Dune morphology, sand transport pathways and possible source areas in east Thaumasia Region (Mars)

An aeolian system located in Aonia Terra (eastern Thaumasia region) consists of six dark dune fields. The dune pattern suggests an organized extended sand transport system, which is characterized by the presence of long sand corridors. The latter connects the different ergs with potential sources. The sand stored in the ergs is provided by layered materials exposed in pits and crater walls and by the ergs themselves. Most of the sand converges from the marginal dune fields into the central erg C. The latter develops in an area of convergence of at least three different winds: from the southwest, the northeast and the northwest. The northwesterly flows seem to postdate the other winds as suggested by the development of a complex dune pattern in the western portion of the erg C, representing a successive episode of aeolian construction. Collectively such complex dune patterns show how dune fields could record major changes in the wind regimes of Mars.