Monday, July 9, 2007 POSTER SESSION: MARS GEOLOGY

11:30 a.m. Dabney Garden Ansan V. Mangold N. Masson Ph. Neukum N. HRSC Co-Investigator Team Improvement of Valley Network 3D Geometry from HRSC DEMs Compared to MOLA Data [#3152] Here we compare the organization of valley networks in three regions (Huygens impact crater, Aeolis region and West Echus plateau) using MOLA and HRSC DEMs, and HRSC nadir images in order to quantify the difference of geometry between these datasets. Antoine R. Baratoux D. Rabinowicz M. Bachèlery P. Staudacher T. Saracco G. Fontaine F. Convective Gas Flow in Terrestrial and Martian Volcanic Soils: Implications for the Interpretation of THEMIS-IR Data [#3097] We report on the detection of convective air flow in the soil of a terrestrial volcano. Similar processes may operate on Mars as suggested by observations (THEMIS) at Cerberus fractures, motivating the search for subsurface heat source on Mars. Baptista A. R. Mangold N. Ansan V. Costard F. Masson P. Lognonné P. Neukum G. HRSC Team Coalesced Small Shield Volcanoes on Syria Planum, Mars, Detected by Mars Express — HRSC Images [#3128] We identified a swarm of tens of shallow volcanic edifices. Their characteristics correspond to those of small shield volcanoes and show that Syria Planum experienced a very specific style of volcanism which we have dated to the Hesperian period. Baratoux D. Mangold N. Arnalds O. Grégoire M. Platvoet B. Badinzeff J.-M. Pinet P. Formation, Transport and Mineralogical Evolution of Basaltic Sands on Earth and Mars [#3048] This paper focuses on the history of volcanic sands on Mars. When did they form ? Which are the sand source? Where are the sand pathways? A case study in Iceland is presented to illustrate the possible processes operating on Mars. Barnouin-Jha O. S. Buczkowski D. L. Investigating Bright-Haloed Craters in Chryse Planitia, Mars [#3378] We combine many of the new types of data that exist for Mars to constrain the origin of bright haloed craters observed in Chryse Planitia. These analyses may provide insights to how target properties, including the presence of subsurface volatiles, might influence cratering on Mars. Bishop J. L. Noe Dobrea E. Murchie S. L. Weitz C. M. Calvin W. M. Roach L. A. Pelkey S. M. Brown A. J. Mustard J. F. Bibring J.-P. MRO CRISM Team Sulfates and Mafic Minerals in Juventae Chasma as Seen by CRISM in Coordination with OMEGA, HiRISE and Context Images [#3350] Coordinated CRISM, HiRISE and CTX images of the northern mound in the Juventae Chasma interior show evidence of sulfate minerals in many regions of the mound, plus olivine and pyroxene in some lower lying terrains just north of the mound. Bowen B. B. Benison K. C. Oboh-Ikuenobe F. Mormile M. Hematite Concretions from Modern Acid Saline Lake Sediments as Geochemical and Astrobiological Tombs [#3175] Strata on Mars that reveal the importance of acid saline waters in the planet’s past are compared to modern terrestrial acid saline lake sediments that include hematite concretion-bearing evaporites with good microbial preservation potential. Boyce J. M. Major Latitude-dependent Degradational Events on Mars from Crater Depth and Diameter Measurements [#3286] The study of crater population depths and diameters on Mars suggests that a major degradational event at the end of the Noachian era in the mid-latitudes (but not the high-latitudes), and a relatively recent several hundred meters deduction in topography in the high-latitude.

