DOCSLIB.ORG

The Mcmurdo Dry Valleys of Antarctica As an Analog for Past and Present Martian Surface Processes

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Mcmurdo Dry Valleys of Antarctica As an Analog for Past and Present Martian Surface Processes 51st Lunar and Planetary Science Conference (2020) 1777.pdf THE MCMURDO DRY VALLEYS OF ANTARCTICA AS AN ANALOG FOR PAST AND PRESENT MARTIAN SURFACE PROCESSES. M. R. Salvatore1, J. S. Levy2, J. W. Head3, and J. L. Dickson4, 1Department of Astronomy and Planetary Science, Northern Arizona University, [email protected], 2Dept. of Geology, Colgate University, 3Dept. of Earth, Environmental, and Planetary Sciences, Brown University, 4Division of Geological and Planetary Sciences, Caltech. Introduction: The McMurdo Dry Valleys (MDV) of observed on Mars. We also highlight where additional Antarctica have been considered a valuable martian work in the MDV is necessary to address outstanding analog since the Viking era of Mars exploration [1]. Over questions in martian science. the past two decades, our understanding of martian Cold and Icy Early Mars?: The apparent environmental and geologic evolution has significantly disagreement between observed fluvial and lacustrine improved thanks to the plethora of orbital and landed landforms and the inability for global climate models to missions. New observations have raised many new produce mean annual temperatures greater than 0º C enigmatic questions about how cold and dry geological suggest that the martian surface was possibly never systems evolve, which has revitalized the MDV as an clement from a terrestrial perspective. Instead of a long- important terrestrial analog for Mars, from its earliest lived and continuously active hydrological system on recorded geologic history [2] to the present [3]. early Mars, is it possible that hydrological activity was Global martian climate models struggle to produce more episodic through punctuated climatic excursions on consistently warm and wet conditions at the martian an otherwise cold and icy early Mars? The fluvial and surface early in its history, even with the aid of additional lacustrine systems of the MDV are one possible analog greenhouse gases to offset the distance between Mars and where localized climatic optima drive local hydrological the faint young Sun [4]. Together with studies suggesting systems that can cease once conditions are unfavorable that snowmelt can satisfy the known distribution of [2,12]. The MDV provide compelling evidence for valley networks in parts of the southern highlands [e.g., comparable landforms found in ancient martian 5], these lines of evidence suggest that early Mars may landscapes. It is therefore possible that hydrological have been dominated by relatively cold and dry conditions as opposed to more clement conditions. The hyper-arid and hypo-thermal conditions that dominate the MDV today are some of the most comparable terrestrial conditions to those on modern (cold and dry) Mars [3,6,7] (Fig. 1). Shallow buried ice, glacial processes, and anhydrous oxidative weathering processes are pervasive across both landscapes. More recent work, however, has helped to appreciate the role of locally optimized conditions in driving many surface processes that generate habitable conditions, even in the extremely arid, cold, and radiative environment of the MDV [2]. For example, localized salt concentrations are able to facilitate deliquescence [8], melting of snowpacks and glaciers are facilitated by topographically controlled insolation [9] and, at least in the MDV, microbial ecosystems are able to suspend biological activity indefinitely until conditions are optimal [10]. These cold and dry conditions operate at one end of a hydrological continuum [11] in the MDV--the other end of which is the “cold and wet” endmember--where glacial melt, Fig. 1. Cold desert hydrological landforms on Earth and snow-fed streams, and ice-covered lakes persist, despite Mars. (a) Streams in the MDV. A portion of Quickbird only ~2 months of melting [3,12]. The hydrological and image 101001000AF37000. North is up. (b) Gullies in habitability gradients operating in the MDV make them Wright Valley, Antarctica. Gully fans are ~150 m across. the ideal environment for exploring Mars-like surface (c) Water track in Taylor Valley, Antarctica. Water track processes that have shaped both planets under both is ~2-3 m wide and flows downstream towards image ancient and modern climate conditions [2,3]. bottom. (d) Amazonian valley with flat-topped terminal fan. Portion of HiRISE image PSP_005950_1401. In this work, we