North Polar Region of Mars: Advances in Stratigraphy, Structure, and Erosional Modification
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Boundary Condition Controls on the High-Sand-Flux Regions of Mars Matthew Chojnacki1, Maria E
https://doi.org/10.1130/G45793.1 Manuscript received 8 November 2018 Revised manuscript received 18 January 2019 Manuscript accepted 20 February 2019 © 2019 The Authors. Gold Open Access: This paper is published under the terms of the CC-BY license. Published online 11 March 2019 Boundary condition controls on the high-sand-flux regions of Mars Matthew Chojnacki1, Maria E. Banks2, Lori K. Fenton3, and Anna C. Urso1 1Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona 85721, USA 2National Aeronautics and Space Administration (NASA) Goddard Space Flight Center, Greenbelt, Maryland 20771, USA 3Carl Sagan Center at the SETI (Search for Extra-Terrestrial Intelligence) Institute, Mountain View, California 94043, USA ABSTRACT DATA SETS AND METHODS Wind has been an enduring geologic agent throughout the history of Mars, but it is often To assess bed-form morphology and dynamics, unclear where and why sediment is mobile in the current epoch. We investigated whether we analyzed images acquired by the High Resolu- eolian bed-form (dune and ripple) transport rates are depressed or enhanced in some areas tion Imaging Science Experiment (HiRISE) cam- by local or regional boundary conditions (e.g., topography, sand supply/availability). Bed- era on the Mars Reconnaissance Orbiter (0.25–0.5 form heights, migration rates, and sand fluxes all span two to three orders of magnitude m/pixel; McEwen et al., 2007; see Table DR1 in across Mars, but we found that areas with the highest sand fluxes are concentrated in three the GSA Data Repository1). Digi tal terrain mod- regions: Syrtis Major, Hellespontus Montes, and the north polar erg. -
OCEANS on MARS. J. W. Head, Department of Geological Sciences, Brown University, Providence, RI 02912 USA (James Head [email protected])
Workshop on Mars 2001 2541.pdf OCEANS ON MARS. J. W. Head, Department of Geological Sciences, Brown University, Providence, RI 02912 USA ([email protected]). Introduction: Understanding water, and its state, mapped contacts are ancient shorelines, then they distribution and history on Mars, is one of the most should also represent the margins of an equipotential fundamental goals of the Mars exploration program. surface, and if no vertical movement has occurred Linked to this goal are the questions of the formation subsequent to their formation, the elevation of each and evolution of the atmosphere, the nature of crustal contact should plot as straight lines. Preliminary accretion and destruction, the history of the cryos- analysis of the first 18 orbits showed that neither phere and the polar regions, the origin and evolution Contact plotted as a straight line, but that Contact 2 of valley networks and outflow channels, the nature of was a closer approximation than Contact 1 [5]. We the water cycle, links to SNC meteorites, and issues have now plotted data from Hiatus phase; SPO1, and associated with water and the possible presence of life SPO2, and later orbits, and produced a topographic in the history of Mars. One of the most interesting map of the northern hemisphere. Contact 1 as pres- aspects of recent discussions about water on Mars is ently observed is not a good approximation of an the question of the possible presence of large standing equipotential surface; variation in elevation ranges bodies of water on Mars in its past history. Here we over several km, an amount exceeding plausible val- outline information on recent investigatios into this ues of post-formation vertical movement. -
SHARAD), Pedestal Craters, and the Lost Martian Layers: Initial Assessments Daniel Cahn Nunes,1 Suzanne E