Seventh International Conference on Mars sess02.pdf

Bridges N. T. Geissler P. G. Thomson B. J. McEwen A. S. Martinez-Alonso S. E. Golombek M. P. Herkenhoff K. E. HiRISE Team Insights on Ancient and Recent Aeolian Activity on Mars as Seen by the HiRISE Camera [#3297] HiRISE data show that sand and maybe granules are moving today. It seems that first-order ripples are fairly immobile, but sand transported in orthogonal directions forms second-order ripples and ventifacts. Bedforms are found in dusty deposits at the summit of Arsia Mons. Brückner J. Dreibus G. Gellert R. d'Uston C. Athena Science Team Chemistry of Martian Surfaces as Determined by the APXS of the Mars Exploration Rovers [#3120] Alpha-Particle X-Ray Spectrometers (APXS) are used to determine the chemical composition of martian soils and rocks at Gusev crater and Meridiani Planum. An overview on the different chemical compositions of the samples encountered is provided. Buczkowski D. L. An Evaluation of Giant Polygons in Utopia Planitia, Mars [#3322] A new evaluation of the giant polygons in Utopia Planitia is performed. Their locations are mapped and their topography and morphology are reexamined. Burger P. V. Shearer C. K. Papike J. J. Karner J. Interpreting Martian Surface Processes Through the Trace Element Chemistry of Jarosite [#3244] This study explores the viability of SIMS to determine the minor, trace and REE chemistry of jarosite in order to better characterize martian surface processes, environments and fluid compositions. Calvin W. M. Shoffner J. D. Pocock J. M. Johnson J. R. Knudson A. T. Rogers D. Glotch T. D. Ruff S. W. Hematite Spherules at Meridiani: Results from MI, Mini-TES and Pancam [#3163] A synthesis of observations of the hematite spherules support their formation as concretions and shows variation as Opportunity has traversed various facies. Carter L. M. Campbell B. A. Watters T. R. Seu R. Phillips R. J. Biccari D. Holt J. W. Leuschen C. J. Plaut J. J. Safaeinili A. Orosei R. Smrekar S. E. Picardi G. Putzig N. E. Egan A. F. Bernardini F. SHARAD Team SHARAD Observations of the Medusae Fossae Formation [#3207] The SHARAD instrument on Mars Reconnaissance Orbiter can be used to look for layering within the Medusae Fossae Formation. We will show current results, including subsurface interfaces beneath thin deposits on the northern boundary of the formation. Chan M. A. Ormö J. Okubo C. H. Seiler W. M. Komatsu G. Linking Multiple Comparison Features in One Terrestrial Analog: Implications for Rock Properties, Geologic Processes, Fluid History, and Possible Extraterrestrial Life on Mars [#3006] The Jurassic Navajo Sandstone contains multiple features similar to the sedimentary record on Mars. Terrestrial analogs provide key constraints and a comparative framework for remotely interpreting martian properties, processes, and history. Chicarro A. F. Mars Express — Clues for a New Geological History of Mars [#3009] The latest discoveries of ESA's Mars Express will be presented, with emphasis on surface morphology, geology and mineralogy, subsurface sounding and gravity anomalies, as well as atmospheric circulation, composition and escape, and the interaction with the solar wind. Coleman M. Processes of Origin and Duration of Growth of Blueberries at Meridiani Planum [#3057] The process behind blueberries needs to be understood. The questions why did they form, and why are they round, can be answered by: chemical energy and radial diffusion. Blueberry growth energy is olivine serpentinization for two possible precursors, FeS or FeO.OH with modeled 830 yrs to grow.

Seventh International Conference on Mars sess02.pdf

Crumpler L. S. McCoy T. Schmidt M. Cabrol N. Physical Volcanology at Gusev Crater, Spirit Rover [#3385] The field geologic transect of volcanic terrains at Gusev crater by the Mars Exploration (MER) rover Spirit has revolutionized our understanding of volcanic processes on Mars. Mars is more diverse and volcanic landforms are more widespread than believed previously. Cushing G. E. Titus T. N. THEMIS/TES Study of the Arsia Mons/Oti Fossae Thermal Anomaly [#3403] THEMIS, TES and MOC data are used with the KRC thermal model to constrain physical properties of the Arsia Mons/Oti Fossae thermal anomaly. Results indicate this is a likely area of dust removal, rather than deposition, in the Tharsis region. Dinwiddie C. L. Grimm R. E. McGinnis R. N. Stillman D. E. Moderately to Poorly Welded Tuff, Bishop, California: Geophysical and Geological Characterization to Determine the Source of Radar Scattering [#3334] We report on analog data obtained from a return trip to pyroclastic deposits near Bishop, CA, to assess the source of scattering in low-frequency radar data. We conclude that a polygonal network of cooling joints is the source of radar scattering. Dunaway J. K. Moersch J. E. Piatek J. L. Thermal Infrared Spectral Variability in the Eastern Tyrrhena Terra Region of Mars [#3340] Eastern Tyrrhena Terra is the focus of a spectroscopic study supplemented by geomorphic data in search of evaporites, olivine relationships to aqueous environments, and relationships of near sub-surface materials and ejecta material composition. Fergason R. L. Christensen P. R. Cyclic Geologic and Climactic Processes in Eastern Arabia Terra, Mars [#3211] Eastern Arabia Terra is currently mantled in a layer of dust, but has been modified by volcanic, fluvial, and aeolian processes in the past. Cyclic dust deposition and cementation events are likely, and high wind shear conditions were also present. Fleischer I. Klingelhöfer G. Schröder C. Rodionov D. Depth Selectivity in MER Mössbauer Spectra and Possible Surface Layers on Gusev Crater Rocks [#3198] The analysis of 6.4 keV and 14.4 keV backscattering Mössbauer spectra yields depth selective information about the investigated sample. This abstracts discusses results from measurements and Monte-Carlo simulations. Fomitchev M. I. Transient Water Ponding in Central Aram Chaos: Indications from MGS MOC and THEMIS Observations [#3001] We report the identification of transient water activity in central Aram Chaos from the analysis of MGS MOC and THEMIS IR images. The observed phenomena include melt water ponding (surface temp 273K) and run-off gully broadening detected in MGS MOC images taken one year apart. Glotch T. D. Kraft M. D. Thermal Transformations of Lepidocrocite and Akaganéite to Hematite: Examination of Possible Precursors to Martian Crystalline Hematite [#3148] We examine the thermal transformation products of the iron oxyhydroxides lepidocrocite and akaganéite and compare their infrared spectral properties to those of martian crystalline hematite. Gondet B. Langevin Y. Bibring J-P. Poulet F. OMEGA/MEx Global Mineralogical Maps [#3185] OMEGA/Mars Express has identified and located the major surface minerals. We will present and discuss the global maps of olivine, pyroxene, phyllosilicate and sulfates.