highlight the recent developments in North is up. (e) Gullies on Mars. Portion of HiRISE comparative planetology between the martian surface image ESP_021584_1440. North is up. (f) Recurring and the MDV. This work has helped to decipher many slope lineae (RSL) on Mars. Portion of HiRISE image enigmatic climatological and geological features PSP_005787_1475. North is up. 51st Lunar and Planetary Science Conference (2020) 1777.pdf systems present in the MDV, where mean annual A912-A928. [2] Head, J. W., & Marchant, D. R. (2014), temperatures are less than -20º C, can be analogous to Ant. Sci. 26, 774-800. [3] Marchant, D. R., & Head, J. W. those hypothesized to have formed on early Mars. (2007), Icarus 192, 187-222. [4] Wordsworth, R. D. Locally Optimized Conditions at Present: Local (2016), Ann. Rev. Earth Planet. Sci. 44, 381-408. [5] influences of topography, geologic resurfacing, Scanlon, K. E. et al. (2013), GRL 40, 4182-4187. [6] proximity to open water, and the distribution of snow and Doran, P. T. et al. (2002), JGR 107, glaciers play a major role in controlling local doi:10.1029/2001JD002045. [7] Heldmann, J. L. et al. environmental conditions in polar deserts that lack (2013), PSS 85, 53-58. [8] Levy, J. S. et al. (2012), GRL vegetation or other modulating influences [13]. For 39, doi:10.1029/2012GL050898. [9] Dickson, J. L., & example, direct insolation on glacial surfaces can result Head, J. W. (2009), Icarus 204, 63-86. [10] McKnight, in local melting, cascading off of the sides of the glaciers, D. M. et al. (1999), BioSci. 49, 985-995. [11] Levy, J. S. and runoff in ephemeral stream channels along the valley (2015), Geomorph. 240, 70-82. [12] Wlostowski, A. N. walls into the melted margins of perennially frozen lakes et al. (2016), Hydr. Proc. 30, 2958-2975. [13] Lyons, W. [14]. At finer scales, where topographic obstacles result et al. (2000), Fresh. Bio. 43, 355-367. [14] Dickson, J. L. in snow drift formation and subsequent melt et al. (2017), GSL Spec. Pub. 467, doi:10.1144/SP467.4. enhancement, saturated groundwater flow can occur atop [15] Levy, J. S. et al. (2011), GSA Bull. 123, 2295-2311. the permafrost ice table [15]. Finally, local [16] Gough, R. V. et al. (2017), EPSL 476, 189-198. [17] concentrations of salts in soils can deliquesce when Doran, P. T. et al. (2010), relative humidity increases [8,16], resulting in doi:10.1017/CBO9780511712258. hydrological linkages in the absence of well-developed stream channels. In tandem, these hydrological systems that form in seemingly unsuitable geographic and environmental regimes demonstrate how it is possible for local extrema can dominate over global norms. Biological Consequences of Cold Polar Conditions: Biologically simple yet metabolically complex ecosystems are present in the MDV and are dominated by microbial communities, mosses, algae, and microinvertebrates. These ecosystems are fueled by ephemeral glacial and snow melt, ions leached from rocks and soils through chemical weathering, and abundant sunlight during the warmer austral summer. Challenges to the growth and development of these ecosystems include long stretches of dark, subfreezing, and dry conditions centered around the austral winter (e.g., Fig. 2). The fact that biological communities were able to form, live, and adapt to the harsh Antarctic environment provides wishful thinking for life on both ancient and modern Mars as well as a useful guide for looking at the metabolic adaptations of such extreme communities [17]. Implications and Conclusions: The MDV are a unique geological, hydrological, and ecological environment on their own. It is one of the few locations on Earth where a plethora of important variables can be isolated, minimized, or even removed when considering the growth and development of ecosystems. For these reasons, in addition to the cold temperatures and limited availability of liquid water, the MDV are a valuable planetary analog environment. Specifically, the MDV demonstrate how and why locally optimized Fig. 2. An active (a) and inactive dry (b) stream channel environmental conditions can dominate important with orange and black mats within the channel thalweg and along the margins, respectively. Inactive mats geological and ecological processes in Antarctica and brighten and become flaky when desiccated. Both (a) suggests that similar optimized conditions may play and (b) are ~2 m wide. (c) A piece of dry black microbial important roles in the evolution of Mars. mat showing the texture of desiccated mat materials. References: [1] Gibson, E. K. et al. (1983), JGR 88, Image is ~5 cm wide. .