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 116, E04006, doi:10.1029/2010JE003690, 2011 Shallow Radar (SHARAD), pedestal craters, and the lost Martian layers: Initial assessments Daniel Cahn Nunes,1 Suzanne E. Smrekar,1 Brian Fisher,2 Jeffrey J. Plaut,1 John W. Holt,3 James W. Head,4 Seth J. Kadish,4 and Roger J. Phillips5 Received 6 July 2010; revised 16 December 2010; accepted 24 January 2011; published 19 April 2011. [1] Since their discovery, Martian pedestal craters have been interpreted as remnants of layers that were once regionally extensive but have since been mostly removed. Pedestals span from subkilometer to hundreds of kilometers, but their thickness is less than ∼500 m. Except for a small equatorial concentration in the Medusae Fossae Formation, the nearly exclusive occurrence of pedestal craters in the middle and high latitudes of Mars has led to the suspicion that the lost units bore a significant fraction of volatiles, such as water ice. Recent morphological characterizations of pedestal deposits have further supported this view. Here we employ radar soundings obtained by the Shallow Radar (SHARAD) to investigate the volumes of a subset of the pedestal population, in concert with high‐ resolution imagery to assist our interpretations. From the analysis of 97 pedestal craters we find that large pedestals (diameter >30 km) are relatively transparent to radar in their majority, with SHARAD being able to detect the base of the pedestal deposits, and possess an average dielectric permittivity of 4 ± 0.5. In one of the cases of large pedestals in Malea Planum, layering is detected both in SHARAD data and in high‐resolution imagery of the pedestal margins. -
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MARS GLOBAL GEOLOGIC MAPPING: ABOUT HALF WAY DONE. K.L. Tanaka1, J.M. Dohm2, R. Ir- win3, E.J. Kolb4, J.A. Skinner, Jr.1, and T.M. Hare1. 1U.S. Geological Survey, Flagstaff, AZ, [email protected], 2U. Arizona, Tucson, AZ, 3Smithsonian Inst., Washington, DC, 4Google, Inc., CA. Introduction: We are in the third year of a five-year face appearance and apparent burial of underlying ma- effort to map the geology of Mars using mainly Mars terials in MOLA altimetry and THEMIS infrared and Global Surveyor, Mars Express, and Mars Odyssey imag- visible image data sets. It appears to be tens of meters ing and altimetry datasets. Previously, we have reported thick, similar in thickness of the pedestals underlying on details of project management, mapping datasets (local pedestal craters in the same region [4-5]. Thus, the unit and regional), initial and anticipated mapping approaches, appears to have retreated from a former extent. Prelimi- and tactics of map unit delineation and description [1-2]. nary analysis of crater counts and stratigraphic relations For example, we have seen how the multiple types and suggests that the unit is long-lived, likely emplaced huge quantity of image data as well as more accurate and over multiple episodes. These and other observations detailed altimetry data now available allow for broader and interpretations are the topic of a paper in prepara- and deeper geologic perspectives, based largely on im- tion by Skinner and Tanaka, to be submitted in summer proved landform perception, characterization, and analy- of 2009. sis. Here, we describe mapping and unit delineation re- Remaining work: Mapping tasks that remain in- sults thus far, a new unit identified in the northern plains, clude: (1) delineating and describing Noachian and and remaining steps to complete the map. -
SHARAD Observations of Recent Geologic Features on Mars
EPSC Abstracts Vol. 6, EPSC-DPS2011-1591-1, 2011 EPSC-DPS Joint Meeting 2011 c Author(s) 2011 SHARAD observations of recent geologic features on Mars N. E. Putzig (1), R. J. Phillips (1), J. W. Holt (2), I. B. Smith (2), L. M. Carter (3), and R. Seu (4) for the SHARAD Team. (1) Southwest Research Institute, Colorado, USA ([email protected]), (2) University of Texas at Austin, Texas, USA, NASA Goddard Space Flight Center, Maryland, USA, (4) Sapienza University of Rome, Italy. Abstract NPLD stratigraphy consists of packets of brightly reflective layers alternating with relatively non- The Shallow Radar (SHARAD) instrument on the reflective zones, and these sequences can be Mars Reconnaissance Orbiter (MRO) observes a correlated to orbit cycles, suggesting an age of ~4.2 