The comparative planetary geology of oceans, lakes and outflow channels on Mars

Abstract

Recently obtained high-resolution satellite imagery has enabled the detailed study of Martian geology and sedimentology. The identification of hydrological features, such as ocean, lakes, valley networks , and outflow channels, on the ancient surface of Mars is critically important to assess the history of water on the planet and to improve our understanding of the Martian climate record. Increasing evidence supports the presence of Noachian age lakes and valley networks, and Hesperian age oceans and outflow channels, although whether these features were formed by liquid water is still controversial. Clay minerals, such as phyllosilicates, have been identified in Noachian sediments within purported paleo-crater lakes, consistent with a fluvial and/or lacustrine origin. These rocks have been targeted by US and European space agencies as possible landing sites for future rover missions, with an outcrop in a hypothesized paleo-crater lake basin selected as the landing site for the next National Aeronautics and Space Administration (NASA) expedition to Mars. Increasing the research contribution of terrestrial geologists during future Martian exploration is key, because determining terrestrial analogues for features on Mars is critically important for the interpretation of Martian geological data.