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Mars Geology Lunar and Planetary Science XXXIII (2002) sess27.pdf Tuesday, March 12, 2002 POSTER SESSION I 7:00–9:30 p.m. Gymnasium Mars Geology Jernsletten J. A. Latitude-dependent Topographic Variations in the Near-Equatorial Canyons of Mars (Valles Marineris Region) [#1861] This paper looks at the topography of the near-equatorial canyons of Mars. We look at variations in average slope with latitude. Differences between south- and north-facing walls and surface roughness are considered, based on MOLA and Viking data. Jernsletten J. A. The Central Mesas of Hebes, Ganges, and East Candor Chasmae [#2019] This paper compares the central mesas of Hebes, Ganges, and East Candor Chasmae. Faulting, erosion, and mass wasting are proposed as candidate post-formation evolution processes, based on the surface texture and profiles of DTMs of these canyons. Noreen E. Hare T. M. Volumetric Calculations of Valles Marineris Using MOLA Data and GIS [#1919] Prior to MGS, topographic estimations of the Valles Marineris were accomplished using photogrammetric techniques. MGS MOLA datasets coupled with GIS provide the means to re-quantify the topography of VM to a higher degree of accuracy. Maier C. M. Mapping Acidalia Mensa: Redefining Northern Plains Units and Possible Deformation History [#1360] Large-scale mapping leads to new definitions for local geologic units in the northern plains assemblage. Evidence exists for both marine and debris flow deposits. New models suggest that a mesa mapped as an ancient highland may be no older than Amazonian in age. Kostama V-P. Aittola M. Öhman T. Raitala J. Geological Units of the Hellas Basin Region, Mars [#1486] The uniform geological analysis of the greater Hellas region provides an insight into several phases of Martian geological development and offers a research platform with constant variables for future studies. Mest S. C. Crown D. A. Geology of MTM Quadrangles -20272 and -25272, Terra Tyrrhena Region of Mars [#1730] Geologic mapping of MTM Quadrangles -20272 and -25272 (1:500K scale) has allowed detailed characterization of the cratered highlands, including impact crater morphologies, dissection by fluvial valleys, and formation of intercrater plains. Hauber E. van Gasselt S. Jaumann R. Morphology and Topography of Fretted Terrain at the Dichotomy Boundary in Tempe Terra, Mars: General Characteristics [#1658] The morphology and topography of fretted terrain in Tempe Terra is similar to that elsewhere on Mars. Here we give an overview and a companion abstract (Van Gasselt et al., this volume) reports detailed volume measurements of waste morphology. Yoshikawa K. Origin of the Polygons and Underground Structures in Western Utopia Planitia on Mars [#1159] The area of lower albedo (Hvm) has a higher density of polygonal patterns. These patterns potentially suggest that 1) the polygonal pattern is caused primarily by ground heaving and collapsing, 2) lower albedo materials had higher tensile strength. Lunar and Planetary Science XXXIII (2002) sess27.pdf Kuzmin R. O. Ershow E. D. Komarow I. A. Kozlov A. H. Isaev V. S. The Comparative Morphometric Analysis of Polygonal Terrains on Mars and the Earth High Latitude Areas [#2030] The results of comparative morphometric analysis of polygonal terrains on Mars and the Earth are presented in the abstract. Mangold N. Forget F. Costard F. Peulvast J-P. High Latitude Patterned Grounds on Mars: Evidence for Recent Melting of Near-Surface Ground Ice [#1219] High resolution MOC images shows patterned ground formed by ground thawing similar to of periglacial regions on Earth. Their distribution in recent terrains at high latitudes is evidence for freeze-thaw cycles that may have been triggered by obliquity changes. Komatsu G. Di Cencio A. The Origin of Light-Color Units on the Floor of Valles Marineris, Mars [#1184] Light-color materials on the floor of Ius Chasma, a part of the Valles Marineris canyon system on Mars, appear to be exposed old layered deposits or newly formed sediments by hydrological processes. Higbie M. A. Herrick R. R. Treiman A. H. Integrated Analysis of Ganges Mensa, Mars [#1770] Using Viking, MOLA, and MOC data, we analyzed the stratigraphy of Ganges Mensa, an interior layered deposit in Ganges Chasma in eastern Valles Marineris. Geomorphic units matching topographic slope breaks were identified on the SW side of the Mensa. Frey H. V. Roark J. H. Hohner G. J. Wernecke A. Sakimoto S. E. H. Buried Impact Basins as Constraints on the Thickness of Ridged Plains and Northern Lowland Plains on Mars [#1894] The northern lowland plains average 1-2 km but locally vary from less than 0.5 to likely over 5 km in thickness. In Lunae Planum the total thickness of materials overlying likely present but not detectable 100 to 200 km wide craters is 2-3 km. Gittings H. E. Gregg T. K. P. Erosion of Extensive Tyrrhena Patera Deposits, Mars: Mechanisms and Volumes [#1773] Constraints on the nature of the erosion surrounding Tyrrhena Patera will reveal important information about the volatile and climatic history of the region by providing estimates of the eroded volumes and erosion styles. King J. D. Albin E. F. Weathering of the Continuous Ejecta Blanket Associated with the Cassini Impact Basin, Mars [#1765] This investigation is concerned with the degree or extent of removal of the Cassini impact basin’s continuous ejecta blanket through the study of weathering features using MOC and MOLA data. Johnson J. R. Lemmon M. T. Grundy W. M. Herkenhoff K. E. Dust Mineralogy and Deposition Rates on Mars from Observations of Mars Pathfinder Calibration Targets [#1392] Spectral changes in the Mars Pathfinder calibration targets during the mission indicate the deposition of atmospheric dust with spectral features suggestive of hematite and palagonite. Sky brightness and two-layer Hapke models will help constrain dust mineralogy and deposition rates. Vincendon C. Mangold N. Masson P. Ansan V. Estimation of Dust Thickness in Arabia Terra Region [#1208] This study proposes to measure and map the thickness of dust deposits in low thermal inertia regions like Arabia Terra using the distribution of small impact craters at the MOC images scale. Lunar and Planetary Science XXXIII (2002) sess27.pdf Geissler P. E. McEwen A. S. Leovy C. Biener K. K. Identifying Surface Changes on Mars from Viking and MGS [#1982] We have begun a program of combined Viking and MOC Wide Angle Camera image analysis to identify surface changes on Mars due to aeolian, mass-wasting, aqueous or volcanic processes both from Viking to MGS and from one MGS orbit to another. .
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