Inverted channel variations identified on a distal portion of a bajada in the central Atacama Desert, Chile.

ABSTRACT: In deserts, the interplay between occasional fluvial events and persistent aeolian erosion can form composite modern and relict surfaces, especially on the distal portion of alluvial fans. There, relief inversion of alluvial deposits by differential erosion can form longitudinal ridges. We identified two distinct ridge types formed by relief inversion on converging alluvial fans in the hyperarid Chilean Atacama Desert. Although they are co-located and similar in scale, the ridge types have different ages and formation histories that apparently correspond to minor paleoclimate variations. Gravel-armored ridges are remnants of deflated alluvial deposits with a bimodal sediment distribution (gravel and sand) dated to a minor pluvial phase at the end of the Late Pleistocene (~12 kyr). In contr

SUBMITTER: Williams RME 

PROVIDER: S-EPMC8587680 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature