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Thermal Studies of Martian Channels and Valleys Using Termoskan Data
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 99, NO. El, PAGES 1983-1996, JANUARY 25, 1994 Thermal studiesof Martian channelsand valleys using Termoskan data BruceH. Betts andBruce C. Murray Divisionof Geologicaland PlanetarySciences, California Institute of Technology,Pasadena The Tennoskaninstrument on boardthe Phobos '88 spacecraftacquired the highestspatial resolution thermal infraredemission data ever obtained for Mars. Included in thethermal images are 2 km/pixel,midday observations of severalmajor channel and valley systems including significant portions of Shalbatana,Ravi, A1-Qahira,and Ma'adimValles, the channelconnecting Vailes Marineris with HydraotesChaos, and channelmaterial in Eos Chasma.Tennoskan also observed small portions of thesouthern beginnings of Simud,Tiu, andAres Vailes and somechannel material in GangisChasma. Simultaneousbroadband visible reflectance data were obtainedfor all but Ma'adimVallis. We find thatmost of the channelsand valleys have higher thermal inertias than their surroundings,consistent with previousthermal studies. We show for the first time that the thermal inertia boundariesclosely match flat channelfloor boundaries.Also, butteswithin channelshave inertiassimilar to the plainssurrounding the channels,suggesting the buttesare remnants of a contiguousplains surface. Lower bounds ontypical channel thermal inertias range from 8.4 to 12.5(10 -3 cal cm-2 s-1/2 K-I) (352to 523 in SI unitsof J m-2 s-l/2K-l). Lowerbounds on inertia differences with the surrounding heavily cratered plains range from 1.1 to 3.5 (46 to 147 sr). Atmosphericand geometriceffects are not sufficientto causethe observedchannel inertia enhancements.We favornonaeolian explanations of the overall channel inertia enhancements based primarily upon the channelfloors' thermal homogeneity and the strongcorrelation of thermalboundaries with floor boundaries. However,localized, dark regions within some channels are likely aeolian in natureas reported previously. -
Curiosity's Candidate Field Site in Gale Crater, Mars
Curiosity’s Candidate Field Site in Gale Crater, Mars K. S. Edgett – 27 September 2010 Simulated view from Curiosity rover in landing ellipse looking toward the field area in Gale; made using MRO CTX stereopair images; no vertical exaggeration. The mound is ~15 km away 4th MSL Landing Site Workshop, 27–29 September 2010 in this view. Note that one would see Gale’s SW wall in the distant background if this were Edgett, 1 actually taken by the Mastcams on Mars. Gale Presents Perhaps the Thickest and Most Diverse Exposed Stratigraphic Section on Mars • Gale’s Mound appears to present the thickest and most diverse exposed stratigraphic section on Mars that we can hope access in this decade. • Mound has ~5 km of stratified rock. (That’s 3 miles!) • There is no evidence that volcanism ever occurred in Gale. • Mound materials were deposited as sediment. • Diverse materials are present. • Diverse events are recorded. – Episodes of sedimentation and lithification and diagenesis. – Episodes of erosion, transport, and re-deposition of mound materials. 4th MSL Landing Site Workshop, 27–29 September 2010 Edgett, 2 Gale is at ~5°S on the “north-south dichotomy boundary” in the Aeolis and Nepenthes Mensae Region base map made by MSSS for National Geographic (February 2001); from MOC wide angle images and MOLA topography 4th MSL Landing Site Workshop, 27–29 September 2010 Edgett, 3 Proposed MSL Field Site In Gale Crater Landing ellipse - very low elevation (–4.5 km) - shown here as 25 x 20 km - alluvium from crater walls - drive to mound Anderson & Bell -
Replace This Sentence with the Title of Your Abstract
