DOCSLIB.ORG

Small-Scale Surface Morphology in the Mouth of Ares and Tiu Valles Region from Moc Images

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Small-Scale Surface Morphology in the Mouth of Ares and Tiu Valles Region from Moc Images Lunar and Planetary Science XXXI 1381.pdf SMALL-SCALE SURFACE MORPHOLOGY IN THE MOUTH OF ARES AND TIU VALLES REGION FROM MOC IMAGES. A. G. Cook1, A. T. Basilevsky1, H. Hoffmann2, G. Neukum2, 1Vernadsky Institute, Ko- sygin St. 19, 117975 Moscow, Russia, [email protected], 2DLR Berlin-Adlershof Rutherfordstraße 2, 12489 Berlin-Adlershof, Germany. Introduction: A photogeologic and crater count- island is covered by subparallel benches implying ero- ing study for the mouth of Ares and Tiu Valles, Mars, sion of layered material by water. was made from Viking Orbiter images [1]. The highest There are several wrinkle ridges on the channel resolution image available was 36 m/pixel. Four main floor and islands. The narrow ones are definitely episodes of the valley formation were recognized: 1) younger than the units they are on, however a wrinkle destruction of the cratered plateau and formation of the ridge in the northern part of the image evidently fol- ridged plains, 2) an initial flood that formed high ter- lows an old broad ridge, eroded by a flood (floods). races in Ares and Tiu Valles (IB1) and old fluvial de- Impact craters have been counted in the northern posits (StP and SP), 3) a second flood that formed Ares part of the image. The fact that the density of medium- Vallis floor (CFA) and pitted plains deposits (PP), 4) a sized craters is slightly higher for islands than for the third flood that formed the Tiu Vallis floor (CFT and channel floor probably means preservation of some DP) and, possibly, fractured plains deposits (FP). pre-flood craters within these high areas. Lower den- Newly obtained high-resolution data taken by Mars sity of craters on the hills and within a through could Orbiter Camera (MOC) on board of Mars Global Sur- be explained as a result of destruction of craters by veyor allow us to study the area at resolution 2.5-8 mass-movement and eolian processes. m/pixel. The study of small-scale surface morphology The image 49401 (24.62°N, 32.45°W; 7.82 together with impact crater countings will help us to m/pixel) covers an area, evidently eroded deeply by understand better the genesis of different units and floods, that includes an old 50-km crater, spotted features in the area as well as to clarify the geologic plains (StP), valley terraces (IB1) and the channel floor history of the region. of Tiu Vallis (CFT). The ejecta of the old crater ap- Description of the images under study: Five re- pears to be embayed by StP material. The fact that StP leased high resolution MOC images (44003, 49401, has a scarp towards some part of the ejecta might be 53003-53005), showing different units of the Ares and accounted for wind erosion of the ejecta. Parts of pre- Tiu mouth, were chosen for the photogeologic study. sumably wind-eroded armoring layer can be seen in The image 44003 (18.08°N, 31.37°W; 7.1 m/pixel) several places on the ejecta unit, as well as on the rem- covers a smooth part of the channel floor of Ares Vallis nants of the crater rim. Inside the crater floor there is a (CFA1 in [1] and [2]) and the channel floor with flat-topped 800-m wide mesa. This may suggest ero- grooves and yardang-like ridges (CFA3). This particu- sion of smooth thick layer of deposits within the crater lar morphological type of the channel floor is thought floor. South of the crater bright material mesas are to be related with water erosion of different type of seen. The mesas are probably parts of the StP unit, rocks or alternatively, but less likely, by a later modifi- eroded by later floods. Two or three layers are seen in cation by wind. The study of this new image reduces the scarps of these mesas. Also in few places there are the possibility of eolian origin for the ridges because mesas and hills on the top of the described mesas, sug- they are subparallel to typical fluvial features such as gesting one more layer. In one place the slope looks streamlined islands (IB1) and troughs around some like a sequence of 10-20 subparallel steps which might hills - obstacles on the way of the flood. Only part of be an evidence of layering too. Absence of typical vol- the channel floor within the area is grooved. There also canic landforms in the region favors a sedimentary are smooth plains (CFA1) and terrain with numerous origin for the layers. hollows and mesas covering the slightly higher part of Plains at the bottom of the StP mesas (valley ter- the channel floor in the south. The morphology of the