Subsurface Sediment Mobilization on Mars: Insights Provided by Orbital Remote Sensing Datasets

Abstract

Mud volcanism, a specific type of subsurface sediment mobilization process known to occur on Earth, has been suggested to explain the formation of morphologically diverse edifices across the surface of Mars. Previous studies have provided valuable knowledge about the morphometry, morphology, and geologic setting of putative Martian mud volcanoes. However, major knowledge gaps pertaining to the compositional characteristics of these features remain. This dissertation primarily focuses on the use of multiple orbital remote sensing datasets to investigate the mineralogical characteristics of putative Martian mud volcanoes. The validity of the mud volcanism hypothesis for pitted cones in a northern hemisphere study region of Mars is assessed, and the mineralogy of postulated Martian mud volcanoes is examined on a global scale through the use of some of the highest resolution orbital datasets currently available to study surface features on Mars. This dissertation also provides supplemental knowledge to these compositional analyses through the incorporation of an expanded morphometric dataset, a spatial analysis methodology, and the first application of an analytical modeling technique to the study of proposed mud volcanoes on Mars. Microbial activity has been documented at both onshore and offshore mud volcanism system sites on Earth. Therefore, the possibility that this geologic process once operated on the surface of Mars is intriguing given the astrobiological potential of the associated locations, as well as the ability to study sediments that would otherwise be inaccessible and possibly represent life in the deep biosphere of a second terrestrial planet in the Solar System. The study of this geologic process on Mars is also worthwhile due to implications for Martian climate, comparative planetology, and future landed mission exploration of the Martian surface.