Megaflooding on Earth and Mars Edited by Devon M
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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. -
Seasonality and Surface Properties of Slope Streaks
51st Lunar and Planetary Science Conference (2020) 2556.pdf SEASONALITY AND SURFACE PROPERTIES OF SLOPE STREAKS. K. M. Primm, R. H. Hoover, H. H. Kaplan, and D. E. Stillman, Dept. of Space Studies, Southwest Research Institute, 1050 Walnut St. #300, Boulder, CO 80302, USA ([email protected]). Background: Slope streaks are large (up to 200 m Methods: We used images from the High wide, up to a few km long), relatively low-albedo Resolution Imagining Science Experiment (HiRISE) to streaks that occur in the dustiest locations on Mars [1]. study the fading rate of slope streaks, Context Camera They are one of the few currently active and (CTX) to create Digital Terrain Models (DTMs) to widespread geologic processes on the surface of Mars. study the slope angles, and lastly the Compact Many slope streaks have persisted for >15 Mars years Reconnaissance Imaging Spectrometer (CRISM) to and others have been observed to form, but many evaluate the mineralogy of slope streaks and the fewer have been seen to completely fade/disappear surrounding terrain. (e.g., [2]). This inconsistency leads us to believe Results: Preliminary observations show that hypothesize that slope streaks might have different within one area (within a few kms), there are slope formation and fading mechanisms depending on their streaks that completely fade within 1 Mars Year and environment. some that form within that same time frame (Fig. 1). There have been several studies of slope streaks The green circles in Fig. 1B shows the newly formed that examine a combination of parameters: slope angles [1,3], mineralogy [4-6], environmental factors, slope streaks and the red circle show the areas where and seasonality [2,7,8] but none have combined all the slope streaks have completely disappeared. -
Formation of Mangala Valles Outflow Channel, Mars: Morphological Development and Water Discharge and Duration Estimates Harald J
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 112, E08003, doi:10.1029/2006JE002851, 2007 Click Here for Full Article Formation of Mangala Valles outflow channel, Mars: Morphological development and water discharge and duration estimates Harald J. Leask,1 Lionel Wilson,1 and Karl L. Mitchell1,2 Received 24 October 2006; revised 3 April 2007; accepted 24 April 2007; published 4 August 2007. [1] The morphology of features on the floor of the Mangala Valles suggests that the channel system was not bank-full for most of the duration of its formation by water being released from its source, the Mangala Fossa graben. For an estimated typical 50 m water depth, local slopes of sin a = 0.002 imply a discharge of 1 Â 107 m3 sÀ1, a water flow speed of 9msÀ1, and a subcritical Froude number of 0.7–0.8. For a range of published estimates of the volume of material eroded from the channel system this implies a duration of 17 days if the sediment carrying capacity of the 15,000 km3 of water involved had been 40% by volume. If the sediment load had been 20% by volume, the duration would have been 46 days and the water volume required would have been 40,000 km3. Implied bed erosion rates lie in the range 1to12 m/day. If the system had been bank-full during the early stages of channel development the discharge could have been up to 108 m3 sÀ1, with flow speeds of 15 m sÀ1 and a subcritical Froude number of 0.4–0.5. -
Souris R1ve.R Investigation
INTERNATIONAL JOINT COMMISSION REPORT ON THE SOURIS R1VE.R INVESTIGATION OTTAWA - WASHINGTON 1940 OTTAWA EDMOND CLOUTIER PRINTER TO THE KING'S MOST EXCELLENT MAJESTY 1941 INTERNATIONAT, JOINT COMMISSION OTTAWA - WASHINGTON CAKADA UNITEDSTATES Cllarles Stewrt, Chnirmun A. 0. Stanley, Chairman (korge 11'. Kytc Roger B. McWhorter .J. E. I'erradt R. Walton Moore Lawrence ,J. Burpee, Secretary Jesse B. Ellis, Secretary REFERENCE Under date of January 15, 1940, the following Reference was communicated by the Governments of the United States and Canada to the Commission: '' I have the honour to inform you that the Governments of Canada and the United States have agreed to refer to the International Joint Commission, underthe provisions of Article 9 of theBoundary Waters Treaty, 1909, for investigation, report, and recommendation, the following questions with respect to the waters of