1. The geology of ancient fluvial and lacustrine systems in Arabia Terra and Melas Chasma, Mars
- Author
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Davis, J. M.
- Subjects
550 - Abstract
Fluvial and lacustrine processes were abundant on early Mars. However, key questions remain about the extent of these processes and the climate in which they formed. This thesis examines two regions of Mars, Arabia Terra and Melas Chasma, using high-resolution, remote sensing datasets, with a focus on (1) the influence of fluvial and lacustrine processes on the landscape and (2) the implications for the early martian climate and environment. I first investigate Arabia Terra, a Noachian region of the southern highlands, and have produced a regional map of fluvial landforms. Fluvial channels and paleolakes preserved as inverted relief are pervasive throughout Arabia Terra and may represent the depositional component of a regional, south to north fluvial transport system. In addition, I have produced a geological map of one of these inverted systems, which reveals a complex stratigraphy and demonstrates that fluvio-lacustrine processes are concentrated on the oldest terrains. These fluvial systems are strongly consistent with widespread precipitation and runoff across early Mars. The second region of investigation is the Hesperian south-western Melas Chasma basin, part of the Valles Marineris canyon system. Here I have produced a map of fluvial landforms, which indicates that fluvial processes were episodic and extended over a protracted period of time. I also examine the stratigraphic sequence within the central palaeolake in the basin, where evidence for episodic aqueous processes is also identifed. The south-western Melas Chasma basin provides strong evidence that fluvio-lacustrine processes on Mars continued for much of the early and middle history of Mars.
- Published
- 2017