GEOLOGY OF THE SOUTHERN UTOPIA PLANITIA HIGHLAND-LOWLAND BOUNDARY PLAIN: SECOND YEAR RESULTS AND THIRD YEAR PLAN. J. A. Skinner, Jr., K. L. Tanaka, and T. M. Hare. As- trogeology Team, U. S. Geological Survey, 2255 N. Gemini Drive, Flagstaff, AZ 86001 ([email protected]). Introduction: The southern Utopia highland- pographic uniqueness in order to provide context for lowland boundary (HLB) extends >1500 km westward consistent description. To assist in unit delineation and from Hyblaeus Dorsa to the topographic saddle that description for this map region, we recently submitted separates Isidis and Utopia Planitiae. It contains a nomenclature request to the IAU to uniquely identify bench-like platforms that contain depressions, pitted the region located between Nepenthes Mensae and cones (some organized into arcuate chains and thumb- Amenthes Cavi (Fig. 1). We proposed a name for the print terrain), isolated domes, buried circular depres- 275-km-wide, gently-sloping plain in order to high- sions, ring fractures, polygonal fractures, and other light its high-standing character, relative to the smooth locally- to regionally-dispersed landforms [1-2]. The plain located north of Amenthes Cavi. We also re- objective of this map project is to clarify the geologic quested names for three impact craters in Nepenthes evolution of the southern Utopia Planitia HLB by iden- Mensae and Planum (Fig. 1), each of which have tifying the geologic, structural, and stratigraphic rela- unique ejecta and rim morphologies. tionships of surface materials in MTMs 10237, 15237, 20237, 10242, 15242, 20242, 10247, 15247, and 20247. The project was originally awarded in April, 2007 and is in its final year of support. -
16. Ice in the Martian Regolith
16. ICE IN THE MARTIAN REGOLITH S. W. SQUYRES Cornell University S. M. CLIFFORD Lunar and Planetary Institute R. O. KUZMIN V.I. Vernadsky Institute J. R. ZIMBELMAN Smithsonian Institution and F. M. COSTARD Laboratoire de Geographie Physique Geologic evidence indicates that the Martian surface has been substantially modified by the action of liquid water, and that much of that water still resides beneath the surface as ground ice. The pore volume of the Martian regolith is substantial, and a large amount of this volume can be expected to be at tem- peratures cold enough for ice to be present. Calculations of the thermodynamic stability of ground ice on Mars suggest that it can exist very close to the surface at high latitudes, but can persist only at substantial depths near the equator. Impact craters with distinctive lobale ejecta deposits are common on Mars. These rampart craters apparently owe their morphology to fluidhation of sub- surface materials, perhaps by the melting of ground ice, during impact events. If this interpretation is correct, then the size frequency distribution of rampart 523 524 S. W. SQUYRES ET AL. craters is broadly consistent with the depth distribution of ice inferred from stability calculations. A variety of observed Martian landforms can be attrib- uted to creep of the Martian regolith abetted by deformation of ground ice. Global mapping of creep features also supports the idea that ice is present in near-surface materials at latitudes higher than ± 30°, and suggests that ice is largely absent from such materials at lower latitudes. Other morphologic fea- tures on Mars that may result from the present or former existence of ground ice include chaotic terrain, thermokarst and patterned ground. -
Explosive Lava‐Water Interactions in Elysium Planitia, Mars: Geologic and Thermodynamic Constraints on the Formation of the Tartarus Colles Cone Groups Christopher W
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 115, E09006, doi:10.1029/2009JE003546, 2010 Explosive lava‐water interactions in Elysium Planitia, Mars: Geologic and thermodynamic constraints on the formation of the Tartarus Colles cone groups Christopher W. Hamilton,1 Sarah A. Fagents,1 and Lionel Wilson2 Received 16 November 2009; revised 11 May 2010; accepted 3 June 2010; published 16 September 2010. [1] Volcanic rootless constructs (VRCs) are the products of explosive lava‐water interactions. VRCs are significant because they imply the presence of active lava and an underlying aqueous phase (e.g., groundwater or ice) at the time of their formation. Combined mapping of VRC locations, age‐dating of their host lava surfaces, and thermodynamic modeling of lava‐substrate interactions can therefore constrain where and when water has been present in volcanic regions. This information is valuable for identifying fossil hydrothermal systems and determining relationships between climate, near‐surface water abundance, and the potential development of habitable niches on