Seventh International Conference on Mars sess02.pdf

Green R. O. Murchie S. Miliken R. Atmospheric Correction and Analysis of CRISM Full Resolution Target Measurements Using the MODTRAN Radiative Transfer Code [#3338] Atmospheric correction and analysis of CRISM full resolution target measurements using the MODTRAN radiative transfer code. Greenwood J. P. Blake R. E. Barron V. Torrent J. Phosphorus Geochemistry of Mars: Evidence for an Early Acidic Hydrosphere [#3228] Phosphorus geochemistry of martian soils and rocks is shown to be most consistent with an early acidic hydrosphere on Mars. Grotzinger J. P. Depositional Model for the Burns Formation, Meridiani Planum [#3292] Sedimentary rocks at Meridiani were formed by eolian and fluvial sediment transport mechanisms. Emplacement by volcanic or impact processes is not supported by available observations. Harmon J. K. Nolan M. C. Arecibo Radar Imaging of Mars During the 2005 Opposition [#3136] Radar imaging results from Arecibo observations during the 2005 Mars opposition are presented. With an average resolution of 3 km, these are by far the highest quality large-scale radar images of Mars to date. Hauber E. Plains Volcanism on Mars Revisited: The Topography and Morphology of Low Shields and Related Landforms [#3287] The morphology of landforms associated with plains volcanism on Mars is fully consistent with basaltic volcanism on Earth. The flank slopes of low shields are among the lowest in the solar system, indicating a very low viscosity of the lavas. Hurowitz J. A. Taylor G. J. Wyatt M. B. McLennan S. M. Yen A. S. Boynton W. V. A Global View of Martian Weathering Based on Lander, GRS, and MGS-TES Data [#3263] We present combined lander (Viking, Pathfinder, MER), GRS, and derived MGS-TES chemical abundances indicating that low-pH, water-limited alteration processes exert a significant control on the composition of martian soils and rocks on a global scale. Hynek B. M. Rogers K. L. McCollom T. M. Cerro Negro, Nicaragua: A Key Mars Analog Environment for Acid-Sulfate Weathering [#3213] Cerro Negro Volcano, Nicaragua, is being investigated as an analog for acid-sulfate weathering of Mars-like basalts. Our goal is to better understand the mineral alteration pathways and the astrobiological potential of early Mars. Islam F. Cooke M. L. McGill G. E. Analysis of the First-Order Mechanics of Polygonal Fault Networks on Utopia Planitia Using Boundary Element Method Modeling [#3112] The overlap in scale between terrestrial polygons and the giant polygons of Mars suggests they may have similar origins. Volumetric contraction accommodates the extensional faulting observed in both cases. Boundary Element Method modeling investigates this mechanism for Utopia Planitia. Ivanov B. A. Secondary Craters on Mars: A Few New Counts [#3171] Size-frequency distribution of secondary crater (mainly from Zunil) is analyzed for future estimates of the effect of secondary craters on the crater retention age estimates. Jaeger W. L. Keszthelyi L. P. McEwen A. S. Dundas C. M. Russell P. S. The Recent Geologic History of Athabasca Valles, Mars, as Revealed by HiRISE [#3394] HiRISE images show that the youngest outflow channel system on Mars, Athabasca Valles, is draped by lava from a voluminous eruption and peppered by hydrovolcanic cones.