the Souris (Mouse) River and its tributaries whichcross the InternationalBoundary from the Province of Saskatchewanto the State of NorthDakota and from the Stat'e of NorthDakota to the Province of Manitoba:- " Question 1 In order to secure the interests of the inhabitants of Canada and the United States in the Souris (Mouse) River drainage basin, what apportion- ment shouldbe made of the waters of the Souris(Mouse) River and ita tributaries,the waters of whichcross theinternational boundary, to the Province of Saskatchewan,the State of North Dakota, and the Province of Manitoba? " Question ,$! What methods of control and operation would be feasible and desirable in -
GLOBAL HISTORY of WATER and CLIMATE. M. H. Carr, U.S. Geological Survey, 345 Middlefield Road, Menlo Park CA 94025, USA ([email protected])
Fifth International Conference on Mars 6030.pdf GLOBAL HISTORY OF WATER AND CLIMATE. M. H. Carr, U.S. Geological Survey, 345 Middlefield Road, Menlo Park CA 94025, USA ([email protected]). Introduction: Despite acquisition of superb new ages.(05803,08205, 51304). In addition, areas that altimetry and imagery by Mars Global Surveyor, most appear densely dissected in Viking images commonly aspects of the water and climate story are likely to have poorly organized drainage patterns when viewed remain controversial. The relative roles of surface at the MOC scale (04304, 08905, 09306). Through- runoff and groundwater seepage in the formation of going valleys and an ordered set of tributaries are dif- valley networks are yet to be resolved as are the cli- ficult to discern. These areas more resemble terrestrial matic conditions required for their formation. Simi- thermokarst terrains than areas where fluvial proc- larly, the fate of the floodwaters involved in formation esses dominate. A few areas do, have more typical of the outflow channels remains unresolved. While the fluvial erosion patterns. At 26S, 84W numerous MOC images provide little supporting evidence for closely spaced tributaries feed larger valleys to form a proposed shorelines around an extensive global ocean dense, well integrated valley system (07705). Such [1], the altimetry suggests the presence of a bench at examples, are however, rare. constant altitude around the lowest parts of the north- Debates about the origin of valley networks have ern plains [2]. Here I describe some of the attributes of focused mainly on (1) the role of fluvial erosion versus the channels and valleys as seen in the early MOC other processes, (2) the relative roles of groundwaer images, summarize the evidence for climate change sapping and surface runoff, and (3) the climatic con- on Mars, and discuss some processes that might have ditions required for valley formation. -
Origin of Circular Collapsed Landforms in the Chryse Region of Mars ⇑ Manuel Roda A,B, , Maarten G
Icarus 265 (2016) 70–78 Contents lists available at ScienceDirect Icarus journal homepage: www.journals.elsevier.com/icarus Origin of circular collapsed landforms in the Chryse region of Mars ⇑ Manuel Roda a,b, , Maarten G. Kleinhans b, Tanja E. Zegers b, Rob Govers b a Universitá degli Studi di Milano, Dipartimento di Scienze della Terra, Via Mangiagalli, 34, 20133 Milano, Italy b Universiteit Utrecht, Faculty of Geosciences, Heidelberglaan 2, 3584 CS Utrecht, The Netherlands article info abstract Article history: The quasi-circular collapsed landforms occurring in the Chryse region of Mars share similar morpholog- Received 29 June 2015 ical characteristics, such as depth of collapse and polygonally fractured floors. Here, we present a statis- Revised 20 October 2015 tical analysis of diameter, maximum and minimum depth, and amount of collapse of these features. Accepted 21 October 2015 Based on their morphometric characteristics, we find that these landforms have a common origin. In par- Available online 27 October 2015 ticular, the investigated landforms show diameter-depth correlations similar to those that impact craters of equivalent diameters exhibit. We also find that the observed amount of collapse of the collected fea- Keywords: tures is strongly correlated to their diameter. Furthermore, the linear relation between minimum filling Geological processes and pristine depth of craters, the constant ratio between collapse and the amount of filling and the frac- Ices Impact processes tured and chaotic aspect of the filling agree with melting and subsequent collapse of an ice layer below a Mars, surface sediment layer. This interpretation is consistent with a buried sub-ice lake scenario, which is a non-climatic mechanism for producing and storing abundant liquid water under martian conditions. -