Load more

Recommended publications
  • The Influence of Fцhn Winds on Glacial Lake Washburn And
    Portland State University PDXScholar Geology Faculty Publications and Presentations Geology 3-1-2017 The Influence of öhnF Winds on Glacial Lake Washburn and Palaeotemperatures in the McMurdo Dry Valleys, Antarctica, During the Last Glacial Maximum Maciej Obryk Portland State University Peter Doran Louisiana State University Ed Waddington University of Washington-Seattle Chris McKay NASA Ames Research Center Follow this and additional works at: https://pdxscholar.library.pdx.edu/geology_fac Part of the Geology Commons Let us know how access to this document benefits ou.y Citation Details Obryk M.K., Doran P.T., Waddington E.D., Mckay C.P. 2017. The Influence of öhnF Winds on Glacial Lake Washburn and Palaeotemperatures in the McMurdo Dry Valleys, Antarctica, During the Last Glacial Maximum. Antarctic Science, 29(3)1-11. This Article is brought to you for free and open access. It has been accepted for inclusion in Geology Faculty Publications and Presentations by an authorized administrator of PDXScholar. Please contact us if we can make this document more accessible: [email protected]. Antarctic Science page 1 of 11 (2017) © Antarctic Science Ltd 2017 doi:10.1017/S0954102017000062 The influence of föhn winds on Glacial Lake Washburn and palaeotemperatures in the McMurdo Dry Valleys, Antarctica, during the Last Glacial Maximum M.K. OBRYK1,2, P.T. DORAN2, E.D. WADDINGTON3 and C.P. MCKAY4 1Department of Geology, Portland State University, Portland, OR 97219, USA 2Department of Geology and Geophysics, Louisiana State University, Baton Rouge, LA 70803, USA 3Earth and Space Sciences, University of Washington, Seattle, WA 98195, USA 4Space Science Division, NASA Ames Research Center, Moffett Field, CA 94035, USA [email protected] Abstract: Large glacial lakes, including Glacial Lake Washburn, were present in the McMurdo Dry Valleys, Antarctica, during the Last Glacial Maximum (LGM) despite a colder and drier climate.
    [Show full text]
  • NITROGEN on MARS: INSIGHTS from CURIOSITY. J. C. Stern1 , B. Sutter2, W. A. Jackson3, Rafael Na- Varro-González4, Christopher P
    Lunar and Planetary Science XLVIII (2017) 2726.pdf 1 2 3 NITROGEN ON MARS: INSIGHTS FROM CURIOSITY. J. C. Stern , B. Sutter , W. A. Jackson , Rafael Na- varro-González4, Christopher P. McKay5, Douglas W. Ming6, P. Douglas Archer2, D. P. Glavin1, A. G. Fairen7,8 and Paul R. Mahaffy1. 1NASA GSFC, Code 699, Greenbelt, MD 20771, [email protected], 2Jacobs, NASA Johnson Space Center, Houston, TX 77058, 3Texas Tech University, Lubbock, TX 79409, 4Universidad Nacional Autónoma de México, México, D.F. 04510, Mexico, 5NASA Ames Research Center, Moffett Field, CA 94035, 6NASA Johnson Space Center, Houston TX 77058, 7Centro de Astrobiologia, Madrid, Spain, 8Cornell University, Ithaca, NY 14853 Introduction: Recent detection of nitrate on Mars [1] indicates that nitrogen fixation processes occurred in early martian history. Data collected by the Sample Analysis at Mars (SAM) instrument on the Curiosity Rover can be integrated with Mars analog work in order to better understand the fixation and mobility of nitrogen on Mars, and thus its availability to putative biology. In particular, the relationship between nitrate and other soluble salts may help reveal the timing of nitrogen fixation and post-depositional behavior of nitrate on Mars. In addition, in situ measurements of nitrogen abundance and isotopic composition may be used to model atmospheric conditions on early Mars. Methods: The data presented are from analyses of solid Martian drilled and scooped samples by the Sam- ple Analysis at Mars (SAM) instrument suite on the Mars Science Laboratory (MSL) Curiosity Rover. SAM performs evolved gas analysis (EGA), in which a 3 Figure 1.