Seventh International Conference on Mars sess02.pdf

Johnson J. B. Hopkins M. A. Kaempfer T. Moore J. M. Sullivan R. J. Richter L. Schmitz N. Athena Science Team Determining Mars Soil Properties from Laboratory Tests, Discrete Element Modelling, and Mars Trenching Experiments [#3186] We report on preliminary comparison of discrete element method (DEM) simulations of laboratory tests of the Mars Exploration Rovers (MER) wheel/soil interaction. These are used to calibrate the DEM to analyze MER data to determine soil properties. Johnson J. R. Thermal Infrared Emissivity Spectra of Experimentally Shocked Andesine [#3258] We are acquiring thermal infrared spectra of experimentally shocked (16–57 GPa) andesine (An36–46) to complement the data previously acquired from the shocked bytownite (An75) and albite (An02) for comparison to martian and sample data. Kargel J. S. Miyamoto H. Furfaro R. Glaciers, Permafrost, and Dry Mass Flows, and Their Striping, Corrugation, and Degradation on Mars and Throughout the Solar System [#3271] Glacial and periglacial flows and ablation etching on Earth and Mars produce similar flow lineations and corrugations; dry mass movements can produce some similar features but they are not etched by ablation. Karunatillake S. Squyres S. Taylor J. Gasnault O. McLennan S. Boynton W. V. The Mars Odyssey Gamma Ray Spectrometer Reveals Chemically Striking Regions on Mars [#3190] The Mars Odyssey GRS has returned mass fractions of Al, Ca, Cl, Fe, H, K, Si, and Th. We define chemically distinct regions on the basis of this data to help elucidate the link between geologic units and the chemical evolution of the martian crust. Keszthelyi L. Jaeger W. L. Milazzo M. P. McEwen A. S. HiRISE Team High Resolution Imaging Science Experiment (HiRISE) Images of Volcanic Terrains from the First 6 Months of the Mars Reconnaissance Orbiter Primary Science Phase [#3314] HiRISE samples volcanoes and lava flows. Kirk R. L. Howington-Kraus E. Rosiek M. R. Cook D. Anderson J. Becker K. Archinal B. A. Keszthelyi L. King R. McEwen A. S. HiRISE Team Ultrahigh Resolution Topographic Mapping of Mars with HiRISE Stereo Images: Methods and First Results [#3381] The HiRISE camera will obtain hundreds of large stereopairs of Mars at 30 cm/pix. We describe the process of generating meter-resolution digital topographic models from these and show early results including the MER rover sites. Kochemasov G. G. Martian Dichotomy Expressed in Relief, Crustal Chemistry, Polar Caps, Atmosphere [#3033] Dichotomy of Mars is developed in relief, density and chemistry of rocks, ice distribution in regolith and polar caps. High standing light southern continents diminish their rock density by inclusion of important amounts of primary salts. Korteniemi J. Raitala J. Ivanov M. Kostama V.-P. Törmänen T. Degraded Mesas on the Eastern Rim of the Hellas Basin, Mars: Remnants of a Larger Massif? [#3281] These mesas show evidence of intense degradation/erosion. They are the source of several fluvial channels, which have been active during a long period of time. We interpret the mesas as possible remnants of an ancient larger glacier-like structure. Kraft M. D. Sharp T. G. Michalski J. R. Rampe E. B. A Pedogenic Weathering Model for the Formation of Silica Coatings on High-Latitude Martian Surfaces [#3396] Silica coatings on basaltic materials can explain thermal and near-infrared observations of the northern plains of Mars. Coatings could form in recent soil environments.