New Chryse and the Provinces
New Chryse and the Provinces The city of New Chryse is actually several connected cities. The Upper City is located on a break in the crater rim, looking down past a steep rock to the Lower City. Inside the da Vinci crater rim lies the Inner City, also known as the Old City – Red Era tunnels and cave shelters, as well as several nanocomposite towers and cupolas on Mona Lys Ridge looking down on the lower parts of the city. The Lower city lies in a valley sloping down to the Harbour City, which fills a crater 20 kilometres to the East. The Harbour City crater is connected to Camiling Bay and the sea through two canyons and is very well protected from both wind and ice. South of the Lower City and Harbour City lies The Slopes, a straight slope into the sea that is covered with sprawl and slums. Mona Lys Ridge is a mixture of palatial estates surrounded by gardens, imposing official imperial buildings and towering ancient structures used by the highest ranks of the Empire. The central imperial administration and especially the Council is housed in the Deimos Needle, a diamondoid tower that together with its sibling the Phobos Needle dominate the skyline. Escalators allow swift and discreet transport down to the lower levels of the city, and can easily be defended by the police force. North of Mona Lys lies a secluded garden city for higher administrators, guild officials and lesser nobility. The Inner City is to a large extent part of Mona Lys, although most of the inhabitants of Mona Lys do not care much for the dusty old tunnels and hidden vaults – that is left to the Guild of Antiquarians who maintain and protect it. -
Formation of Aromatum Chaos, Mars: Morphological Development As a Result of Volcano-Ice Interactions Harald J
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 111, E08071, doi:10.1029/2005JE002549, 2006 Formation of Aromatum Chaos, Mars: Morphological development as a result of volcano-ice interactions Harald J. Leask,1 Lionel Wilson,1 and Karl L. Mitchell1,2 Received 3 August 2005; revised 10 May 2006; accepted 16 May 2006; published 17 August 2006. [1] Morphological examination of the Aromatum Chaos depression on Mars supports earlier suggestions that it is a site of cryosphere disruption and release of pressurized water trapped in an underlying aquifer. We infer that the cause of cryosphere disruption was intrusion of a volcanic sill, confined laterally by earlier intruded dikes, and consequent melting of ice by heat from the sill. The vertical extents and displacements of blocks of terrain on the floor of the depression, together with an estimate of the cryosphere thickness, constrain the vertical extent of ice melting and hence the thickness of the sill (100 m) and the depth at which it was intruded (2–5 km). At least 75% of the volume of material removed from Aromatum Chaos must have been crustal rock rather than melted ice. Water from melted cryosphere ice played a negligible role in creating the depression, the process being dominated by released aquifer water. For sediment loads of 30–40% by volume, 10,500–16,500 km3 of aquifer water must have passed through the depression to carry away rock as entrained sediment and erode the associated Ravi Vallis channel. These required water volumes are 2–3 times larger than the amount of water that could reasonably be contained in aquifers located beneath the area of incipiently collapsed ground to the west of Aromatum Chaos and suggest a much larger water source. -
March 21–25, 2016
FORTY-SEVENTH LUNAR AND PLANETARY SCIENCE CONFERENCE PROGRAM OF TECHNICAL SESSIONS MARCH 21–25, 2016 The Woodlands Waterway Marriott Hotel and Convention Center The Woodlands, Texas INSTITUTIONAL SUPPORT Universities Space Research Association Lunar and Planetary Institute National Aeronautics and Space Administration CONFERENCE CO-CHAIRS Stephen Mackwell, Lunar and Planetary Institute Eileen Stansbery, NASA Johnson Space Center PROGRAM COMMITTEE CHAIRS David Draper, NASA Johnson Space Center Walter Kiefer, Lunar and Planetary Institute PROGRAM COMMITTEE P. Doug Archer, NASA Johnson Space Center Nicolas LeCorvec, Lunar and Planetary Institute Katherine Bermingham, University of Maryland Yo