thumbnail

Seasonal activity and morphological changes in martian gullies

Icarus

By:
, , , ,
DOI: 10.1016/j.icarus.2012.04.005

Links

Abstract

Recent studies of martian dune and non-dune gullies have suggested a seasonal control on present-day gully activity. The timing of current gully activity, especially activity involving the formation or modification of channels (which commonly have been taken as evidence of fluvial processes), has important implications regarding likely gully formation processes and necessary environmental conditions. In this study, we describe the results of frequent meter-scale monitoring of several active gully sites by the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter (MRO). The aim is to better assess the scope and nature of current morphological changes and to provide improved constraints on timing of gully activity on both dune and non-dune slopes. Our observations indicate that (1) gully formation on Mars is ongoing today and (2) the most significant morphological changes are strongly associated with seasonal frost and defrosting activity. Observed changes include formation of all major components of typical gully landforms, although we have not observed alcove formation in coherent bedrock. These results reduce the need to invoke recent climate change or present-day groundwater seepage to explain the many martian gullies with pristine appearance.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Seasonal activity and morphological changes in martian gullies
Series title:
Icarus
DOI:
10.1016/j.icarus.2012.04.005
Volume
220
Issue:
1
Year Published:
2012
Language:
English
Publisher:
Elsevier
Publisher location:
Amsterdam, Netherlands
Contributing office(s):
Astrogeology Science Center
Description:
20 p.
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
First page:
124
Last page:
143
Other Geospatial:
Mars