Seventh International Conference on Mars sess02.pdf

Kreslavsky M. A. Statistical Characterization of Spatial Distribution of Impact Craters: Implications to Present-Day Cratering Rate on Mars [#3325] Advanced methods for statistical assessment of spatial randomness of impact craters are presented. Deviation from spatial randomness of new craters found by Malin et al. (2006) demands a factor of 3 correction for cratering rate. Kurita K. Baratoux D. Sato H. Suzuki A. Vaucher J. Kodama S. Ichihara M. Saiki K. Kaneko T. Kimura J. Takahashi S. Nakamura R. Watanabe H. Thermal Imaging of Volcanic Areas and Implications for the Interpretation of Surface Temperatures on Mars [#3113] Our objective is to discriminate the volcanic products on Mars from their thermal properties. We report on a thermal survey of volcanic soils in Japan. Heat conduction alone does not explain all observations. Other sources of heat are suspected. Lane M. D. Bishop J. L. Dyar M. D. Parente M. King P. L. Hyde B. C. The Ferric Sulfate and Ferric Phosphate Minerals in the Light-toned Paso Robles Rover Track Soils: A Multi-Instrument Analysis [#3331] Interpretation of the mineralogy of the Paso Robles bright soil using our VNIR reflectance, TIR emission, and Mössbauer spectral data sets suggests the presence of ferricopiapite and ferric phosphate (possibly ferristrunzite). Le Deit L. Mège D. Bourgeois O. Le Mouélic S. Sotin C. Mangold N. Hauber E. Gendrin A. Bibring J.-P. Morphological and Mineralogical Analysis of East Candor Chasma in Valles Marineris on Mars [#3227] MOLA DEM, HRSC, THEMIS, MOC, HiRISE and OMEGA data are used to study the geomorphology and the mineralogy of East Candor Chasma in order to characterize the geological history of the chasma. Lee S. W. Wolff M. Cantor B. A. MARCI Regional and Global Mapping of Mars [#3386] Global and regional map mosaics, derived from the MARCI instrument, will be presented. Levine J. S. Sulfates, the Absence of Carbonates and the Search for Gases of Volcanic and Biogenic Origin on Mars [#3019] On the order of 1 bar of volcanic sulfur dioxide was released to the atmosphere of Mars during the Tharsis formation. The sulfur dioxide readily formed sulfuric acid, which precipitated out of the atmosphere leading to the destruction of any surface carbonates. Li R. Di K. Wu B. Chen W. Maimone M. W. Matthies L. H. Richter L. Kirk R. Sullivan R. Crumpler L. Parker T. Des Marais D. Arvidson R. Sims M. H. Squyres S. Athena Science Team Over Three Years of Rover Localization and Topographic Mapping for MER 2003 Mission [#3277] This abstract outlines the rover localization and mapping results and products produced over the past three years of operations. Martínez-Alonso S. Mellon M. T. McEwen A. S. HiRISE Team Geological Study of a Section of Aeolis Mensae, a Possible Site Favorable for Life [#3262] High water and Cl contents, a major structural boundary, and elevated spectral variance suggest this locality may be a favorable habitat. Thermophysical, spectral, and morphological data are analyzed to evaluate these observations' significance. McDowell M. L. Hamilton V. E. Examination of Phyllosilicate-bearing Materials in the Vicinity of the Nili Fossae Using Thermal Infrared Data [#3095] We examine THEMIS and TES TIR data in areas OMEGA identified as containing phyllosilicates to better understand the spectral characteristics of phyllosilicate-bearing materials and reliable TES detection limits for modeled phyllosilicate abundances.

Seventh International Conference on Mars sess02.pdf

McEwen A. S. Tornabene L. L. HiRISE Team Modern Mars: HiRISE Observations of Small, Recent Impact Craters [#3086] HiRISE is providing striking new images of very recent impact craters, and there are some surprises relevant to understanding modern processes in addition to cratering. McGovern P. J. Morgan J. K. Smith J. R. Higbie M. A. New Models of Volcanic Spreading and Implications for Azimuthal Variations in the Structure of Olympus Mons, Mars [#3397] We suggest that the tectonic and topographic structure of Olympus Mons is controlled by spatially varying frictional conditions at the base of the edifice, which in turn are established by variations in ancient sediment deposits imposed by regional topography and basement roughness. McGowan E. M. McGill G. E. Spatial Correlation of Putative Water Related Features in Cydonia Mensae and Southern Acidalia Planitia [#3076] This study addresses the distribution of pitted cones and the spatial relationship of pitted cones to putative shorelines located in the Cydonia Mensae-Southern Acidalia Planitia area. Meresse S. Costard F. Mangold N. Masson P. Neukum G. HRSC Team Volcanic Landforms in Hydraotes Chaos: The Role of Magmatism in the Chaotic Terrains Formation [#3127] The origin of the chaotic terrains is still uncertain and varied geologic scenarios have been proposed. The discovery of small rounded volcanic cones with summit pit on the floor of Hydraotes Chaos provide new clues on the chaotic terrains formation. Michalski J. R. Fergason R. Noe Dobrea E. Z. Mangold N. Poulet F. Loizeau D. Constraints on the Origin of Martian Clay Minerals from Thermal Infrared Spectroscopy and Thermal Inertia [#3036] Ancient clay mineral deposits of major geological and astrobiological significance were previously discovered with OMEGA spectral data. We investigate these deposits with TES and THEMIS data to further constrain their mineralogy and geologic origin. Milliken R. E. Grotzinger J. P. Beyer R. A. Murchie S. McEwen A. CRISM Science Team Evidence for Salt Tectonics in Valles Marineris, Mars [#3383] Here we test the hypyothesis that sulfate deposits in Candor and Melas Chasma resulted in salt diapirism and salt-induced tectonics. Moersch J. E. Whisner S. C. Hardgrove C. Thermophysical Characterization of Terrestrial Analogs for Martian Sedimentary Features [#3355] We present initial results of a campaign to characterize spatial patterns of thermal inertias on terrestrial sedimentary features using thermal infrared imaging. Ground truth measurements are correlated with thermal camera and ASTER orbital data. Mouginis-Mark P. J. Tornabene L. L. Boyce J. M. McEwen A. S. Impact Melt and Water Release at Tooting Crater, Mars [#3039] We use HiRISE images to study flows and channels at the morphologically-pristine Tooting Crater, Mars. Flows of impact melt as well as channels interpreted to have formed by dewatering of ejecta are identified, indicating previously unrecognized complexities in cratering events on Mars. Nelson M. J. Newsom H. E. Bullock M. A. Moore J. M. Spilde M. N. Chemical Results for Two Experiments of Minerals Reacted in Mars Aqueous Laboratory Simulations [#3089] This study analyzed mineral grains reacted in chambers with acidic solutions simulating an earlier Mars atmosphere. We found alteration products were produced in a very short time, which has implications for surface processes and chemistry of Mars.