Mars. We examined the western Tartarus Colles region (25–27°N, 170–171°E) in northeastern Elysium Planitia, Mars, and identified 167 VRC groups with a total area of ∼2000 km2. These VRCs preferentially occur where lava is ∼60 m thick. Crater size‐frequency relationships suggest the VRCs formed during the late to middle Amazonian. Modeling results suggest that at the time of VRC formation, near‐surface substrate was partially desiccated, but that the depth to the midlatitude ice table was ]42 m. This ground ice stability zone is consistent with climate models that predict intermediate obliquity (∼35°) between 75 and 250 Ma, with obliquity excursions descending to ∼25–32°. -
Possible Recessional Moraines in the Nilosyrtis Mensae Region, Mars
50th Lunar and Planetary Science Conference 2019 (LPI Contrib. No. 2132) 3085.pdf POSSIBLE RECESSIONAL MORAINES IN THE NILOSYRTIS MENSAE REGION, MARS. A. Johnsson1, 2 3 1 J. Raack , E. Hauber . Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden ([email protected]), 2Institut für Planetologie, Westfälische Wilhelms-Universität, Münster, Germany. 3Institut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt (DLR), Berlin, Germany. Introduction: Previously, numerous studies re- age is available of the studied landforms. For Earth ported on glacier landforms on Mars such as viscous comparison we used publicly available Google Earth flow features (VVF) [1], glacier-like flows (GLF) [2] images. and lobate debris aprons (LDA) [3] where water-ice is Observations and results: The area is dominated by believed to be present under insulating debris cover fretted terrain, mesas, cliffs and flat floored valleys. [1]. This notion was confirmed by SHARAD meas- The studied north-facing cliff range is ~250 km long urements [4]. In terms of possible glacial erosional and and are a few hundred to a more than a thousand me- depositional landforms most studies have focused on ters in height. The cliff is characterized by deeply in- small-scale moraine-like ridges that are associated to cised valley systems. Here we report observations from gully systems in interior crater environments [e.g., 5], two valleys. large-scale glacier landforms at the equatorial volcanic province [e.g., 6], landforms suggesting basal glacial meltwater processes [7,8] and possible drop-moraines from past CO2 glaciers [9]. In this study we surveyed an area that border areas of known VVF's and GLF's along the dichotomy. -
Mars: a Small Terrestrial Planet
Astron Astrophys Rev (2016) 24:15 DOI 10.1007/s00159-016-0099-5 REVIEW ARTICLE Mars: a small terrestrial planet N. Mangold1 · D. Baratoux2,3 · O. Witasse4 · T. Encrenaz5 · C. Sotin1,6 Received: 29 June 2016 / Published online: 16 November 2016 © The Author(s) 2016. This article is published with open access at Springerlink.com Abstract Mars is characterized by geological landforms familiar to terrestrial geolo- gists. It has a tenuous atmosphere that evolved differently from that of Earth and Venus and a differentiated inner structure. Our knowledge of the structure and evolution of Mars has strongly improved thanks to a huge amount of data of various types (visible and infrared imagery, altimetry, radar, chemistry, etc) acquired by a dozen of missions over the last two decades. In situ data have provided ground truth for remote-sensing data and have opened a new era in the study of Mars geology. While large sections of Mars science have made progress and new topics have emerged, a major question in Mars exploration—the possibility of past or present life—is still unsolved. Without entering into the debate around the presence of life traces, our review develops various topics of Mars science to help the search of life on Mars, building on the most recent discoveries, going from the exosphere to the interior structure, from the magmatic evo- lution to the currently active processes, including the fate of volatiles and especially liquid water. Keywords Mars · Geological evolution · Geophysics · Atmosphere B N. Mangold [email protected] -
A Noachian/Hesperian Hiatus and Erosive Reactivation of Martian Valley Networks
