A Subsurface Origin for Warrego Vallis channels on Mars: Implications for the Early “Warm-Wet” Paradigm.
- Paper number
IAC-07-A5.I.-A3.I.B.10
- Author
Mr. Sanjoy Som, University of Washington, United States
- Coauthor
Dr. David Montgomery, University of Washington, United States
- Year
2007
- Abstract
Since its discovery by the Viking Orbiters in the 70’s, Warrego Vallis has been cited as evidence linking the early environment of Mars to being “warm and wet”. Indeed, its Noachian age (> 3.5 Ga) and a dendritic morphology like that of channel networks on Earth, have been proposed to suggest precipitation of liquid water on a drainage area. However, detailed analyses using the Thermal Emission Imaging System (THEMIS), the Mars Orbiter Camera (MOC) and the Mars Orbiter Laser Altimeter (MOLA) reveal morphological characteristics inconsistent with a mature system formed by liquid water precipitation. Specifically, the widths of individual channels do not increase downstream, and channels can be traced upstream to an origin at the base of a ridge, where they start “fully formed”, pointing to a subsurface, point source origin of the fluid that carved the channels. Therefore, despite its dendritic morphology, we argue that the additional considerations outlined above are more consistent with subsurface sources of water decoupled from the atmosphere, rather than from meteoritic water fed by precipitation from an active hydrological cycle. While we acknowledge the likelihood of the atmosphere having been somewhat denser in the past to support liquid water on the surface for some period of time, our work suggests that the morphology of the Warrego Valles channels does not necessarily bear witness to repeated long duration water flows, as has been argued previously.
- Abstract document
- Manuscript document
IAC-07-A5.I.-A3.I.B.10.pdf (🔒 authorized access only).
To get the manuscript, please contact IAF Secretariat.