races) are separated with the channel floor (CFT) by a last unit suggests the erosion of an armoring smooth 250-400 m wide furrow. In the middle part of the im- layer and the exposure of a rough lower layer. In few age the furrow almost disappears narrowing down to places there were possibly 3 layers. Similar morphol- 80 m and skirting two hills. Tanaka [3] suggests that ogy can be seen on many high resolution MOC images similar features represent the furrow between debris in different regions of the planet (especially at hill- flows and the valley bank. In the southern part of the tops), suggesting eolian modification. However in the image, a few terrace-like benches are seen on both north part of the image the surface of the streamlined sides of the furrow. We think they may be caused more likely by fluvial erosion, not by a debris flow emplace- Lunar and Planetary Science XXXI 1381.pdf SURFACE MORPHOLOGY OF ARES AND TIU MOUTH: A. G. Cook et al. ment. Many small craters have dark deposits at their following stage of erosion resurfaced both the terrace bottoms in the area; dark spots and parallel ridges are and the ejecta. also seen especially on channel floor and the bottom of The image 53004 (18.67°N, 34.15°; 2.55 m/pixel) the crater suggesting intensive eolian deposition in the is located within the smooth part of the channel floor area. of Tiu Vallis (CFT1), and 70 km south-west (upstream) The image 53003 (15.49°N, 33.68°; 5.87 m/pixel) the Mars Pathfinder landing site. Several terrace-like shows a highly cratered valley terrace (IB1). The valley benches cross the area. These landforms probably slopes are furrowed in the top and very smooth in the formed when the last flood in Tiu Vallis cut the chan- depositional zone at the bottom. The channel floor of nel floor of Ares Vallis. At the bottom of the lower Tiu Vallis is occupied by plains with hollows. Some bench there are a few elongated hollows, possibly other parts of the CFT shows such morphology on the formed by intensive erosion. The morphology of the Viking Images. Newly recognized fissures form here highest bench suggests the erosion of layered rocks. ripple-like patterns at the channel floor perpendicular The image 53005 (25.21°N, 35.11°, 5.08 m/pixel) to paleoflow direction (Fig. 1). These "ripples" could covers relatively young fractured plains (FP). On the be fluvial landforms formed by running water, or fea- MOC image two types of terrains are seen: a relatively tures on the surface of a debris flow, or even a mudflow smooth and bright terrain which has a scarp toward a (if there were one e.g. [3]). In any case "ripples" have darker terrain. The darker plains are covered by nu- been partly eroded, when hollows formed. Surfaces of merous transverse ridges formed by NE wind (like plains with fissures and lower-lying hollows are rela- some dark spots recognized before on Viking images tively rough. In one place it seems that there is a flat- [1]). We think that the scarp lies between the higher toped mesa higher than the plains with ripples. This fractured plains and relatively older lower dark plains could indicate that the "ripples" were first buried and (DP), embayed by fractured plains material. then exhumed. Apart from transverse ridges (especially numerous within the dark plains) there are dunes inside impact craters and differently oriented dark streaks (possibly dust devils tracks). Two small mesas (<180 m wide) within DP may be remnants of eroded units (SP, StP or PP). The entire image is covered by numerous secon- dary craters. Conclusion: The study reveals many morphologi- cal details such as: 1) a wide extension of layered sedimantary rocks in the area, 2) different amounts of impact craters within different units at small scale, 3) There is also a 6-km diameter impact crater, eroded non-uniform distribution of dunes and other eolian by flood(s), within the valley terrace. landforms, 4) the precise position of geologic bounda- Our impact crater counts show that the most cra- ries. The images show possible continuous formation tered area is the terrace (IB1) - most probably the oldest of wrinkle ridges on Ares Valles floor. The morphol- unit. The less cratered areas are hollows on the channel ogy of the longitudinal furrow within Tiu Vallis floor floor, valley slopes and the bottom of the 6-km impact suggests fluvial development rather than debris flow. crater. Probably this is the result of mass movement The differences in the density of small craters within and eolian accumulation. Impact craters look partly various units in general correspond to the possible se- buried on the lower part of the valley slope and the quence of the unit formation and resurfacing.