Lunar and Planetary Science XXXVI (2005) 2221.pdf A NOACHIAN/HESPERIAN HIATUS AND EROSIVE REACTIVATION OF MARTIAN VALLEY NETWORKS. R. P. Irwin III1,2, T. A. Maxwell1, A. D. Howard2, R. A. Craddock1, and J. M. Moore3, 1Center for Earth and Planetary Studies, National Air and Space Museum, Smithsonian Institution, MRC 315, 6th St. and Inde- pendence Ave. SW, Washington DC 20013-7012, [email protected], [email protected], [email protected]. 2Dept. of Environmental Sciences, P.O. Box 400123, University of Virginia, Charlottesville, VA 22904, [email protected]. 3NASA Ames Research Center, MS 245-3 Moffett Field, CA 94035-1000, [email protected]. Introduction: Despite new evidence for persistent rary in degraded craters of the southern equatorial lati- flow and sedimentation on early Mars [1−3], it remains tudes. All of these deposits likely formed during the unclear whether valley networks were active over long last stage of valley network activity, which appears to geologic timescales (105−108 yr), or if flows were per- have declined rapidly. sistent only during multiple discrete episodes [4] of Gale crater: Gale crater is an important strati- moderate (≈104 yr) to short (<10 yr) duration [5]. Un- graphic marker between discrete episodes of valley derstanding the long-term stability/variability of valley network activity. Gale retains most of the characteris- network hydrology would provide an important control tics of a fresh impact crater [15]: a rough ejecta blan- on paleoclimate and groundwater models. Here we ket, raised rim, hummocky interior walls, secondary describe geologic evidence for a hiatus in highland crater chains, and a (partially buried) central peak valley network activity while the fretted terrain (Figure 2). -
Ponding, Draining and Tilting of the Cerberus Plains; a Cryolacustrine Origin for the Sinuous Ridge and Channel Networks in Rahway Vallis, Mars J.D
Ponding, draining and tilting of the Cerberus Plains; a cryolacustrine origin for the sinuous ridge and channel networks in Rahway Vallis, Mars J.D. Ramsdale, M.R. Balme, S.J. Conway, C. Gallagher To cite this version: J.D. Ramsdale, M.R. Balme, S.J. Conway, C. Gallagher. Ponding, draining and tilting of the Cerberus Plains; a cryolacustrine origin for the sinuous ridge and channel networks in Rahway Vallis, Mars. Icarus, Elsevier, 2015, 253, pp.256-270. 10.1016/j.icarus.2015.03.005. insu-02274317 HAL Id: insu-02274317 https://hal-insu.archives-ouvertes.fr/insu-02274317 Submitted on 29 Aug 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Icarus 253 (2015) 256–270 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Ponding, draining and tilting of the Cerberus Plains; a cryolacustrine origin for the sinuous ridge and channel networks in Rahway Vallis, Mars ⇑ J.D. Ramsdale a, , M.R. Balme a,b, S.J. Conway a, C. Gallagher c a Dept. Physical Sciences, Open University, Walton Hall, Milton Keynes MK7 6AA, United Kingdom b Planetary Science Institute, Suite 106, 1700 East Fort Lowell, Tucson, AZ, 85719, USA c UCD School of Geography, Planning & Environmental Policy, University College Dublin, Dublin, Ireland article info abstract Article history: Rahway Vallis sits within a shallow basin (the ‘‘Rahway basin’’) in the Cerberus Plains of Mars containing Received 18 June 2014 a branching network of channels converging on the basin floor. -
Investigation of the Global Escarpment, Including the Fretted Terrain, in the Martian Northern Hemisphere
Investigation of the Global Escarpment, including the Fretted Terrain, in the Martian Northern Hemisphere by Benjamin Chad Harrold A thesis submitted to the Graduate Faculty of Auburn University in partial fulfillment of the requirements for the Degree of Master of Science Auburn, Alabama August 9, 2010 Copyright 2010 by Benjamin Chad Harrold Approved by David T. King Jr., Co-Chair, Professor of Geology Luke J. Marzen, Co-Chair, Associate Professor of Geography Lorraine W. Wolf, Professor of Geology Abstract The global escarpment and associated fretted terrain are located in the Martian northern hemisphere. Two competing hypothesis presently in play explain the origin of Mars’ global escarpment. These hypotheses involve endogenic and exogenic processes and both could help explain the extreme topographic difference between the southern highlands and the northern lowlands. The focus of this study, the fretted terrain area of the global escarpment, is