TY - JOUR
T1 - The geomorphology and morphometry of the banded terrain in Hellas basin, Mars
AU - Diot, X.
AU - El-Maarry, M. R.
AU - Schlunegger, F.
AU - Norton, K. P.
AU - Thomas, N.
AU - Grindrod, P. M.
N1 - Funding Information:
XD would like to thank the Center for Space and Habitability of the University of Bern for funding and supporting this study. MR EM, NT, and FS are supported by funds from the Swiss National Science Foundation (SNSF). PMG is funded by the UK Space Agency (Aurora Fellowship grant ST/J005215/1 ). The stereo DTM processing was carried out at the UK NASA RPIF at University College London. The authors would like to thank Nicolas Mangold and an anonymous reviewer for their constructive reviews, which improved the manuscript overall.
PY - 2014/10/15
Y1 - 2014/10/15
N2 - Hellas basin is a large impact basin situated in the southern highlands of Mars. The north-western part of the basin has the lowest elevation (-7.5 km) on the planet and contains a possibly unique terrain type, which we informally call "banded terrain". The banded terrain is made up of smooth-looking banded deposits that display signs of viscous behavior and a paucity of superimposed impact craters. In this study, we use newly acquired high spatial resolution images from the High Resolution Imaging Science Experiment (HiRISE) in addition to existing datasets to characterize the geomorphology, the morphometry and the architecture of the banded terrain. The banded terrain is generally confined to the NW edge of the Alpheus Colles plateau. The individual bands are ∼3-15 km-long, ∼0.3 km-wide and are separated by narrow inter-band depressions, which are ∼65 m-wide and ∼10 m-deep. The bands display several morphologies that vary from linear to concentric forms. Morphometric analysis reveals that the slopes along a given linear or lobate band ranges from 0.5°to 15°(average ∼6°), whereas the concentric bands are located on flatter terrain (average slope ∼2-3°). Crater-size frequency analysis yields an Amazonian-Hesperian boundary crater retention age for the terrain (∼3 Gyr), which together, with the presence of very few degraded craters, either implies a recent emplacement, resurfacing, or intense erosion. The apparent sensitivity to local topography and preference for concentrating in localized depressions is compatible with deformation as a viscous fluid. In addition, the bands display clear signs of degradation and slumping at their margins along with a suite of other features that include fractured mounds, polygonal cracks at variable size-scales, and knobby/hummocky textures. Together, these features suggest an ice-rich composition for at least the upper layers of the terrain, which is currently being heavily modified through loss of ice and intense weathering, possibly by wind.
AB - Hellas basin is a large impact basin situated in the southern highlands of Mars. The north-western part of the basin has the lowest elevation (-7.5 km) on the planet and contains a possibly unique terrain type, which we informally call "banded terrain". The banded terrain is made up of smooth-looking banded deposits that display signs of viscous behavior and a paucity of superimposed impact craters. In this study, we use newly acquired high spatial resolution images from the High Resolution Imaging Science Experiment (HiRISE) in addition to existing datasets to characterize the geomorphology, the morphometry and the architecture of the banded terrain. The banded terrain is generally confined to the NW edge of the Alpheus Colles plateau. The individual bands are ∼3-15 km-long, ∼0.3 km-wide and are separated by narrow inter-band depressions, which are ∼65 m-wide and ∼10 m-deep. The bands display several morphologies that vary from linear to concentric forms. Morphometric analysis reveals that the slopes along a given linear or lobate band ranges from 0.5°to 15°(average ∼6°), whereas the concentric bands are located on flatter terrain (average slope ∼2-3°). Crater-size frequency analysis yields an Amazonian-Hesperian boundary crater retention age for the terrain (∼3 Gyr), which together, with the presence of very few degraded craters, either implies a recent emplacement, resurfacing, or intense erosion. The apparent sensitivity to local topography and preference for concentrating in localized depressions is compatible with deformation as a viscous fluid. In addition, the bands display clear signs of degradation and slumping at their margins along with a suite of other features that include fractured mounds, polygonal cracks at variable size-scales, and knobby/hummocky textures. Together, these features suggest an ice-rich composition for at least the upper layers of the terrain, which is currently being heavily modified through loss of ice and intense weathering, possibly by wind.
KW - Flows
KW - Geomorphological processes
KW - Impact crater
KW - Mars
KW - Surface geology
UR - https://www.scopus.com/pages/publications/84906948969
U2 - 10.1016/j.pss.2014.06.013
DO - 10.1016/j.pss.2014.06.013
M3 - Article
AN - SCOPUS:84906948969
SN - 0032-0633
VL - 101
SP - 118
EP - 134
JO - Planetary and Space Science
JF - Planetary and Space Science
ER -