Search Publications
Large-scale spring deposits on Mars?
van Gasselt, Stephan; Neukum, Gerhard; Hauber, Ernst +5 more
We present a large-scale spring hypothesis for the formation of various enigmatic light-toned deposits (LTDs) on Mars. Layered to massive LTDs occur extensively in Valles Marineris, chaotic terrains, and several large craters, in particular, those located in Arabia Terra. Most of these deposits are not easily explained with either a single process…
Monte Carlo model of electron transport for the calculation of Mars dayglow emissions
Leblanc, F.; Gérard, J. -C.; Shematovich, V. I. +3 more
A model of the photoelectron collision-induced component of the Mars dayglow using recent cross sections and solar flux is described. The calculation of the photoelectron source of excitation is based on a stochastic solution of the Boltzmann equation using the direct simulation Monte Carlo method. The neutral atmosphere is taken from outputs of a…
Geomorphic evidence for former lobate debris aprons at low latitudes on Mars: Indicators of the Martian paleoclimate
Neukum, G.; Hauber, E.; van Gasselt, S. +1 more
Circumferential depressions enclosing mesas and plateaus in the northern Kasei Valles and in the Tartarus Colles regions of Mars are interpreted as indicators of the former extent of lobate debris aprons, thought to be mixtures of ice and clastic particles. These former lobate debris aprons existed about 1 Ga ago and were embayed by lavas or other…
Geomorphic study of fluvial landforms on the northern Valles Marineris plateau, Mars
Mangold, N.; Quantin, C.; Neukum, G. +2 more
Fluvial landforms are observed on the plateau near Echus Chasma and other locations on the Valles Marineris plateau using high resolution (10 to 50 m/pixel) Mars Express images and topography. Branching valleys have a 20- to 100-m deep V-shape profile typical of fluvial processes. Their incision occurred in a thin (<150 m) and weak, dark unit t…
Geological context of water-altered minerals in Valles Marineris, Mars
Hynek, Brian M.; Chojnacki, Matthew
Greater than 15,000 km2 of the layered deposits within Valles Marineris are associated with water-altered minerals, yet their origin and history of alteration remain a mystery. There are numerous competing hypotheses for the formation of the interior layered deposits including aeolian, lacustrine, and volcanic. Recent orbiter spectrosco…
Stratigraphy and structure of interior layered deposits in west Candor Chasma, Mars, from High Resolution Stereo Camera (HRSC) stereo imagery and derived elevations
Scholten, F.; Neukum, G.; Hauber, E. +5 more
Interior layered deposits (ILDs) within western Candor Chasma were studied by mapping lithologies, measuring layer attitudes and comparing the stratigraphy of two adjacent mounds. Layering tends to dip in the same direction as the local topographic slope, although at different angles. Regionally consistent attitudes do exist, suggesting postdeposi…
Relative age of interior layered deposits in southwest Candor Chasma based on high-resolution structural mapping
Kirk, Randolph L.; McEwen, Alfred S.; Okubo, Chris H. +1 more
High-resolution topography generated from stereo HiRISE (High-Resolution Imaging Science Experiment) imagery reveals the meter-scale structure of interior layered deposits (ILD) in southwest Candor Chasma. This study seeks to determine the age of the local ILD relative to any normal faults that can be attributed to chasma formation. The study area…
Tyrrhena Patera: Geologic history derived from Mars Express High Resolution Stereo Camera
Greeley, Ronald; Williams, David A.; Neukum, Gerhard +4 more
We used Mars Express High Resolution Stereo Camera images of the Tyrrhena Patera volcano to assign cratering model ages to material units defined in the Viking Orbiter-based geologic mapping. Cratering model ages are generally consistent with their stratigraphy. We can identify three key intervals of major activity at Tyrrhena Patera: (1) formatio…
Ferric oxides in East Candor Chasma, Valles Marineris (Mars) inferred from analysis of OMEGA/Mars Express data: Identification and geological interpretation
Sotin, Christophe; Le Mouélic, Stéphane; Gendrin, Aline +7 more
The mineralogical composition of the Martian surface is constrained by analyzing the data of the OMEGA visible and near infrared imaging spectrometer onboard Mars Express. Ferric signatures had previously been reported in Valles Marineris, Margaritifer Terra, and Terra Meridiani. Here we use three independent data reduction methods (Spectral Angle…
Topography of valley networks on Mars from Mars Express High Resolution Stereo Camera digital elevation models
Mangold, Nicolas; Neukum, Gerhard; Masson, Philippe +2 more
Martian valley networks have been identified mainly in the Noachian heavily cratered uplands. The geometry of valley networks can be studied using Mars Orbiter Laser Altimeter (MOLA) altimetry, which is sufficient to map large valleys without a detailed 3-D shape of valley networks. Imaging from the Mars Express High Resolution Stereo Camera (HRSC…