Load more

Recommended publications
  • 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.
    [Show full text]
  • The 1997 Mars Pathfinder Spacecraft Landing Site: Spillover Deposits
    www.nature.com/scientificreports OPEN The 1997 Mars Pathfnder Spacecraft Landing Site: Spillover Deposits from an Early Mars Inland Sea Received: 13 June 2018 J. A. P. Rodriguez1, V. R. Baker2, T. Liu 2, M. Zarroca3, B. Travis1, T. Hui2, G. Komatsu 4, Accepted: 22 January 2019 D. C. Berman1, R. Linares3, M. V. Sykes1, M. E. Banks1,5 & J. S. Kargel1 Published: xx xx xxxx The Martian outfow channels comprise some of the largest known channels in the Solar System. Remote-sensing investigations indicate that cataclysmic foods likely excavated the channels ~3.4 Ga. Previous studies show that, in the southern circum-Chryse region, their fooding pathways include hundreds of kilometers of channel foors with upward gradients. However, the impact of the reversed channel-foor topography on the cataclysmic foods remains uncertain. Here, we show that these channel foors occur within a vast basin, which separates the downstream reaches of numerous outfow channels from the northern plains. Consequently, foods propagating through these channels must have ponded, producing an inland sea, before reaching the northern plains as enormous spillover discharges. The resulting paleohydrological reconstruction reinterprets the 1997 Pathfnder landing site as part of a marine spillway, which connected the inland sea to a hypothesized northern plains ocean. Our food simulation shows that the presence of the sea would have permitted the propagation of low-depth foods beyond the areas of reversed channel-foor topography. These results explain the formation at the landing site of possible fuvial features indicative of fow depths at least an order of magnitude lower than those apparent from the analyses of orbital remote-sensing observations.
    [Show full text]
  • Downloaded for Personal Non-Commercial Research Or Study, Without Prior Permission Or Charge
    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.
    [Show full text]
  • Bibliography
    Bibliography Acu˜na, M. H., Connerney, J. E. P., Ness, N. F., Lin, R. P., Basilevsky, A. T., Litvak, M. L., Mitrofanov, I. G., Boynton, Mitchell, D., Carlson, C. W., McFadden, J., Anderson, W., Saunders, R. S., and Head, J. W. (2003). Search for K. A., R`eme, H., Mazelle, C., Vignes, D., Wasilewski, P., Traces of Chemically Bound Water in the Martian Surface and Cloutier, P. (1999). Global Distribution of Crustal Layer Based on HEND Measurements onboard the 2001 Magnetization Discovered by the Mars Global Surveyor Mars Odyssey Spacecraft. Solar System Research, 37, MAG/ER Experiment. Science, 284, 790–793. 387–396. Allen, C. C. (1979). Volcano-ice interactions on Mars. J. Geo- Basilevsky, A. T., Rodin, A. V., Kozyrev, A. S., Mitrofanov, phys. Res., 84(13), 8048–8059. I. G., Neukum, G., Werner, S. C., Head, J. W., Boynton, W., and Saunders, R. S. (2004). Mars: The Terra Arabia Anderson, C. E. (1987). An overview of the theory of hy- Low Epithermal Neutron Flux Anomaly. In Lunar and drocodes. Int. J. Impact Eng., 5, 33–59. Planetary Institute Conference Abstracts, page 1091. Basilevsky, A. T., Neukum, G., Ivanov, B. A., Werner, S. K., Arvidson, R. E., Coradini, M., Carusi, A., Coradini, A., Gesselt, S., Head, J. W., Denk, T., Jaumann, R., Hoff- Fulchignoni, M., Federico, C., Funiciello, R., and Sa- mann, H., Hauber, E., and McCord, T. (2005). Morphol- lomone, M. (1976). Latitudinal variation of wind erosion ogy and geological structure of the western part of the of crater ejecta deposits on Mars. Icarus, 27, 503–516. Olympus Mons volcano on Mars from the analysis of the Mars Express HRSC imagery.
