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. 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, a 4000 km long, 400 km wide and up to 10 km deep system of linked chasms, which has been compared to large rift valleys on Earth. The chasms are partially filled with layered deposits up to 8 km thick that are similar to those in Gale Crater. In this project we investigate how this chasm system formed, how each chasm was filled with layered deposits and by what mechanism they were subsequently eroded. Understanding the nature of the mechanism for filling and erosion addresses important environmental factors such as the availability of water or ice. Our technique is to combine digital imagery with digital terrain models with resolutions as low as 1 m/pixel. This allows us to measure small 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 the chemical analyses and grain scale observations obtained by Curiosity on layered deposits within Gale and apply them to the larger scale observations we are able to make in Valles Marineris. 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.