DOCSLIB.ORG

Iron Terraces in Acid Mine Drainage Systems

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Iron Terraces in Acid Mine Drainage Systems Iron terraces in acid mine drainage systems: A discussion about the organic and inorganic factors involved in their formation through observations from the Tintillo acidic river (Riotinto mine, Huelva, Spain) Javier Sánchez España* Esther Santofi mia Pastor Enrique López Pamo Unidad de Recursos Minerales y Geoambiente, Instituto Geológico y Minero de España (IGME), Rios Rosas, 23, 28003, Madrid, Spain ABSTRACT of TIFs, whereas abiotic parameters, such as and internal structure of such iron terraces, via water composition, fl ow rate and velocity, or extracellular and intracellular assimilation of Iron terraces that form in acidic mine stream channel geometry, also appear to be iron and other metals. Further, TIFs have been drainage settings are unique and extreme essential variables. proposed as modern analogs for ancient (Pre- geomicrobiological systems that can provide cambrian) banded iron formations (BIF) of the highly relevant information about the inter- Keywords: acid mine waters, acidophilic mi- geological record (Hasiotis et al., 2001; Brake action between microbes and their surround- crobes, iron, terraced formations, Tintillo River, et al., 2002), as well as for the Proterozoic and ing aqueous environments. These singular Riotinto. present-day stromatolite-building colonies of systems can represent, additionally, poten- cyanobacteria (Leblanc et al., 1996; Brake et al., tial models for the study of ancient geologi- INTRODUCTION AND SCOPES 2002, 2004), and they have also been considered cal formations (e.g., banded iron formations, by other authors as terrestrial equivalents of the stromatolites) and/or for the cycling of iron The presence of ferruginous terraces of milli- iron oxide deposits recently discovered on Mars on Mars. This work describes geochemical, metric to metric scale is probably the most strik- (Fernández-Remolar et al., 2004). However, mineralogical, morphological, and micro- ing feature observed in acid mine drainage set- the relative importance of the microbial activ- biological evidence obtained in the highly tings worldwide. These terraced iron formations ity with respect to inorganic processes, such as acidic and Fe-rich Tintillo River (Riotinto (TIFs) are usually developed during the oxida- water composition, Fe(III) precipitation rate, mines, Huelva, SW Spain), which can be tion and hydrolysis/precipitation of dissolved stream fl ow velocity, or channel geometry, has used to speculate about the origin and nature iron in the acidic solutions after they emerge not yet been evaluated. A further and critical of the terraced iron formations (TIFs) that from waste piles, tailings, or mine portals, and question arises about whether the formation of are being currently formed in acid mine they display a morphological pattern similar to these ocherous terraces is determined by param- drainage environments. The size (up to 36 m that observed in calcareous travertines formed eters such as stream channel geometry or fl ow 2+ – long and 1 m thick) and continuity (strong in Ca -HCO3 –rich spring waters. TIFs differ velocity, or if, on the other hand, they control the development over 3.5 km) of the iron ter- from calcareous travertines, however, in their evolution of such parameters. races offer a unique opportunity to study mineralogical composition, which is character- The Tintillo River (Huelva, SW Spain) is the different organic (mainly microbial) and ized by hydrous iron (oxy)hydroxides and/or probably a world-class example of an acid mine inorganic processes involved in the construc- hydroxysulfates (Sánchez-España et al., 2005a, drainage–impacted stream in the sense that it tion of these characteristic, travertine-like, 2005b, 2005c), in agreement with the typical is almost entirely formed by highly acidic and 2– sedimentary structures. Evidence presented Fe(II)/Fe(III)-SO4 chemical composition of metal-rich acid mine drainage solutions ema- in this study suggests that both types of pro- most acid mine drainage solutions (Nordstrom nating from waste piles located near the Corta cesses appear to be controlling factors in the and Alpers, 1999). Atalaya open pit (Riotinto Mines; Fig. 1). This formation and internal arrangement of the TIFs have been, until now, the subject of stream course shows chemical, physical, and TIFs, although no defi nitive evidence has little scientifi c attention. The most remarkable microbiological features that seem to favor the been found to support the prevalence of any studies available in the literature have been development of these travertine-like, ferrugi- of these mechanisms with respect to another. focused on the acid mine drainage systems of nous deposits (Sánchez-España et al., 2005a, The photosynthetic production of dissolved the Carnoulés Pb-Zn mine, France (Leblanc et 2005c). For example, it has: oxygen by eukaryotic microorganisms (green al., 1996; Casiot et al., 2004) and the Green Val- (1) initially near-anoxic water with a high algae, euglenophytes, and diatoms) and the ley coal mine, Indiana, USA (Brake et al., 2001, concentration of dissolved ferrous iron (on the Fe-oxidizing metabolism of acidophilic pro- 2002, 2004; Hasiotis et al., 2001). From this order of 2 g/L Fe[II]) at the source point; karyotes are critical factors for the formation research, it is apparent that microbes (including (2) an initially turbulent fl ow near the source acidophilic bacteria and eukaryotic microor- point (downslope of the waste pile) with succes- *[email protected]. ganisms) play a critical role in the construction sive, centimeter-scale water falls that promote Geosphere; June 2007; v. 3; no. 3; p. 133–151; doi: 10.1130/GES00069.1; 13 fi gures; 2 tables. For permission to copy, contact [email protected] 133 © 2007 Geological Society of America Downloaded from http://pubs.geoscienceworld.org/gsa/geosphere/article-pdf/3/3/133/865180/i1553-040X-3-3-133.pdf by guest on 28 September 2021 Sánchez España et al. Figure 1. Confi guration of the Tintillo acidic river (in red) and its main tributaries (in blue). For simplifi cation, only spring a is shown in the source area. The locations of water and terraced iron formation (TIF) samples are also indicated. water oxygenation and enhance the oxidation work emphasizes the organic versus inorganic Huelva province (Fig. 1). This river is mainly of Fe(II); origin of these structures and presents results fed by leachates of acid mine drainage ema- (3) abundant mat-forming, benthic communi- that include: (1) the chemical composition of nating from the base of large, sulfi de-bearing, ties of acidophilic, Fe-oxidizing bacteria, which the stream waters and its downstream evolution, waste-rock piles and tailings impoundments have colonized the stream substrate and appear (2) the major morphological, mineralogical, and situated in the surroundings of Corta Atalaya, a to enhance the oxidation of Fe(II); chemical characteristics of the TIFs, and (3) the vast open pit exploited from 1907 to 1991 by (4) a considerable initial fl ow rate of between spatial (downward) evolution of living benthic the company Minas de Riotinto. At the head- 15 and 30 L/s; and microbes (algal and bacterial colonies) and their waters of the river, there are a number of small (5) an initial pH around 2.6–2.8, which permits relation to the aqueous chemistry and TIF devel- acid mine drainage springs (named as spring a, the hydrolysis/precipitation of aqueous Fe(III). opment. Finally, we hypothesize about the origin spring b, etc.), which have variable fl ow rates on As a result of such favorable geochemical, of TIFs by comparisons with similar acid mine the order of a few liters per second and which hydrodynamic, and microbiological condi- drainage systems, as well as calcareous traver- fi nally converge in the T-1 sampling point (Sán- tions, spectacular terraces of decametric scale tines formed in carbonate-rich environments. chez-España et al., 2005c). Subsequently, the have formed along the fi rst 3.5 km of the river Tintillo River meets some tributaries (the Gan- (Fig. 2). ENVIRONMENTAL SETTING gosa and Escorial creeks; Fig. 1), which are also The present study is aimed at providing fur- acidic and show comparable fl ow rates but lesser ther insight into the development of TIFs in acid Location and Hydrological Confi guration sulfate and metallic content. Finally, the Tintillo mine drainage systems through preliminary of the Tintillo Acidic River River converges with the Odiel River, causing hydrogeochemical, morphological, mineral- a strong environmental impact on the latter and ogical, and microbiological fi ndings from the The Tintillo River is 10 km in length and a sharp decrease of its water quality (Sánchez- exceptional Tintillo acidic river. Particularly, this drains an area of 57 km2 in the northern part of España et al., 2005c, 2006a). 