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DRY (?) MARS: AEOLIAN PROCESSES, MASS WASTING, and ROCKS 7:00 P.M

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DRY (?) MARS: AEOLIAN PROCESSES, MASS WASTING, and ROCKS 7:00 P.M Lunar and Planetary Science XXXVI (2005) sess44.pdf Tuesday, March 15, 2005 POSTER SESSION I: DRY (?) MARS: AEOLIAN PROCESSES, MASS WASTING, AND ROCKS 7:00 p.m. Fitness Center Mullins K. F. Hayward R. K. Titus T. N. Bourke M. C. Fenton L. K. Mars Digital Dune Database: A Quantitative Look at the Geographic Distribution of Dunes on Mars [#1986] Initial steps in developing a digital dune database in a global geographic context for Mars have been completed. This database currently contains information delineating the dune fields between ±65 degrees latitude. Banks M. Bridges N. T. Benzit M. Measurements of the Coefficient of Restitution of Quartz Sand on Basalt: Implications for Abrasion Rates on Earth and Mars [#2116] Using high speed video to assess grain-rock interactions, it was found that the KE lost on impact is generally proportional to incoming velocity and impact angle, but that only a fraction of this energy goes into direct abrasion of the rock surface. Neakrase L. D. V. Greeley R. Williams D. A. Reiss D. Michaels T. I. Rafkin S. C. R. Neukum G. HRSC Team Hecates Tholus, Mars: Nighttime Aeolian Activity Suggested by Thermal Images and Mesoscale Atmospheric Model Simulations [#1898] Previously unidentified wind streaks identified on nighttime IR images on Hecates Tholus volcano on Mars agree with predictions of nighttime patterns by an atmospheric model, suggesting that nighttime winds are responsible for modifying the surface in contrast to afternoon winds. Neakrase L. D. V. Greeley R. Iversen J. D. Balme M. R. Foley D. J. Eddlemon E. E. Dust Devils on Mars: Effects of Surface Roughness on Particle Threshold [#1857] The aim of this study is to determine experimentally the effects of non-erodable roughness elements on vortex particle threshold through laboratory simulations of natural surfaces pertaining to dust devils on Earth and Mars. Schneider R. D. Hamilton V. E. Variations Among Dark-toned Intracrater Deposits in Amazonis Planitia [#1543] We have performed an analysis with THEMIS data that indicates there are visible and spectral variations among 21 dark-toned intracrater deposits in Amazonis Planitia. We explore the reasons for spectral differences among the three types of deposits. Foley D. J. Whelley P. L. Greeley R. Neakrase L. D. V. Dust Devil Tracks on Mars: Observation and Analysis from Orbit and the Surface [#1162] The Mars Exploration Rover Spirit traversed a dust devil track. Analysis of dust and fine particles present inside, on the contact, and outside of the track support the hypothesis that dust devils can remove dust and fine particles from the surface. Gibbons A. Yang F. Mlsna P. Geissler P. E. Automated Procedures for Detecting Martian Dust Devils [#2005] We have begun to explore the application of numerical pattern recognition techniques to the problem of identifying Martian dust devils in orbital imagery. Scott A. G. Williams W. J. W. Mazumder M. K. Biris A. Srirama P. K. Bridging a High School Science Fair Experience with First Year Undergraduate Research: Using the E-SPART Analyzer to Determine Electrostatic Charge Properties of Compositionally Varied Rock Dust Particles as Terrestrial Analogues to Mars Materials [#2284] More is known about Mars from data collected in 2004. We present particle size and electrostatic data for particles derived from various terrestrial materials to provide analogue studies for what also appears to be present: sedimentary compositions. Lunar and Planetary Science XXXVI (2005) sess44.pdf Chojnacki M. Jakosky B. M. Hynek B. M. Surficial Properties of Landslide Units in Ophir Chasma, Mars, from Remote-sensing Data [#2323] We mapped the surface layers of the Ophir Chasma region of Valles Marineris using observations made by the MGS’s TES and the MO’s THEMIS. We found the landslide units of Ophir’s north wall to have a diverse range of characteristics. Barnouin-Jha O. S. Wada K. Matsui T. Sugita S. The Flow Dynamics of Long Run-Out Landslides on Mars from 3-D Granular Flow Models [#1588] We use 3-D granular flow models to constrain morhological and topographic attributes of long run-out landslides on Mars. Pierre N. M. Yingst R. A. Johnson J. R. Classification of Mars Pathfinder Rocks Using Multispectral Data [#1948] This study represents the first attempt at a systematic spectral classification of a significant percentage of rocks at the Mars Pathfinder landing site, and is part of a larger effort to correlate quantitative rock morphology with spectral data. Yingst R. A. Biedermann K. L. Pierre N. M. Haldemann A. F. C. Johnson J. R. Correlation of Rock Spectra with Quantitative Morphologic Indices: Evidence for a Single Rock Type at the Mars Pathfinder Landing Site [#1896] We compare multispectral data with quantitative indices of morphologic characteristics to determine the number of unique rock mineralogies — as opposed to purely external or surface materials — at the Mars Pathfinder landing site. .
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