variety of recent features on Mars, including deposits Ma [2]. In detail, the radar shows unconformities, of water ice at both poles and in the mid-latitudes, either within the reflective sequences or at their boundaries (Fig. 1). A history of alternating periods solid CO2 in the south polar region, and volcanics in the tropics and mid-latitudes. SHARAD’s view of of non-uniform deposition and erosion is recorded by subsurface layers sheds light on the history of these structures. In the upper ~500 m, discontinuities deposition and erosion in these terrains, with that trace to troughs observable at the surface map implications for the cycle of volatile exchange and out paths of trough migration over time. The for recent volcanism. poleward migration and SHARAD-observed thickness variations adjacent to the migration path are consistent with a mechanism of katabatic winds 1. -
Pacing Early Mars Fluvial Activity at Aeolis Dorsa: Implications for Mars
1 Pacing Early Mars fluvial activity at Aeolis Dorsa: Implications for Mars 2 Science Laboratory observations at Gale Crater and Aeolis Mons 3 4 Edwin S. Kitea ([email protected]), Antoine Lucasa, Caleb I. Fassettb 5 a Caltech, Division of Geological and Planetary Sciences, Pasadena, CA 91125 6 b Mount Holyoke College, Department of Astronomy, South Hadley, MA 01075 7 8 Abstract: The impactor flux early in Mars history was much higher than today, so sedimentary 9 sequences include many buried craters. In combination with models for the impactor flux, 10 observations of the number of buried craters can constrain sedimentation rates. Using the 11 frequency of crater-river interactions, we find net sedimentation rate ≲20-300 μm/yr at Aeolis 12 Dorsa. This sets a lower bound of 1-15 Myr on the total interval spanned by fluvial activity 13 around the Noachian-Hesperian transition. We predict that Gale Crater’s mound (Aeolis Mons) 14 took at least 10-100 Myr to accumulate, which is testable by the Mars Science Laboratory. 15 16 1. Introduction. 17 On Mars, many craters are embedded within sedimentary sequences, leading to the 18 recognition that the planet’s geological history is recorded in “cratered volumes”, rather than 19 just cratered surfaces (Edgett and Malin, 2002). For a given impact flux, the density of craters 20 interbedded within a geologic unit is inversely proportional to the deposition rate of that 21 geologic unit (Smith et al. 2008). To use embedded-crater statistics to constrain deposition 22 rate, it is necessary to distinguish the population of interbedded craters from a (usually much 23 more numerous) population of craters formed during and after exhumation. -
THE GEOMETRY of CHASMA BOREALE, MARS USING MARS ORBITER LASER ALTIMETER (MOLA) DATA: a TEST of the CATASTROPHIC OUTFLOW HYPOTHESIS of FORMATION Kathryn E
THE GEOMETRY OF CHASMA BOREALE, MARS USING MARS ORBITER LASER ALTIMETER (MOLA) DATA: A TEST OF THE CATASTROPHIC OUTFLOW HYPOTHESIS OF FORMATION Kathryn E. Fishbaugh1 and James W. Head III1, 1Brown University Box 1846, Providence, RI 02912, [email protected], [email protected] Introduction slumped from the scarp. The profile then drops off, becoming a scarp Chasma Boreale is a large reentrant in the northern polar layered de- with a slope of about 9°. Below the scarp, the surface is smoother, and posits of Mars. The Chasma transects the spiraling troughs which char- beyond this lie dunes which are not visible in Fig. 3a. acterize the polar layered terrain. The origin of Chasma Boreale remains Discussion a subject of controversy. Clifford [1] proposed that the Chasma was Chasma Boreale exhibits some features similar to those associated carved as a result of a jökulhlaup triggered by either breach of a crater with terrestrial jökulhlaup events. Single flood events on Earth show a containing basal meltwater or by basal melting due to a hot spot beneath variety of flood conditions, and outburst floods also exhibit several flood the cap. Benito et al. [2] suggest an origin in which catastrophic outflow peaks [5] which could explain the irregular nature of the Chasma floor, is triggered by sapping caused by a tectono-thermal event. A similar the discontinuity of terracing, and the non-uniform profile shape. The origin is proposed for Chasma Australe in the Martian southern polar asymmetry of the floor at the base of the walls in (Fig. 2 b) could be due cap [3]. -