Seventh International Conference on Mars sess02.pdf

Newsom H. E. Crumpler L. S. Reedy R. C. Nelson M. J. Petersen M. T. Evans L. G. Taylor G. J. Keller J. M. Janes D. M. Boynton W. V. Kerry K. E. Dohm J. M. Karunatillake S. Hahn B. C. GRS Team Mars Odyssey Gamma Ray Data Including Calcium: Implications for the Heterogeneity of Martian Surficial Materials and Crustal Evolution [#3284] Mantled areas on the surface have unique chemical compositions, not consistent with the presence of a global homogeneous aeolian layer. Surficial materials also show evidence of locally derived components, and fractionations relative to Mars rocks. Oehler D. Z. Allen C. C. Vernal Crater, SW Arabia Terra: MSL Candidate with Extensively Layered Sediments, Possible Lake Deposits, and a Long History of Subsurface Ice [#3007] Vernal Crater (SW Arabia Terra) is an MSL landing site candidate providing easy access to layered sediments and potential lake deposits. The location is enhanced by a long history of subsurface ice/fluids and association with atmospheric methane. Okubo C. H. Schultz R. A. Nahm A. L. Strength and Deformability of Light-toned Layered Deposits Observed by MER Opportunity: Eagle to Erebus Craters [#3040] The strength and deformability of light-toned layered deposits are estimated based on measurements of porosity from Microscopic Imager data acquired by MER Opportunity during its traverse from Eagle Crater to Erebus Crater. Osterloo M. M. Anderson F. S. Hamilton V. E. Glotch T. D. Characterization and Global Distribution of a New, Spectrally Distinct Surface Feature in Mars Odyssey THEMIS Data [#3269] We investigate a spectrally distinct surface exposed throughout the southern highlands of Mars. We present our initial results on the global distribution as well as a detailed study of an occurrence in Terra Sirenum. Parente M. Bishop J. L. Bell J. F. III Automatic Identification of Dominant Phases and Anomalies in Pancam Images of Gusev Soils [#3390] Automatic spectral unmixing and anomaly detection have enabled us to identify both dominant and low abundance mineral phases consistent with ferric sulfates in several unusual bright region soils uncovered by the rover tracks in Gusev crater. Perl S. M. McLennan S. M. Grotzinger J. P. Herkenhoff K. E. Athena Science Team Sedimentological Constraints on an Infiltrating Paleowater Table in the Burns Formation, Meridiani Planum, Mars [#3298] The purpose of this paper is to use the amount and distribution of secondary pores to constrain the hydrological environment through at least four groundwater recharge events of the Burns formation at Meridiani Planum. Peterson R. C. Nelson W. Madu B. Shurvell H. F. Meridianiite (MgSO4•11H2O): A New Mineral Species Observed on Earth and Predicted to Exist on Mars [#3124] Meridianiite, MgSO4•11H2O, was recently discovered on the surface of a frozen pond in central British Columbia, Canada. Meridianiite is stable below 2°C. Above 2°C it melts incongruently to a slurry of epsomite (MgSO4•7H2O) and water.

