Dark aeolian megaripples from the Puna of Argentina: sedimentology and implications for dark dunes on Mars

DE SILVA, S.L.; BURR, D.M.; ORTIZ, A.; SPAGNUOLO, M.; ZIMBELMAN, J.R.; BRIDGES, N.T.

Woodland, Texas

Congreso; 43rd Lunar and Planetary Science Conference; 2012

Dark dunes on Mars have beenhypothesized as volcaniclastic sediments [1], includingthose of the western Medusae Fossae Formation (MFF)[e.g., 2,3,]. Thus, comparison between the western MFFand terrestrial volcaniclastic bedform-formingsediments allows us to test this volcaniclastichypothesis for the source of dark dune sand on Mars.Herein, we describe the context and sedimentology ofdark megaripples in the Puna of Catamarca Province inArgentina as analogs for dark dunes on Mars. We positthat they are the final result of the erosional history ofthe local bedrock. Analogous relationships betweenbedforms, topography, and bedrock [4, this conf.] andequivalent weights of materials on the Puna and Marsprovide the basis for comparison.