic lakes that existed during the late glacial stage, the 15-17 ka moraines overrode the earlier moraines, whereas elsewhere regionally, on both sides of the Arid Diagonal, late glacial wet periods are represented only by less-prominent moraines in more retracted positions.