    [Show full text]
  • 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].
    [Show full text]
  • Near-Surface Geologic Units Exposed Along Ares Vallis and in Adjacent Areas: a Potential Source of Sediment at the Mars Oz C
    https://ntrs.nasa.gov/search.jsp?R=19970022395 2020-06-16T02:32:22+00:00Z View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by NASA Technical Reports Server NASA-CR-206.689 JOURNAL UI" ut_t .... _CAL RESEARCH, VOL. 102,NO. E2, PAGES 4219-4229, FEBRUARY 25, 1997 Near-surface geologic units exposed along Ares Vallis and in adjacent areas: A potential source of sediment at the Mars Oz C_. <-- Pathfinder landing site Allan H. Treiman Lunar and Planetary Institute, Houston,Texas Abstract. A sequence of layers, bright and dark, is exposed on the walls of canyons, impact craters and mesas throughout the Ares Vallis region, Chryse Planitia, and Xanthe Terra, Mars. Four layers can be seen: two pairs of alternating dark and bright albedo. The upper dark layer forms the top surface of many walls and mesas. The upper dark- bright pair was stripped as a unit from many streamlined mesas and from the walls of Ares Valles, leaving a bench at the top of the lower dark layer, "250 m below the highland surface on streamlined islands and on the walls of Ares Vallis itself. Along Ares Vallis, the scarp between the highlands surface and this bench is commonly angular in plan view (not smoothly curving), suggesting that erosion of the upper dark-bright pair of layers controlled by planes of weakness, like fractures or joints. These near-surface layers in the Ares Vallis area have similar thicknesses, colors, and resistances to erosion to layers exposed near the tops of walls in Valles Marineris [Treiman et al., 1995] and may represent the same pedogenic hardpan units.
    [Show full text]
  • Mars Pathfinder Landing Site Workshop Ii: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington
    /, NASA-CR-200508 L / MARS PATHFINDER LANDING SITE WORKSHOP II: CHARACTERISTICS OF THE ARES VALLIS REGION AND FIELD TRIPS IN THE CHANNELED SCABLAND, WASHINGTON LPI Technical Report Number 95-01, Part 1 Lunar and Planetary Institute 3600 Bay Area Boulevard Houston TX 77058-1113 LPI/TR--95-01, Part 1 "lp MARS PATHFINDER LANDING SITE WORKSHOP II: CHARACTERISTICS OF THE ARES VALLIS REGION AND FIELD TRIPS IN THE CHANNELED SCABLAND, WASHINGTON Edited by M. P. Golombek, K. S. Edgett, and J. W. Rice Jr. Held at Spokane, Washington September 24-30, 1995 Sponsored by Arizona State University Jet Propulsion Laboratory Lunar and Planetary Institute National Aeronautics and Space Administration Lunar and Planetary Institute 3600 Bay Area Boulevard Houston TX 77058-1113 LPI Technical Report Number 95-01, Part 1 LPI/TR--95-01, Part 1 Compiled in 1995 by LUNAR AND PLANETARY INSTITUTE The Institute is operated by the University Space Research Association under Contract No. NASW-4574 with the National Aeronautics and Space Administration. Material in this volume may he copied without restraint for library, abstract service, education, or personal research purposes; however, republication of any paper or portion thereof requires the written permission of the authors as well as the appropriate acknowledgment of this publication. This report may he cited as Golomhek M. P., Edger K. S., and Rice J. W. Jr., eds. ( 1992)Mars Pathfinder Landing Site Workshop 11: Characteristics of the Ares Vallis Region and Field Trips to the Channeled Scabland, Washington. LPI Tech. Rpt. 95-01, Part 1, Lunar and Planetary Institute, Houston. 63 pp.
