Geologic and geomorphic analyses reveal the effects of fluvial processes within Tyrrhena Terra, Promethei Terra and Libya Montes, Mars. High-resolution Mars Orbiter Camera (MOC), Thermal Emission Imaging System (THEMIS) visible and thermal infrared wavelength images, Viking Orbiter images, Thermal Emission Spectrometer (TES) and Mars Orbiter Laser Altimeter (MOLA) topographic data are used to qualitatively and quantitatively characterize highland fluvial systems and analyze the role of water in the evolution of these highland terrains. Highland materials--including rugged uplands, intermontane basin-filling materials, plains and impact crater ejecta deposits--are dissected by both widespread, well-integrated valley networks, such as Vichada Valles in Tyrrhena Terra, and small-scale isolated networks and single channels. The interior and exterior rims of impact craters, such as crater Millochau, are also dissected by gullies. Characterization of these features and the geologic units in which they occur is necessary to fully understand the nature of martian fluvial activity and the history of Mars' climate. High-resolution (128 pixels/degree) MOLA Digital Elevation Models (DEMs) are used with the Arc/Info GIS software (including GRID, ARCPLOT, and ArcView 3.2a) and GRIDVIEW to quantitatively characterize the surface hydrology of Tyrrhena Terra, Promethei Terra and Libya Montes. Drainage basin divides and valley networks are modeled at different scales dependent on the depth to which anomalous pixel sinks are filled. Modeled drainage divides are defined by the distribution of highland peaks and impact crater rims. Hydrologic modeling results suggest that large areas of apparently undissected terrain in Tyrrhena Terra may have been influenced by fluvial processes. Compared to mapped networks, models of large-scale valley systems in Tyrrhena Terra accurately represent the locations of valleys down to at least second order. Smaller-scale systems observed in Promethei Terra and Libya Montes are more difficult to accurately represent with the model due to a combination of a large amount of topographic interpolation within the MOLA DEM and the close spacing of short, narrow valleys Rigorous comparison of the model results to image data is helping to produce accurate maps of martian drainage basins and their associated valley networks, which provide critical constraints for valley formation mechanisms and climate history.
| Identifer | oai:union.ndltd.org:PITT/oai:PITTETD:etd-10102004-221931 |
| Date | 31 January 2005 |
| Creators | Mest, Scott Charles |
| Contributors | Dr. John Grant, Dr. David Crown, Dr. William Harbert, Dr. Mark Evans, Dr. Michael Ramsey |
| Publisher | University of Pittsburgh |
| Source Sets | University of Pittsburgh |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.library.pitt.edu/ETD/available/etd-10102004-221931/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to University of Pittsburgh or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
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