    [Show full text]
  • Non-Collider Searches for Stable Massive Particles
    Non-collider searches for stable massive particles S. Burdina, M. Fairbairnb, P. Mermodc,, D. Milsteadd, J. Pinfolde, T. Sloanf, W. Taylorg aDepartment of Physics, University of Liverpool, Liverpool L69 7ZE, UK bDepartment of Physics, King's College London, London WC2R 2LS, UK cParticle Physics department, University of Geneva, 1211 Geneva 4, Switzerland dDepartment of Physics, Stockholm University, 106 91 Stockholm, Sweden ePhysics Department, University of Alberta, Edmonton, Alberta, Canada T6G 0V1 fDepartment of Physics, Lancaster University, Lancaster LA1 4YB, UK gDepartment of Physics and Astronomy, York University, Toronto, ON, Canada M3J 1P3 Abstract The theoretical motivation for exotic stable massive particles (SMPs) and the results of SMP searches at non-collider facilities are reviewed. SMPs are defined such that they would be suffi- ciently long-lived so as to still exist in the cosmos either as Big Bang relics or secondary collision products, and sufficiently massive such that they are typically beyond the reach of any conceiv- able accelerator-based experiment. The discovery of SMPs would address a number of important questions in modern physics, such as the origin and composition of dark matter and the unifi- cation of the fundamental forces. This review outlines the scenarios predicting SMPs and the techniques used at non-collider experiments to look for SMPs in cosmic rays and bound in mat- ter. The limits so far obtained on the fluxes and matter densities of SMPs which possess various detection-relevant properties such as electric and magnetic charge are given. Contents 1 Introduction 4 2 Theory and cosmology of various kinds of SMPs 4 2.1 New particle states (elementary or composite) .
    [Show full text]
  • Perchlorate and Chlorate Biogeochemistry in Ice-Covered Lakes of the Mcmurdo Dry Valleys, Antarctica
    Available online at www.sciencedirect.com Geochimica et Cosmochimica Acta 98 (2012) 19–30 www.elsevier.com/locate/gca Perchlorate and chlorate biogeochemistry in ice-covered lakes of the McMurdo Dry Valleys, Antarctica W. Andrew Jackson a,⇑, Alfonso F. Davila b,c, Nubia Estrada a, W. Berry Lyons d, John D. Coates e, John C. Priscu f a Department of Civil and Environmental Engineering, Texas Tech University, Lubbock, TX 79409, USA b NASA Ames Research Center, Moffett Field, CA 95136, USA c SETI Institute, 189 Bernardo Ave., Suite 100, Mountain View, CA 94043-5203, USA d Byrd Polar Research Center, The Ohio State University, Columbus, OH 43210, USA e Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA f Department of Land Resources & Environmental Sciences, Montana State University, Bozeman, MT 59717, USA Received 15 February 2012; accepted in revised form 5 September 2012; available online 19 September 2012 Abstract À À We measured chlorate (ClO3 ) and perchlorate (ClO4 ) concentrations in ice covered lakes of the McMurdo Dry Valleys À À (MDVs) of Antarctica, to evaluate their role in the ecology and geochemical evolution of the lakes. ClO3 and ClO4 are À À present throughout the MDV Lakes, streams, and other surface water bodies. ClO3 and ClO4 originate in the atmosphere and are transported to the lakes by surface inflow of glacier melt that has been differentially impacted by interaction with soils À À and aeolian matter. Concentrations of ClO3 and ClO4 in the lakes and between lakes vary based on both total evaporative concentration, as well as biological activity within each lake.
    [Show full text]
  • NO ONE KNOWS ABOUT US by Bridget Canning. a Creative Writing
    NO ONE KNOWS ABOUT US By Bridget Canning. A Creative Writing Thesis submitted to the School of Graduate Studies in partial fulfillment of the requirements for the degree of Masters of Arts in English (Creative Writing) Department of English, Memorial University of Newfoundland Abstract: No One Knows about Us is a collection of twelve contemporary short stories. As the title suggests, the characters in each story deal with secrets: relationships, longings, grudges, addictions, and trickery. For them, these secrets are simultaneously overwhelming and futile; their importance within their small worlds reflect a deeper feeling of insignificance in the greater scheme of life in a small city in a northern province hemmed on to the side of a continent. Here are a range of characters and situations set in St. John’s, Newfoundland and Labrador. The stories are mapped out in different areas of the city and move chronologically over a year, starting in fall and ending in late summer. They work together to create a small sample of life in modern-day St. John’s – one that is informed by the influences of history, economy, and weather. i Acknowledgements: This thesis would not have been accomplished without the help of the English department faculty at Memorial such as Robert Finley, Robert Chafe, and especially my thesis advisor, Lisa Moore. Thanks to the Graduate Society for their financial support. Thanks to Jonathan Weir, Deirdre Snook, and the members of the Naked Parade Writing Collective for their guidance and encouragement. ii Contents: 1. Seen, p. 1 2. With Glowing Hearts, p. 19 3.