Matsubara, Smithsonian Institute Janice Bishop, SETI and NASA Ames Research Center Francis McCubbin, NASA Johnson Space Center Jeremy Boyce, University of California, Los Angeles Andrew Needham, Carnegie Institution of Washington Lisa Danielson, NASA Johnson Space Center Lan-Anh Nguyen, NASA Johnson Space Center Deepak Dhingra, University of Idaho Paul Niles, NASA Johnson Space Center Stephen Elardo, Carnegie Institution of Washington Dorothy Oehler, NASA Johnson Space Center Marc Fries, NASA Johnson Space Center D. Alex Patthoff, Jet Propulsion Laboratory Cyrena Goodrich, Lunar and Planetary Institute Elizabeth Rampe, Aerodyne Industries, Jacobs JETS at John Gruener, NASA Johnson Space Center NASA Johnson Space Center Justin Hagerty, U.S. Geological Survey Carol Raymond, Jet Propulsion Laboratory Lindsay Hays, Jet Propulsion Laboratory Paul Schenk, -
Abstract STUBBLEFIELD, RASHONDA KIAM. Extensional Tectonics at Alba Mons, Mars
Abstract STUBBLEFIELD, RASHONDA KIAM. Extensional Tectonics at Alba Mons, Mars: A Case Study for Local versus Regional Stress Fields. (Under the direction of Dr. Paul K. Byrne). Alba Mons is a large shield volcano on Mars, the development of which appears to be responsible for tectonic landforms oriented radially and circumferentially to the shield. These landforms include those interpreted as extensional structures, such as normal faults and systems of graben. These structures, however, may also be associated with broader, regional stress field emanating from the volcano-tectonic Tharsis Rise, to the south of Alba Mons and centered on the equator. In this study, I report on structural and statistical analyses for normal faults proximal to Alba Mons (in a region spanning 95–120° W and 14–50° N) and test for systematic changes in fault properties with distance from the volcano and from Tharsis. A total of 11,767 faults were mapped for this study, and these faults were all measured for strike, length, and distance from Alba Mons and Tharsis. Additional properties were qualitatively and quantitatively analyzed within a subset of 62 faults, and model ages were obtained for two areas with crater statistics. Distinguishing traits for each structure population include fault properties such as strike, vertical displacement (i.e., throw) distribution profiles, displacement–length (Dmax/L) scaling, and spatial (i.e., cross-cutting) relationships with adjacent faults with different strikes. The only statistically significant correlation in these analyses was between study fault strike with distance from Tharsis. The lack of trends in the data suggest that one or more geological processes is obscuring the expected similarities in properties for these fault systems, such as volcanic resurfacing, mechanical restriction, or fault linkage. -
Reconstruction of Glacial Lake Hind of Southwestern
Journal of Paleolimnology 17: 9±21, 1997. 9 c 1997 Kluwer Academic Publishers. Printed in Belgium. Reconstruction of glacial Lake Hind in southwestern Manitoba, Canada C. S. Sun & J. T. Teller Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 Received 24 July 1995; accepted 21 January 1996 Abstract Glacial Lake Hind was a 4000 km2 ice-marginal lake which formed in southwestern Manitoba during the last deglaciation. It received meltwater from western Manitoba, Saskatchewan, and North Dakota via at least 10 channels, and discharged into glacial Lake Agassiz through the Pembina Spillway. During the early stage of deglaciation in southwestern Manitoba, part of the glacial Lake Hind basin was occupied by glacial Lake Souris which extended into the area from North Dakota. Sediments in the Lake Hind basin consist of deltaic gravels, lacustrine sand, and clayey silt. Much of the uppermost lacustrine sand in the central part of the basin has been reworked into aeolian dunes. No beaches have been recognized in the basin. Around the margins, clayey silt occurs up to a modern elevation of 457 m, and ¯uvio-deltaic gravels occur at 434±462 m. There are a total of 12 deltas, which can be divided into 3 groups based on elevation of their surfaces: (1) above 450 m along the eastern edge of the basin and in the narrow southern end; (2) between 450 and 442 m at the western edge of the basin; and (3) below 442 m. The earliest stage of glacial Lake Hind began shortly after 12 ka, as a small lake formed between the Souris and Red River lobes in southwestern Manitoba. -
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°.