Inverted fluvial features in the Aeolis-Zephyria Plana, western Medusae Fossae Formation, Mars: Evidence for post-formation modification
The Aeolis and Zephyria Plana contain the western‐most portion of the Medusae Fossae Formation (MFF), an enigmatic and extensive light‐toned deposit located in the Martian equatorial region and dated from the Hesperian to Amazonian epochs. This area hosts a large population of sinuous ridges (SRs),...
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Published in | Journal of Geophysical Research: Planets Vol. 117; no. E3 |
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Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
Washington, DC
Blackwell Publishing Ltd
01.03.2012
American Geophysical Union |
Subjects | |
Online Access | Get full text |
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Summary: | The Aeolis and Zephyria Plana contain the western‐most portion of the Medusae Fossae Formation (MFF), an enigmatic and extensive light‐toned deposit located in the Martian equatorial region and dated from the Hesperian to Amazonian epochs. This area hosts a large population of sinuous ridges (SRs), interpreted as inverted fluvial features, formed by precipitation, indurated by chemical cementation, buried by subsequent deposition, and finally exhumed. This interpretation of SRs as uniformly fluvial represents a modification to an earlier hypothesis for one particular SR of possible glaciofluvial (i.e. esker) formation. These SRs provide a tool to investigate the degree and character of post‐fluvial modification processes in this region. We combined digital terrain models made from Context Camera (CTX) and High Resolution Imaging Science Experiment (HiRISE) stereo image pairs with individual data points from the Mars Orbiter Laser Altimeter (MOLA) to estimate relief, cross‐sectional profiles, longitudinal profiles and slope directions of selected SRs. Longitudinal profiles of several SRs display undulations with amplitudes of up to order 100 m. While some of the lower amplitude undulations may be due to differential erosion, undulations having amplitudes in excess of SR relief require alternative explanations. Our combined morphologic and topographic analysis suggests that multiple post‐flow processes, including compaction of the deposits and tectonic displacements, have modified the original SR profiles. Specification of the type(s) and magnitudes of these modification processes will contribute to understanding both the potential of post‐flow modification of fluvial profiles elsewhere on Mars as well as the nature and properties of the MFF.
Key Points
Topographic profiles of inverted fluvial features show post‐flow deformation
Compaction or tectonics may have occurred in the Medusae Fossae Formation |
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Bibliography: | istex:86110FBF470C5A85C09EB9FD93AC6344F471200B ark:/67375/WNG-QCQF4X34-H Tab-delimited Table 1.Tab-delimited Table 2. ArticleID:2011JE004008 ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 |
ISSN: | 0148-0227 2169-9097 2156-2202 2169-9100 |
DOI: | 10.1029/2011JE004008 |