    [Show full text]
  • Federal Register/Vol. 84, No. 78/Tuesday, April 23, 2019/Rules
    Federal Register / Vol. 84, No. 78 / Tuesday, April 23, 2019 / Rules and Regulations 16791 U.S.C. 3501 et seq., nor does it require Agricultural commodities, Pesticides SUPPLEMENTARY INFORMATION: The any special considerations under and pests, Reporting and recordkeeping Antarctic Conservation Act of 1978, as Executive Order 12898, entitled requirements. amended (‘‘ACA’’) (16 U.S.C. 2401, et ‘‘Federal Actions to Address Dated: April 12, 2019. seq.) implements the Protocol on Environmental Justice in Minority Environmental Protection to the Richard P. Keigwin, Jr., Populations and Low-Income Antarctic Treaty (‘‘the Protocol’’). Populations’’ (59 FR 7629, February 16, Director, Office of Pesticide Programs. Annex V contains provisions for the 1994). Therefore, 40 CFR chapter I is protection of specially designated areas Since tolerances and exemptions that amended as follows: specially managed areas and historic are established on the basis of a petition sites and monuments. Section 2405 of under FFDCA section 408(d), such as PART 180—[AMENDED] title 16 of the ACA directs the Director the tolerance exemption in this action, of the National Science Foundation to ■ do not require the issuance of a 1. The authority citation for part 180 issue such regulations as are necessary proposed rule, the requirements of the continues to read as follows: and appropriate to implement Annex V Regulatory Flexibility Act (5 U.S.C. 601 Authority: 21 U.S.C. 321(q), 346a and 371. to the Protocol. et seq.) do not apply. ■ 2. Add § 180.1365 to subpart D to read The Antarctic Treaty Parties, which This action directly regulates growers, as follows: includes the United States, periodically food processors, food handlers, and food adopt measures to establish, consolidate retailers, not States or tribes.
    [Show full text]
  • In Pdf Format
    lós 1877 Mik 88 ge N 18 e N i h 80° 80° 80° ll T 80° re ly a o ndae ma p k Pl m os U has ia n anum Boreu bal e C h o A al m re u c K e o re S O a B Bo l y m p i a U n d Planum Es co e ria a l H y n d s p e U 60° e 60° 60° r b o r e a e 60° l l o C MARS · Korolev a i PHOTOMAP d n a c S Lomono a sov i T a t n M 1:320 000 000 i t V s a Per V s n a s l i l epe a s l i t i t a s B o r e a R u 1 cm = 320 km lkin t i t a s B o r e a a A a A l v s l i F e c b a P u o ss i North a s North s Fo d V s a a F s i e i c a a t ssa l vi o l eo Fo i p l ko R e e r e a o an u s a p t il b s em Stokes M ic s T M T P l Kunowski U 40° on a a 40° 40° a n T 40° e n i O Va a t i a LY VI 19 ll ic KI 76 es a As N M curi N G– ra ras- s Planum Acidalia Colles ier 2 + te .