Seventh International Conference on Mars sess02.pdf

Pinet P. C. Heuripeau F. Clenet H. Chevrel S. Daydou Y. Baratoux D. Rosemberg C. Bibring J. P. Poulet F. Gondet B. Mustard J. LeMouélic S. Bellucci G. OMEGA Team Mafic Mineralogy Variations Across Syrtis Major Shield and Surroundings as Inferred from Visible-Near-Infrared Spectroscopy by OMEGA/Mars Express [#3146] Various mafic mineralogies are identified across Syrtis Major from both the 1 and 2 µm absorption features monitored by OMEGA, by means of an approach combining Principal Component Analysis (PCA) and Modified Gaussian Modelling (MGM). Rao M. N. Nyquist L. E. Wentworth S. J. Garrison D. H. Herrin J. S. Sutton S. Martian Fluids that Produced Salt Assemblages in Meridiani Rocks and in Martian Meteorites: A Comparison [#3174] Two types of solutions, (a) SO3-high and Cl-low and (b) SO3-low and Cl-high, infiltrated into rocks at Meridiani and had undergone progressive evaporation. Shergottites and nakhlites also interacted with (a)- and (b)- type solutions respectively. Rice M. S. Bell J. F. III Johnson J. R. Hare T. M. Suface Albedo Observations at Gusev Crater and Meridiani Planum, Mars [#3155] We present the full suite of bolometric albedo values measured to date by Spirit and Opportunity along their traverses in Gusev Crater and Meridiani Planum, and compare to estimated bolometric albedo values taken from MOC, IRTM and TES. Safaeinili A. Plaut J. J. Phillips R. J. Seu R. Gim Y. Biccari D. Campbell B. A. Carter L. M. Holt J. W. Leuschen C. J. Orosei R. Picardi G. Smrekar S. E. Putzig N. E. Egan A. F. Fois F. Radio-Transparent Deposits in the Elysium Region of Mars as Observed by MARSIS and SHARAD Radar Sounders [#3206] Both MARSIS and SHARAD provide evidence of an extensive shallow (<300 meter) radio-transparent deposit covering the northern plains of Mars including the Elysium, Amazonis. These deposits are at points up to 75 meters thick in the Elysium region. Salamunićcar G. Lončarić S. Cross-Analysis-based Improvements of Ground Truth Catalogue of Large Martian Craters [#3067] The ground truth (GT) catalogue with 17582 large martian craters, assembled for evaluation of crater detection algorithms, is improved using cross-analysis. The result is more complete GT catalogue with 18711 craters. Salamunićcar G. Lončarić S. Circular-Consistency and Slip-tuning Improvements of Crater Detection Algorithms Based on Gradient Edge Detectors and Radon/Hough Transform [#3066] Six previously implemented crater detection algorithms (CDAs) are improved using some standard and CDA-specific (circular-consistency, slip-tuning) techniques. The results are analyzed using free-response receiver operating characteristics. Saraiva J. Pina P. Bandeira L. Barata T. Baptista A. R. An Automated Tool for Polygonal Pattern Identification on Images of Mars [#3139] We present a methodology for the automated identification of polygonal patterns. It is still in development, but the results of its application show its potential, including the establishment of a classification scheme based on measurable parameters. Seelos F. P. Seelos K. D. Murchie S. L. Mustard J. F. Griffes J. L CRISM Team MRO CRISM Observations of the MSL Candidate Landing Sites [#3168] MRO CRISM is actively supporting MSL landing site selection with dedicated high resolution hyperspectral observations of the candidate landing sites as well as multispectral survey mapping coverage.