INVESTIGATING the ORIGIN of GYPSUM in OLYMPIA UNDAE: CHARACTERIZING the MINERALOGY of the BASAL UNIT. E. Das1, J. F. Mustard1 and J
52nd Lunar and Planetary Science Conference 2021 (LPI Contrib. No. 2548) 2390.pdf INVESTIGATING THE ORIGIN OF GYPSUM IN OLYMPIA UNDAE: CHARACTERIZING THE MINERALOGY OF THE BASAL UNIT. E. Das1, J. F. Mustard1 and J. D. Tarnas1,2, 1Department of Earth, Environmental and Planetary Sciences, Brown University, Providence RI 02912 ([email protected]), 2Jet Propulsion Laboratory, California Institute of Technology Introduction: The Olympia Undae Sand Sea, near eigenvectors derived from the Hysime algorithm [10] the North Polar ice cap, contains the largest known and determines the independent components of the deposit of gypsum discovered on Mars [1]. The mixed system. 2) Dot Product Mapping: The dot formation of gypsum requires liquid water, hinting that products of the image cube with individual it formed in the North Polar region under circumstances eigenvectors, specifically those containing interesting vastly different from today’s Martian environment. The spectral features, are obtained to highlight regions presence of gypsum in the late Amazonian age dunes, within the image cube where the target mineral may likely sourced from materials of the late Hesperian- have a strong spectral signal. The 3rd eigenvector along early/mid-Amazonian ages [2], are consistent with with its associated dot product map of a subset of wetter periods during these ages. Since the discovery of CRISM image (HRL00003084) over Olympia Undae gypsum in the north polar dunes, various hypotheses are shown in Figure 1. The 3rd eigenvector was chosen have been suggested for its source. One hypothesis as it contained prominent spectral features similar to the suggested formation from in-situ aqueous alteration of target mineral gypsum. -
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MacArtney, Adrienne (2018) Atmosphere crust coupling and carbon sequestration on early Mars. PhD thesis. http://theses.gla.ac.uk/9006/ Copyright and moral rights for this work are retained by the author A copy can be downloaded for personal non-commercial research or study, without prior permission or charge This work cannot be reproduced or quoted extensively from without first obtaining permission in writing from the author The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the author When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given Enlighten:Theses http://theses.gla.ac.uk/ [email protected] ATMOSPHERE - CRUST COUPLING AND CARBON SEQUESTRATION ON EARLY MARS By Adrienne MacArtney B.Sc. (Honours) Geosciences, Open University, 2013. Submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at the UNIVERSITY OF GLASGOW 2018 © Adrienne MacArtney All rights reserved. The author herby grants to the University of Glasgow permission to reproduce and redistribute publicly paper and electronic copies of this thesis document in whole or in any part in any medium now known or hereafter created. Signature of Author: 16th January 2018 Abstract Evidence exists for great volumes of water on early Mars. Liquid surface water requires a much denser atmosphere than modern Mars possesses, probably predominantly composed of CO2. Such significant volumes of CO2 and water in the presence of basalt should have produced vast concentrations of carbonate minerals, yet little carbonate has been discovered thus far. -
This Article Appeared in a Journal Published by Elsevier. the Attached