    [Show full text]
  • 2016 Proposal
    PROJECT SUMMARY Overview: The McMurdo Dry Valleys, Antarctica, are a mosaic of terrestrial and aquatic ecosystems in a cold desert that support microbial foodwebs with few species of metazoans and no higher plants. Biota exhibit robust adaptations to the cold, dark, and arid conditions that prevail for all but a short period in the austral summer. The MCM-LTER has studied these ecosystems since 1993 and during this time, observed a prolonged cooling phase (1986-2002) that ended with an unprecedented summer of high temperature, winds, solar irradiance, glacial melt, and stream flow (the "flood year"). Since then, summers have been generally cool with relatively high solar irradiance and have included two additional high-flow seasons. Before the flood year, terrestrial and aquatic ecosystems responded synchronously to the cooling e.g., the declines in glacial melt, stream flow, lake levels, and expanding ice-cover on lakes were accompanied by declines in lake primary productivity, microbial mat coverage in streams and secondary production in soils. This overall trend of diminished melt-water flow and productivity of the previous decade was effectively reversed by the flood year, highlighting the sensitivity of this system to rapid warming. The observed lags or opposite trends in some physical and biotic properties and processes illustrated the complex aspects of biotic responses to climate variation. Since then, the conceptual model of the McMurdo Dry Valleys has evolved based on observations of discrete climate-driven events that elicit significant responses from resident biota. It is now recognized that physical (climate and geological) drivers impart a dynamic connectivity among landscape units over seasonal to millennial time scales.
    [Show full text]
  • Monsoonal Circulation of the Mcmurdo Dry Valleys, Ross Sea Region, Antarctica: Signal from the Snow Chemistry Nancy A.N
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by University of Maine The University of Maine DigitalCommons@UMaine Earth Science Faculty Scholarship Earth Sciences 2004 Monsoonal Circulation of the McMurdo Dry Valleys, Ross Sea Region, Antarctica: Signal from the Snow Chemistry Nancy A.N. Bertler Paul Andrew Mayewski University of Maine - Main, [email protected] Peter J. Barrett Sharon B. Sneed Michael J. Handley See next page for additional authors Follow this and additional works at: https://digitalcommons.library.umaine.edu/ers_facpub Part of the Earth Sciences Commons Repository Citation Bertler, Nancy A.N.; Mayewski, Paul Andrew; Barrett, Peter J.; Sneed, Sharon B.; Handley, Michael J.; and Kreutz, Karl J., "Monsoonal Circulation of the McMurdo Dry Valleys, Ross Sea Region, Antarctica: Signal from the Snow Chemistry" (2004). Earth Science Faculty Scholarship. 133. https://digitalcommons.library.umaine.edu/ers_facpub/133 This Conference Proceeding is brought to you for free and open access by DigitalCommons@UMaine. It has been accepted for inclusion in Earth Science Faculty Scholarship by an authorized administrator of DigitalCommons@UMaine. For more information, please contact [email protected]. Authors Nancy A.N. Bertler, Paul Andrew Mayewski, Peter J. Barrett, Sharon B. Sneed, Michael J. Handley, and Karl J. Kreutz This conference proceeding is available at DigitalCommons@UMaine: https://digitalcommons.library.umaine.edu/ers_facpub/133 Annals of Glaciology 39 2004 139 Monsoonal circulation of the McMurdo Dry Valleys, Ross Sea region, Antarctica: signal from the snow chemistry Nancy A. N. BERTLER,1 Paul A. MAYEWSKI,2 Peter J.
    [Show full text]
  • Code of Conduct Mcmurdo Dry Valleys ASMA: Day Trips
    Code of Conduct McMurdo Dry Valleys ASMA: Day Trips Located on Ross Island at Hut Point Peninsula is McMurdo Station, which serves as a transportation and logistics hub for the National Science Foundation-managed United States Antarctic Program. Ross Island is also home to New Zealand’s Scott Base and nine Antarctic Specially Protected Areas, each with its own management plan. Approximately 50 miles northwest and across McMurdo Sound are the virtually ice-free McMurdo Dry Valleys, which were discovered in 1903 by British explorer Robert Falcon Scott. The Dry Valley Antarctic Specially Managed Area (or ASMA) was the first ASMA to be officially recognized under the Protocol on Environmental Protection to the Antarctic Treaty. In June, 2004, the Area was formally designated as a Specially Managed Area. Managed Areas are used to assist in the planning and coordination of activities, to avoid conflicts and minimize environmental impacts. Whether this is your first trip to this important Area or you are a frequent visitor, environmental responsibility is your primary priority. Maintaining the ASMA in its natural state must take precedence. The Antarctic Specially Managed Area supports eleven established facilities and many tent camps each season. Established facilities include camps at Lake Hoare, Lake Bonney, Lake Fryxell, New Harbor, F-6, Bull Pass, Marble Point Refueling Station, Lake Vanda, Lower Wright Valley, the radio repeater stations at Mt. Newall and Cape Roberts. The McMurdo Dry Valleys ecosystem contains geological and biological features that are thousands and, in some cases, millions of years old. Microscopic life in the Dry Valleys constitute some of the most fragile and unique ecological communities on Earth.