Seventh International Conference on Mars sess02.pdf

Simpson R. A. Tyler G. L. Pätzold M. Häusler B. Inference of Electrical and Physical Surface Properties from Mars Express Bistatic Radar [#3044] Bistatic radar echoes at 3.6 cm wavelength were expected to yield estimates of surface dielectric constant smaller than echoes at 13 cm. That has proven not to be true in a surprising number of cases, leading to more complex models for vertical surface structure. Sullivan R. J. Arvidson R. Bell J. F. III Geissler P. Golombek M. Greeley R. Grotzinger J. Herkenhoff K. Johnson J. Jolliff B. Knoll A. Squyres S. W. Thompson S. Whelley P. Weitz C. Insights into Martian Aeolian Processes from Mars Exploration Rovers SPIRIT and OPPORTUNITY [#3049] Aeolian processes at the MER landing site. Swayze G. A. Milliken R. E. Clark R. N. Bishop J. L. Ehlmann B. L. Pelkey S. M. Mustard J. F. Murchie S. L. Brown A. J. MRO CRISM Team Spectral Evidence for Hydrated Volcanic and/or Impact Glass on Mars with MRO CRISM [#3384] MRO CRISM spectra with anomalously wide 2.2 µm absorptions are in some cases attributed to hydrated volcanic or impact glass. Tanaka K. L. Dohm J. M. Hare T. M. Irwin R. P. III Kolb E. J. Skinner J. A. Jr. Mars Geologic Mapping: The Next Generation [#3143] New and improved data, tools, and approaches combine to ensure that the geologic maps of Mars now being assembled, including our global effort, will be much more accurate and useful to scientists and mission planners than their predecessors. Thompson S. D. Calvin W. M. Athena Science Team Stratigraphic Correlation Via Opportunity's Pancam of the Burns Formation, Meridiani Planum, Mars [#3389] This research attempts to correlate the stratigraphy of the Burns Formation via VNIR remote sensing data from the Pancam instrument by classifying spectral information and statistical processing. Tosca N. J. McLennan S. M. The Formation and Stability of Saline Minerals at the Martian Surface [#3134] The geochemical controls on formation and stability of saline minerals at the martian surface are discussed. We focus on both theory and experiment in extracting detailed paleo-environmental information from saline asemblages on Mars. Wang A. Bell J. III Li R. Johnson J. R. Farrand W. Arvidson R. E. Crumpler L. Squyres S. W. Herkenhoff K. Knudson A. Chen W. Athena Team Sulfate-rich Soils Exposed by Spirit Rover at Multiple Locations in Gusev Crater on Mars [#3348] Sulfate-rich soils were exposed by Spirit rover at nine locations around Columbia Hills. The major cation of these sulfates appears reflecting the degree of alterations of regional outcrops and local rocks. Postexposure dehydration may have happened in the salty soils from deeper depth at Tyrone. Wilson L. Head J. W. Dispersal of Tephra in Explosive Eruptions on Mars [#3158] We formulate a new model for explosive eruptions into the atmosphere of Mars; plume behavior below ~20 km altitude is plinian, above Ionian. Home Plate in Gusev may be of explosive volcanic origin; a bomb sag fragment suggests local derivation. Wright S. P. The Basaltic Shergottites: Constraints on Their Existence on Mars, Ejection, and Characteristics (but not Location) of Their Source Region/Crater from Their Geochemistries and Terrestrial Analog Fieldwork [#3399] The locality of shocked basalt in terrestrial ejecta blankets may provide clues on the nature of the ~2.9 Ma basaltic shergottite ejection event.

Seventh International Conference on Mars sess02.pdf

Wyrick D. Y. Smart K. J. The Influence of Mechanical Stratigraphy on Dike-induced Deformation [#3301] The influence of mechanical stratigraphy on graben morphology above igneous dikes is assessed with discrete element models. Results demonstrate that mechanical stratigraphy has a significant effect on surface deformation above a widening dike. Yingst R. A. Schmidt M. E. Herkenhoff K. E. Mittlefehldt D. W. Athena Science Team Linking Home Plate and Algonquin Class Rocks Through Microtextural Analysis: Evidence for Hydrovolcanism in the Inner Basin of Columbia Hills, Gusev Crater [#3296] Microtextural analysis of Algonquin-class and Home Plate rocks indicates a genetic relationship between these two geochemically disparate classes. We conclude that a hydrovolcanic origin for both rock classes is likely. Zealey W. J. Glacial, Periglacial and Glacio-Volcanic Structures on the Echus Plateau, Upper Kasei Vallis [#3002] Sinuous ridges, 270 km long and 200 m high, cross the Hesperian lavas above Echus Chasma. The eastern edge of Echus Plateau is bounded by glacial outwash extending along the edge of Echus Chasma. The presence of volcanic and glacial structures indicates a subglacial volcanic origin for the ridges. Zimbelman J. R. Williams S. H. An Evaluation of Formation Processes for Transverse Aeolian Ridges on Mars [#3047] Field studies have documented topographic profiles across sand ripples, granule ripples, and transverse sand dunes. These data can then be used to assess the likely formation process for transverse aeolian ridges on Mars. Zolotov M. Yu. Mironenko M. V. Formation and Fate of Phyllosilicates on the Surface of Mars: Geochemical Modeling of Aqueous Weathering [#3365] Geochemical modeling of water-rock interaction is used to explore formation conditions of phyllosilicates and their chemical weathering by episodic acid attacks on the surface.

Seventh International Conference on Mars sess02.pdf