Towards an understanding of the Geological History of Valles Marineris, Mars

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Mars exhibits the most Earth-like conditions of all planets within our solar system and is affected by many of the same geological processes found on Earth. Volcanism, wind erosion, water-driven processes and glaciers have all played a role in shaping the surface of Mars. This similarity has inspired mankind's imagination for a long time and understanding the geological history of Mars has been an important goal for researchers. Because of the lack of plate tectonics, the Martian surface preserves an earlier stage of planetary evolution than we can easily access on Earth. The primary goal of the current NASA Curiosity rover mission within the ~3.6 billion year old Gale crater is to investigate whether Mars had an environment able to support life by investigating layered deposits in that crater. Valles Marineris is a similarly aged, 4000 km long, 400 km wide and up to 10 km deep system of linked chasms that has been compared to large rift valleys on Earth. The chasms of Valles Marineris are partially filled with layered deposits up to 8 km thick. Their association with sulfate mineralogy makes them similar to some deposits in Gale Crater. In this research program we continue our investigation into how this chasm system formed, and how and to what extent each chasm was filled with layered deposits. Understanding the mechanism of the chasm formation and filling addresses important environmental factors such as the availability of water or ice. Our technique is to use of digital imagery with a resolution of up 25 cm/pixel and of digital terrain models with resolutions as low as 1 m/pixel. This will allow us to view and measure small-scale features in 3D. For investigation of layered deposits this information will be supplemented by mineralogical observations from existing orbiting hyperspectral sensors. We will also be able to use the results of remotely sensed chemical analyses and eventually compare our observations with those obtained by Curiosity when it reaches layered deposits with similar sulfate composition within Gale. This research will result in a better understanding of the early geological history and of the environmental conditions of Mars. This in turn enhances our understanding of the early evolution of terrestrial planets in general. It also provides important information for any plans of future human visitation of the planet and for the eventual colonization of Mars.