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Antarctic dry valleys: Microclimate zonation, variable geomorphic processes, and implications for assessing climate change on Mars
Head, James W.; Marchant, David R.
The Antarctic Dry Valleys (ADV) are generally classified as a hyper-arid, cold-polar desert. The region has long been considered an important terrestrial analog for Mars because of its generally cold and dry climate and because it contains a suite of landforms at macro-, meso-, and microscales that closely resemble those occurring on the martian s…
Martian gullies in the southern mid-latitudes of Mars: Evidence for climate-controlled formation of young fluvial features based upon local and global topography
Head, James W.; Kreslavsky, Mikhail; Dickson, James L.
A new survey of Mars Orbiter Camera (MOC) narrow-angle images of gullies in the 30°-45° S latitude band includes their distribution, morphology, local topographic setting, orientation, elevation, and slopes. These new data show that gully formation is favored over a specific range of conditions: elevation (-5000 to +3000 m), slope (>10°), and o…
Martian water vapor: Mars Express PFS/LW observations
Forget, F.; Montmessin, F.; Lellouch, E. +8 more
We present the seasonal and geographical variations of the martian water vapor monitored from the Planetary Fourier Spectrometer Long Wavelength Channel aboard the Mars Express spacecraft. Our dataset covers one martian year (end of Mars Year 26, Mars Year 27), but the seasonal coverage is far from complete. The seasonal and latitudinal behavior o…
Mechanical modeling of thrust faults in the Thaumasia region, Mars, and implications for the Noachian heat flux
Neukum, G.; Hauber, E.; Grott, M. +2 more
Insight into the state of the early martian lithosphere is gained by modeling the topography above surface breaking thrust faults in the southern Thaumasia region. Crater counts of key surface units associated with the faulting indicate a scarp emplacement in the late Noachian-early Hesperian periods between 4.0 and 3.7 Gyr. The seismogenic layer …
Valley formation on martian volcanoes in the Hesperian: Evidence for melting of summit snowpack, caldera lake formation, drainage and erosion on Ceraunius Tholus
Head, James W.; Fassett, Caleb I.
Ceraunius Tholus, a Hesperian-aged volcano in the Tharsis region, is characterized by small radial valleys on its flanks, and several larger valleys originating near its summit caldera. All of these large valleys drain from near the lowest present portion of the caldera rim and down the flanks of the volcano. The largest valley debauches into Rahe…
Assessing the limits of the Modified Gaussian Model for remote spectroscopic studies of pyroxenes on Mars
Mustard, John F.; Gendrin, Aline; Kanner, Lisa C.
We investigate the ability to refine pyroxene composition and modal abundance from laboratory and remotely acquired spectra. Laboratory data including the martian meteorites, Shergotty, Zagami, MIL03346, and ALH84001 as well as additional pyroxene-rich spectra obtained from the OMEGA (Observatoire pour la Minéralogie, l'Eau, les Glaces, et l'Activ…
Formation and disruption of aquifers in southwestern Chryse Planitia, Mars
Komatsu, Goro; Fairén, Alberto G.; Kargel, Jeffrey S. +7 more
We present geologic evidence suggesting that after the development of Mars' cryolithosphere, the formation of aquifers in southwestern Chryse Planitia and their subsequent disruption led to extensive regional resurfacing during the Late Hesperian, and perhaps even during the Amazonian. In our model, these aquifers formed preferentially along thrus…
Crater clusters on Mars: Shedding light on martian ejecta launch conditions
Richardson, Derek C.; Berman, Daniel C.; Popova, Olga P. +2 more
We have identified two classes of crater clusters on Mars. One class is "small clusters" (crater diameter D∼ tens m, spread over few hundred m), fitting our earlier calculations for the breakup of weak stone meteoroids in the martian atmosphere [Popova, O.P., Nemtchinov, I.V., Hartmann, W.K., 2003. Meteorit. Planet. Sci. 38, 905-925]. The second c…
Surface roughness and geological mapping at subhectometer scale from the High Resolution Stereo Camera onboard Mars Express
Greeley, Ronald; Mangold, Nicolas; Martin, Patrick +7 more
The quantitative measurement of surface roughness of planetary surfaces at all scales provides insights into geological processes. A characterization of roughness variations at the scale of a few tens of meters is proposed that complements the analysis of local topographic data of the martian surface at kilometer scale, as achieved from the Mars O…
A description of surface features in north Tyrrhena Terra, Mars: Evidence for extension and lava flooding
Greeley, Ronald; Neukum, Gerhard; Ori, Gian Gabriele +4 more
We studied north Tyrrhena Terra, an approximately 39,000 km 2 area, located in the transition region straddling the Amenthes and Mare Tyrrhenum Mars Chart quadrangles 14 and 22, respectively. The study area comprises ancient terrains with infilled craters, ridges and valleys. Interpretation of orbiter data of ancient terrains is inheren…