Dark material in the polar layered deposits and dunes on Mars

Abstract

Abstract. Viking infrared thermal mapping and bistatic radar data suggest that the bulk density of the north polar erg material is much lower than that of the average Martian surface or of dark dunes at lower latitudes. We have derived a thermal inertia of 245-280 J m -2 s -1/2 K -1

Extraterrestrial dunes: An introduction to the special issue on planetary dune systems

“…It has been proposed that some Martian dunes could be composed of sand-sized aggregates of dust (Greeley, 1979;Saunders et al, 1985;Saunders and Blewett, 1987;Herkenhoff and Vasavada, 1999). Indeed, the Mars Exploration Rovers imaged the very smooth imprint of the APXS contact plate onto sand-like surface deposits suggesting compaction of sand-sized aggregates at some locations .…”

“…The thermal inertia data for Martian dunes suggest that they are composed of unweathered basaltic grains (Paige et al, 1994;Herkenhoff and Vasavada, 1999). Bandfield (2002) noted that the spectra of the dunes in the north polar region indicate a mixture of clasts with a bulk composition similar to andesite.…”

“…The majority of sand dunes on Mars are composed of unweathered basaltic (Paige et al, 1994;Herkenhoff and Vasavada, 1999) or andesitic (Bandfield, 2002) fragments. At two locations, sand dunes contain a significant proportion of hydrated minerals.…”

Aeolian bedforms, yardangs, and indurated surfaces in the Tharsis Montes as seen by the HiRISE Camera: Evidence for dust aggregates

“…Parna sheets have been hypothesized to occur on Mars (Greeley and Williams, 1994), but have not been identified. Aggregates have also been proposed to compose the low thermal inertia dunes and materials in the north polar erg (Herkenhoff and Vasavada, 1999).…”

Heat of Mars Is Love of Life?! Two Ways to Look at Mars

“…However, based on Viking Infrared Thermal Mapper data, Herkenhoff and Vasavada (1999) proposed that north polar dunes consists of grains smaller than sand (Paige et al 1994). The hypothesis that north polar dunes are composed of particles finer than sand, has been tested by a direct method that requires no intricate thermal modeling.…”