    [Show full text]
  • A Review of Sample Analysis at Mars-Evolved Gas Analysis Laboratory Analog Work Supporting the Presence of Perchlorates and Chlorates in Gale Crater, Mars
    minerals Review A Review of Sample Analysis at Mars-Evolved Gas Analysis Laboratory Analog Work Supporting the Presence of Perchlorates and Chlorates in Gale Crater, Mars Joanna Clark 1,* , Brad Sutter 2, P. Douglas Archer Jr. 2, Douglas Ming 3, Elizabeth Rampe 3, Amy McAdam 4, Rafael Navarro-González 5,† , Jennifer Eigenbrode 4 , Daniel Glavin 4 , Maria-Paz Zorzano 6,7 , Javier Martin-Torres 7,8, Richard Morris 3, Valerie Tu 2, S. J. Ralston 2 and Paul Mahaffy 4 1 GeoControls Systems Inc—Jacobs JETS Contract at NASA Johnson Space Center, Houston, TX 77058, USA 2 Jacobs JETS Contract at NASA Johnson Space Center, Houston, TX 77058, USA; [email protected] (B.S.); [email protected] (P.D.A.J.); [email protected] (V.T.); [email protected] (S.J.R.) 3 NASA Johnson Space Center, Houston, TX 77058, USA; [email protected] (D.M.); [email protected] (E.R.); [email protected] (R.M.) 4 NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA; [email protected] (A.M.); [email protected] (J.E.); [email protected] (D.G.); [email protected] (P.M.) 5 Institito de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Mexico City 04510, Mexico; [email protected] 6 Centro de Astrobiología (INTA-CSIC), Torrejon de Ardoz, 28850 Madrid, Spain; [email protected] 7 Department of Planetary Sciences, School of Geosciences, University of Aberdeen, Aberdeen AB24 3FX, UK; [email protected] 8 Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Armilla, 18100 Granada, Spain Citation: Clark, J.; Sutter, B.; Archer, * Correspondence: [email protected] P.D., Jr.; Ming, D.; Rampe, E.; † Deceased 28 January 2021.
    [Show full text]
  • The Roots of a Flood Basalt Province: Expedition to Antarctica
    Travelogue The Roots of a Flood Basalt Province: Expedition to Antarctica Jean H. Bédard Natural Resources Canada, Québec In January 2005, I participated in an Antarctic field mapping workshop with a group of researchers under the leadership of Bruce Marsh (Johns Hopkins University), who had obtained a generous grant from the National Science Foundation (Office of Polar Programs, Geology and Geophysics) covering all field and travel expenses. The focus was the plumb- ing system feeding the continental flood basalts that erupted when the South Atlantic Ocean opened 185 million years ago (Kirkpa- trick Basalts, Ferrar Dolerites, Dufek Intrusion). Flood basalts are important features of the geological record, and their emplacement is one of the mechanisms proposed for mass Group photo taken at McMurdo Station. Front row Sam Mukasa, Dougal Jerram, Taber Hersum. 3rd row: (L to R): Andrew Feustel, Dennis Geist, Tom Fleming, extinction. The subvolcanic intrusions that Karen Harpp, Jean Bédard, Michael Garcia, Dick Alan Boudreau, Dave Elliott, Jill van Tongeren, Justin Naslund, Adam Simon, Bruce Marsh. Not present: feed flood basalts are also important sources Durrell, Amanda Charrier. 2nd row: Jennifer Cooper, George Bergantz, Stu McCallum, Michael Manga, of nickel and platinum-group elements (e.g. Ron Fodor, Scott Paterson, Ed Mathez, Jon Davidson, Simon Katterhorn. Noril’sk). However, despite their importance, many issues about the genesis of cumulate postcumulus textural and chemical reequili- rocks remain unresolved. The origin of cumu- bration, which largely obliterates the evidence late rocks being one of my principal interests, of the early processes, making it difficult to the trip prospectus, published in EOS, decipher how cumulate rocks and associated attracted my attention.
    [Show full text]