    [Show full text]
  • Advances in Reconstructing the Geologic History of the Chryse Region Outflow Channels on Mars
    Lunar and Planetary Science XXXV (2004) 1770.pdf ADVANCES IN RECONSTRUCTING THE GEOLOGIC HISTORY OF THE CHRYSE REGION OUTFLOW CHANNELS ON MARS. K. L. Tanaka1 and J. A. Skinner, Jr.2, 1 U.S. Geological Survey, 2255 N. Gemini Dr., Flagstaff, AZ 86001, 2Environmental Geomatics, 719 New Road, Raleigh, NC 27608, [email protected]. Introduction: We have updated our geologic mapping the large outflow channels as well as dissection from of the northern plains of Mars, based on analysis of Mars numerous sinuous channels occurring sporadically Odyssey (MO) Thermal Emission Imaging System throughout the Noachian rocks surrounding Chryse basin. (THEMIS) images and Mars Global Surveyor (MGS) Mars An increasing number of these channels are being Orbiter Laser Altimeter (MOLA) and Mars Orbiter Camera recognized in THEMIS data. (MOC) data. One of our objectives in the mapping has been Chryse unit 2, N(5) = 108±22. This unit embays Chryse the reconstruction of Chryse region outflow channel unit 1 and makes up higher-standing plains outcrops on the activity. Here, we present new findings that bear on margins of Chryse Planitia and is inferred to form some channeling history, the northern plains ocean hypothesis, channel bars in northern Chryse. In northwestern Chryse, and hematite formation in Aram Chaos. the unit appears to be sourced from fractures and troughs Background: The Chryse outflow channels consist near lower Kasei Valles. In southwestern Chryse, the unit primarily of, from west to east, Kasei, Maja, Simud, Tiu, appears to be associated with Maja Valles, including Ares, and Mawrth Valles that debouch into Chryse and secondary channels that spilled over the highland margin at southern Acidalia Planitia (Fig.
    [Show full text]
  • This Article Appeared in a Journal Published by Elsevier
    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 Planetary and Space Science 59 (2011) 1143–1165 Contents lists available at ScienceDirect Planetary and Space Science journal homepage: www.elsevier.com/locate/pss Mars: The evolutionary history of the northern lowlands based on crater counting and geologic mapping à S.C. Werner a, , K.L. Tanaka b, J.A. Skinner Jr.b a Physics of Geological Processes, University of Oslo, Norway b Astrogeology Science Center, U.S. Geological Survey, Flagstaff, Arizona, USA article info abstract Article history: The geologic history of planetary surfaces is most effectively determined by joining geologic mapping Received 15 April 2010 and crater counting which provides an iterative, qualitative and quantitative method for defining Received in revised form relative ages and absolute model ages. Based on this approach, we present spatial and temporal details 18 February 2011 regarding the evolution of the Martian northern plains and surrounding regions. Accepted 29 March 2011 The highland–lowland boundary (HLB) formed during the pre-Noachian and was subsequently Available online 9 April 2011 modified through various processes.
    [Show full text]
  • The GEAS Project: Astronomy Laboratory
    Lab 4 Cratering and the Martian Surface 4.1 Introduction Human space travel enthusiasts hope that our manned missions to the Moon will serve as stepping stones for an eventual trip to Mars. Our “visit” to the Moon in our previous lunar cratering laboratory exercise has prepared us similarly to visit Mars today. We have already learned that cratering is a key process in shaping the appearance of terrestrial planetary surfaces, and that counting craters can help determine the ages of surface features. We studied techniques used to decide which geological event occurred first, or which surface is younger (relative dating techniques), and also learned how to determine absolute ages based on radioactive dating of physical samples. Lunar and Martian surfaces are similar in many ways (both types are heavily cratered in some places and covered with smooth ancient lava flows in others), but they exhibit several important differences. First, volcanic features on Mars are much more prominent than those on the Moon. Mars has the largest volcanoes in the entire solar system, and some of them have clearly become inactive only recently. (Some planetary scientists suspect that the largest Martian volcano of all, Olympus Mons, may still be active today.) Second, unlike the bone-dry Moon, Mars was once a very wet planet. Its surface contains channel and river delta-like features that were undeniably formed by flowing water in the past. These differences lead us to two important questions. When did the last volcanic eruptions occur on Mars, and when did water last flow freely there? In this lab, you’ll use crater counting techniques to help reconstruct a Martian surface chronology and investigate these questions.