(This is a sample cover image for this issue. The actual cover is not yet available at this time.) This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier’s archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright Author's personal copy Aeolian Research 8 (2013) 29–38 Contents lists available at SciVerse ScienceDirect Aeolian Research journal homepage: www.elsevier.com/locate/aeolia Review Article Summary of the Third International Planetary Dunes Workshop: Remote Sensing and Image Analysis of Planetary Dunes, Flagstaff, Arizona, USA, June 12–15, 2012 ⇑ Lori K. Fenton a, , Rosalyn K. Hayward b, Briony H.N. Horgan c, David M. Rubin d, Timothy N. Titus b, Mark A. Bishop e,f, Devon M. Burr g, Matthew Chojnacki g, Cynthia L. Dinwiddie h, Laura Kerber i, Alice Le Gall j, Timothy I. Michaels a, Lynn D.V. Neakrase k, Claire E. Newman l, Daniela Tirsch m, Hezi Yizhaq n, James R. Zimbelman o a Carl Sagan Center at the SETI Institute, 189 Bernardo Ave., Suite 100, Mountain View, CA 94043, USA b United States Geological Survey, Astrogeology Science Center, 2255 N. -
Dark Dunes on Mars
CHAPTER II: PLANET MARS – THE BACKGROUND Like Earth, its neighbour planet, Mars, is a terrestrial planet with a solid surface, an atmosphere, two ice-covered pole caps, and not one but two moons (Phobos and Deimos). Some differences, such as a greater distance to the sun, a smaller diameter, a thinner atmosphere, and the longer duration of a year distinguish Mars from the Earth, not to forget the absence of life…so far. Nevertheless, there are many correlations between terrestrial and Martian geological and geomorphological processes, permitting researchers to apply knowledge from terrestrial studies more or less directly to Mars. However, a closer look reveals that the dissimilarities, though few, can make fundamental differences in process background and development. The following chapter provides a brief but necessary insight into the geological and physical background of this planet, imparting to the reader some fundamental knowledge about Mars, which is useful for understanding this work. Fig. 1 presents an impression of Mars viewed from space. Figure 1: The planet Mars: a global view (Viking 1 Orbiter mosaic [NASA]). Chapter II Planet Mars – The Background 5 Table 1 provides a summary of some major astronomical and physical parameters of Mars, giving the reader an impression of the extent to which they differ from terrestrial values. Table 1: Parameters of Mars [Kieffer et al., 1992a]. Property Dimension Orbit 227 940 000 km (1.52 AU) mean distance to the Sun Diameter 6794 km Mass 6.4185 * 1023 kg 3 Mean density ~3.933 g/cm Obliquity -
Mars Ice Detection and Mapping from an Orbital Synthetic Aperture Radar
NEAR-SURFACE ICE, TRANSIENT WATER RELEASES, AND THE GEOLOGIC CONTEXT OF HYDRATED MINERAL EXPOSURES: SAMPLE RETURN AND HUMAN EXPLORATION BENEFITS OF AN ORBITAL IMAGING RADAR FOR MARS Imaging radar offers the spatial resolution of a camera with much greater depth of penetration. Bruce Campbell, John Grant, Jeff Plaut, Tony Freeman, Eagle Discovery Team October 11, 2012 Hidden Landforms and Geologic Context Radar is an imaging sensor that can map geologic landforms beneath mantling sediment to reveal volcanic history, the context of hydrated mineral outcrops, and the role and fate of water. Earth-based 12.6-cm radar view (left) of Elysium Planitia lava flow patterns through dust cover, and 70-cm view (right) of rugged lava flows hidden by 4-8 m of regolith in Mare Serenitatis. DECADAL: What is the geologic record of climate change? How do the polar layered deposits and layered sedimentary rocks record the present-day and past climate and the volcanic and orbital history of Mars? Complementing Radar Sounding MARSIS and SHARAD detect radar reflections from subsurface geologic interfaces, from about 30 m to a few km beneath the surface, in a profiling mode with few-km spatial footprints. An orbital imaging radar would reveal geologic features and ice beneath 3-5 m or more of mantling material, covering large regions with spatial resolution as fine as THEMIS VIS data. Operated in a nadir mode, the same system could sound the upper 100 m of the PLD to complete our understanding of layering and physical properties. A New Landscape Arecibo view of the northern mid-latitudes at 12.6 cm wavelength Harmon et al., Icarus, 2012 A radar in orbit will have 50-100X finer spatial resolution, and about 5X greater depth of penetration.