a transition zone of mesa-like features located directly north of the global escarpment. With the use of digital imagery analysis, georeferencing of existing maps, and the interpretation of current models, the most plausible origin of the escarpment proposed herein would be an exogenic process, namely a single, mega-scale impact shortly after formation of the planet. The main lines of evidence supporting this favored hypothesis are the modeled elliptical shaped basin, similarities between crustal thickness and topographic elevations, mineralogy, and the orientation and size distribution of the northern fretted terrain. ii Acknowledgments The author would like to thank the members of his thesis committee, Drs. David King, Luke Marzen, and Lorraine Wolf for their unequivocal support and guidance during this project. -
The Mars Global Surveyor Mars Orbiter Camera: Interplanetary Cruise Through Primary Mission
p. 1 The Mars Global Surveyor Mars Orbiter Camera: Interplanetary Cruise through Primary Mission Michael C. Malin and Kenneth S. Edgett Malin Space Science Systems P.O. Box 910148 San Diego CA 92130-0148 (note to JGR: please do not publish e-mail addresses) ABSTRACT More than three years of high resolution (1.5 to 20 m/pixel) photographic observations of the surface of Mars have dramatically changed our view of that planet. Among the most important observations and interpretations derived therefrom are that much of Mars, at least to depths of several kilometers, is layered; that substantial portions of the planet have experienced burial and subsequent exhumation; that layered and massive units, many kilometers thick, appear to reflect an ancient period of large- scale erosion and deposition within what are now the ancient heavily cratered regions of Mars; and that processes previously unsuspected, including gully-forming fluid action and burial and exhumation of large tracts of land, have operated within near- contemporary times. These and many other attributes of the planet argue for a complex geology and complicated history. INTRODUCTION Successive improvements in image quality or resolution are often accompanied by new and important insights into planetary geology that would not otherwise be attained. From the variety of landforms and processes observed from previous missions to the planet Mars, it has long been anticipated that understanding of Mars would greatly benefit from increases in image spatial resolution. p. 2 The Mars Observer Camera (MOC) was initially selected for flight aboard the Mars Observer (MO) spacecraft [Malin et al., 1991, 1992]. -
Durham Research Online
Durham Research Online Deposited in DRO: 27 March 2019 Version of attached le: Published Version Peer-review status of attached le: Peer-reviewed Citation for published item: Orgel, Csilla and Hauber, Ernst and Gasselt, Stephan and Reiss, Dennis and Johnsson, Andreas and Ramsdale, Jason D. and Smith, Isaac and Swirad, Zuzanna M. and S¡ejourn¡e,Antoine and Wilson, Jack T. and Balme, Matthew R. and Conway, Susan J. and Costard, Francois and Eke, Vince R. and Gallagher, Colman and Kereszturi, Akos¡ and L osiak, Anna and Massey, Richard J. and Platz, Thomas and Skinner, James A. and Teodoro, Luis F. A. (2019) 'Grid mapping the Northern Plains of Mars : a new overview of recent water and icerelated landforms in Acidalia Planitia.', Journal of geophysical research : planets., 124 (2). pp. 454-482. Further information on publisher's website: https://doi.org/10.1029/2018JE005664 Publisher's copyright statement: Orgel, Csilla, Hauber, Ernst, Gasselt, Stephan, Reiss, Dennis, Johnsson, Andreas, Ramsdale, Jason D., Smith, Isaac, Swirad, Zuzanna M., S¡ejourn¡e,Antoine, Wilson, Jack T., Balme, Matthew R., Conway, Susan J., Costard, Francois, Eke, Vince R., Gallagher, Colman, Kereszturi, Akos,¡ L osiak, Anna, Massey, Richard J., Platz, Thomas, Skinner, James A. Teodoro, Luis F. A. (2019). Grid Mapping the Northern Plains of Mars: A New Overview of Recent Water and IceRelated Landforms in Acidalia Planitia. Journal of Geophysical Research: Planets 124(2): 454-482. 10.1029/2018JE005664. To view the published open abstract, go to https://doi.org/ and enter the DOI. Additional information: Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.