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Early oceans on Mars
Project Investigators:
Other Project Members
Amy Daradich (No Role Selected)Michael Manga (No Role Selected)Jerry Mitorvica (No Role Selected)Taylor Perron (No Role Selected)edwin kite (Doctoral Student)Summary
We investigate the possible origin and fate of oceans early in Martian history.
Astrobiology Roadmap Objectives:
- Objective 1.1: Models of formation and evolution of habitable planets
- Objective 2.1: Mars exploration
Project Progress
In the previous year we suggested that the signature of large past oceans on Mars is preserved as deformed shorelines following an episode of true polar wander (Perron et al., 2007). We investigated the relic signature of this possible polar wander in the present day Martian gravity field. We are unable to rule out the possibility of significant polar wander (Daradich et al., 2008).
Water-lain sediments associated with the proposed northern ocean on Mars
have not been found. In the west of the Hellas basin, however, wind
erosion has exposed deep-lying, deformed layered terrain. Earlier work
based largely on Viking data identified Hellas as a candidate ocean, and
these deformed layers may be its sedimentary record. But spectroscopic
confirmation is lacking, in part because Hellas is coated by bright,
anhydrous dust.Thick evaporite deposits on Early Mars would have been unstable to thermal
convection. The deformed layered terrain shows a kilometer-scale cellular
pattern, consistent with both thermal convection and compositional
convection. We have assembled a GIS of the Western Hellas region to map
and understand stratigraphic relationships. We are working to quantify the observed deformation, and relate these measurements to 2D numerical simulations of diapirism and convection within sedimentary deposits. Our short-term objective is to determine the thickness, and constrain the effective viscosity, of the deformed layered terrain.Possible shear zone formed by thermochemical convection in ocean-deposited evaporites.Publications
Daradich, A. (2008). Equilibrium rotational stability and figure of Mars. Icarus, 194:463-475.
Kite, E.S. (submitted). True polar wander driven by late-stage volcanism and the distribution of paleopolar deposits on Mars. Geophysical Research.
- Landforms made by groundwater discharge on Mars and Earth
- Characterization of Aqueous Processes on Mars Through Spectral Remote Sensing
- Climate, Habitability, and the Atmosphere on early Mars
- Early oceans on Mars
- Earthbound microbial and geological robotic based observations for Mars
- Evolution of the interior and its consequences for water on Mars
- Iron and sulfur-based biospheres and their biosignatures
- Isotopic fingerprints of past life and surface conditions on Mars