    [Show full text]
  • Xanthe Terra Outflow Channel Geology at the Mars Pathfinder Landing Site
    XANTHE TERRA OUTFLOW CHANNEL GEOLOGY AT THE MARS PATHFINDER LANDING SITE. D.M. Nelson, R. Greeley. Department of Geology, Box 871404, Arizona State University, Tempe, Arizona, 85287-1404, USA. E-mail: [email protected] Summary. Geologic mapping of southern Chryse scour features; crater counts suggest an Early Hesperian Planitia and the Xanthe Terra outflow channels has age. Following sheetwash, Mawrth Vallis was formed, revealed a sequence of fluvial events which contributed possibly resulting from the discharge of floods from sediment to the Mars Pathfinder landing site (MPLS). Margaritifer and Iani Chaos. A broad area of subdued Three major outflow episodes are recognized: (1) broad terrain east of Ares Vallis indicates buried and embayed sheetwash across Xanthe Terra during the Early craters to the south of Mawrth Vallis. Floods could Hesperian period, (2) Early to Late Hesperian channel have passed over this surface before excavating Mawrth, formation of Shalbatana, Ravi, Simud, Tiu, and Ares then drained downslope into Acidalia Planitia. Valles, and (3) subsequent flooding which deepened the Alternatively, the subdued area could be a spill zone channels to their current morphologies throughout the formed during the early excavation of Ares Vallis. Late Hesperian. Materials from the most recent Channelization continued in the Late Hesperian with flooding, from Simud and Tiu Valles, and (to a lesser the development of Shalbatana, Ravi, Simud, Tiu, and extent) materials from Ares Vallis, contributed the Ares Valles. Shalbatana Vallis possibly formed by greatest amount of sediment to MPLS. subterranean discharge from Ganges Chasmata [7], and Introduction. Mars Pathfinder landed on Mars July Ravi was excavated by flooding from Aromatum 4, 1997, near the mouths of the outflow channels Ares Chaos.
    [Show full text]
  • Dynamics of Recent Landslides ( A
    Dynamics of recent landslides ( A. Guimpier, S.J. Conway, A. Mangeney, A. Lucas, N. Mangold, M. Peruzzetto, M. Pajola, A. Lucchetti, G. Munaretto, T. Saemundsson, et al. To cite this version: A. Guimpier, S.J. Conway, A. Mangeney, A. Lucas, N. Mangold, et al.. Dynamics of recent landslides ( HAL Id: hal-03287039 https://hal.archives-ouvertes.fr/hal-03287039 Submitted on 15 Jul 2021 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. 1 Dynamics of recent landslides (<20 My) on Mars: Insights from high-resolution 2 topography on Earth and Mars and numerical modelling 3 A. Guimpier1,2*, S. J. Conway1, A. Mangeney3, A. Lucas3, N. Mangold1, M. Peruzzetto3,4, M. Pajola5, 4 A. Lucchetti5, G. Munaretto5,6, T. Sæmundsson 7, A. Johnsson8, L. Le Deit1, P. Grindrod9, J. Davis9, 5 N. Thomas10, G. Cremonese5 6 7 1Laboratoire de Planétologie et Géodynamique, UMR6112 CNRS, Université de Nantes, France 8 2Université Paris-Saclay, France 9 3Université de Paris, Institut de physique du globe de Paris, CNRS, F-75005, Paris France 10 4Bureau de recherches géologiques et
    [Show full text]