Search Publications
Delineation of alluvial fans from Digital Elevation Models with a GIS algorithm for the geomorphological mapping of the Earth and Mars
Norini, Gianluca; Zuluaga, Maria Clara; Ortiz, Iris Jill +2 more
Alluvial fans are prominent depositional geomorphic features present in nearly all global climates on Earth, and also found on Mars. In this study, we present a Geographic Information System (GIS) algorithm designed for the semi-automated detection of alluvial fans that are connected to their contributing upstream drainage network, from the analys…
Mechanical conditions and modes of paraglacial deep-seated gravitational spreading in Valles Marineris, Mars
Mège, Daniel; Makowska, Magdalena; Gueydan, Frédéric +1 more
Deep-seated gravitational spreading (DSGS) affects the slopes of formerly glaciated mountain ridges. On Mars, DSGS has played a key role in shaping the landforms of the giant Valles Marineris troughs. Though less spectacular, DSGS is common in terrestrial orogens, where understanding its mechanics is critical in the light of the ongoing climate ch…
Analysis of crater valleys, Noachis Terra, Mars: Evidence of fluvial and glacial processes
Hobbs, S. W.; Paull, D. J.; Clarke, J. D. A.
The precise mechanism for the formation and evolution of crater valley networks in the Martian southern highlands remains under debate, with precipitation, groundwater flow, and melting induced by impact being suggested. We studied valley networks within four craters of the Noachis Terra highlands that were representative of similar features in No…
Aeolian processes as drivers of landform evolution at the South Pole of Mars
Spiga, Aymeric; Holt, John W.; Smith, Isaac B.
We combine observations of surface morphology, topography, subsurface stratigraphy, and near surface clouds with mesoscale simulations of south polar winds and temperature to investigate processes governing the evolution of spiral troughs on the South Pole of Mars. In general we find that the south polar troughs are cyclic steps that all formed du…
Object-based Dune Analysis: Automated dune mapping and pattern characterization for Ganges Chasma and Gale crater, Mars
Fenton, Lori K.; Michaels, Timothy I.; Vaz, David A. +2 more
A method that enables the automated mapping and characterization of dune fields on Mars is described. Using CTX image mosaics, the introduced Object-based Dune Analysis (OBDA) technique produces an objective and reproducible mapping of dune morphologies over extensive areas. The data set thus obtained integrates a large variety of data, allowing a…
Channel slope reversal near the Martian dichotomy boundary: Testing tectonic hypotheses
Nimmo, Francis; Burr, Devon M.; Jacobsen, Robert E. +1 more
Faults along the Martian dichotomy boundary are evidence of tectonic activity, which by analogy with terrestrial tectonism may cause changes in or even reversal of fluvial longitudinal profiles. In the eastern hemisphere between 30° E and 150° E, this tectonic activity has been hypothesized to result from lower crustal flow or from lithospheric fl…
An introduction to the data and tools of planetary geomorphology
Beyer, Ross A.
This manuscript presents a review of data used by planetary geomorphologists and the software tools needed to prepare, process, and analyze those data, along with an example of doing so. Visible image capture and the photometric and geometric processing of those images are reviewed, as are laser altimetry data, and terrain data derived from images…
Hydrographs of a Martian flood from the breach of Galilaei Crater
Coleman, Neil M.
Spectacular floods were spawned on Mars when large craters filled to overtopping and catastrophically breached. The wealth of data now available permits quantitative analysis of these ancient floods. Galilaei Crater is examined here, along with the likely sources of its water and the processes that formed Tana Vallis, its 1-km-deep outflow channel…
One million cubic kilometers of fossil ice in Valles Marineris: Relicts of a 3.5 Gy old glacial landsystem along the Martian equator
Le Mouélic, Stéphane; Le Deit, Laetitia; Mège, Daniel +6 more
Self-consistent landform assemblages suggest that Valles Marineris, the giant valley system that stretches along the Martian equator, was entirely glaciated during Late Noachian to Early Hesperian times and still contains huge volumes of fossil ice. Some of these glacial landform assemblages are illustrated here, with representative examples selec…
Friction and dynamics of rock avalanches travelling on glaciers
De Blasio, Fabio Vittorio
Rock avalanches travelling on glaciers often exhibit effective friction coefficient lower than those on a rocky terrain. After briefly considering some data of rock avalanches on glaciers, the physics of sliding of solid objects on icy surfaces is reviewed, and a model is put forward for the mechanics of rock avalanche sliding on ice accounting fo…