134 Geosphere, June 2007 Downloaded from http://pubs.geoscienceworld.org/gsa/geosphere/article-pdf/3/3/133/865180/i1553-040X-3-3-133.pdf by guest on 28 September 2021 on 28 September 2021 by guest Downloaded from http://pubs.geoscienceworld.org/gsa/geosphere/article-pdf/3/3/133/865180/i1553-040X-3-3-133.pdf Geosphere, June2007 135 A B C Iron terraces in acid mine drainage: Organic vs. inorganic factors in the Tintillo River Tintillo inthe factors vs.inorganic Organic inacidminedrainage: terraces Iron 3 m D E F 3 m 0.5 m 2 m Figure 2. Terraced iron formations (TIFs) of the Tintillo acidic river. (A–B) Panoramic views show- G H ing the general aspect of the Tintillo stream course and its iron terraces, as seen from sampling points T-3 (A) and T-4 (B). (C–D) Fan-shaped deposit of ocherous iron oxides, which form terraces made of consecutive pools and rims. These pictures cor- respond to the same site (stream reach between T-2 and T-3) but were taken at different times: C is from 2004, when the downstream fl ow of water along the terraces provoked the development of continuous centimeter-scale waterfalls (the water fl ow is from left to right of the photograph), while D is from 0.5 m 2 m 2005, when the fl ow had been diverted, after several heavy rainfall events, to the left margin of the river, thus causing the abandonment of the terraces.
Load more

Recommended publications
  • Selection of the Insight Landing Site M. Golombek1, D. Kipp1, N
    Manuscript Click here to download Manuscript InSight Landing Site Paper v9 Rev.docx Click here to view linked References Selection of the InSight Landing Site M. Golombek1, D. Kipp1, N. Warner1,2, I. J. Daubar1, R. Fergason3, R. Kirk3, R. Beyer4, A. Huertas1, S. Piqueux1, N. E. Putzig5, B. A. Campbell6, G. A. Morgan6, C. Charalambous7, W. T. Pike7, K. Gwinner8, F. Calef1, D. Kass1, M. Mischna1, J. Ashley1, C. Bloom1,9, N. Wigton1,10, T. Hare3, C. Schwartz1, H. Gengl1, L. Redmond1,11, M. Trautman1,12, J. Sweeney2, C. Grima11, I. B. Smith5, E. Sklyanskiy1, M. Lisano1, J. Benardino1, S. Smrekar1, P. Lognonné13, W. B. Banerdt1 1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 2State University of New York at Geneseo, Department of Geological Sciences, 1 College Circle, Geneseo, NY 14454 3Astrogeology Science Center, U.S. Geological Survey, 2255 N. Gemini Dr., Flagstaff, AZ 86001 4Sagan Center at the SETI Institute and NASA Ames Research Center, Moffett Field, CA 94035 5Southwest Research Institute, Boulder, CO 80302; Now at Planetary Science Institute, Lakewood, CO 80401 6Smithsonian Institution, NASM CEPS, 6th at Independence SW, Washington, DC, 20560 7Department of Electrical and Electronic Engineering, Imperial College, South Kensington Campus, London 8German Aerospace Center (DLR), Institute of Planetary Research, 12489 Berlin, Germany 9Occidental College, Los Angeles, CA; Now at Central Washington University, Ellensburg, WA 98926 10Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996 11Institute for Geophysics, University of Texas, Austin, TX 78712 12MS GIS Program, University of Redlands, 1200 E. Colton Ave., Redlands, CA 92373-0999 13Institut Physique du Globe de Paris, Paris Cité, Université Paris Sorbonne, France Diderot Submitted to Space Science Reviews, Special InSight Issue v.
    [Show full text]
  • Corvallis Library Purchase Request
    Corvallis Library Purchase Request Is Axel detective or beguiling when circumcise some gnotobiote reroute abroach? Unspectacled Montgomery sometimes loiteringly.wimbling his quietness where'er and perceives so quaintly! Lubberly Ashish expropriated his hoodwinker hurry-skurry Sabetti said she puts together care packages for west orange, corvallis library records were rarely held accountable _ even if new title announcement follows other names of conduct the shoe Full text of newspapers, wire services, and magazines from around the world, including the New York Times. Thursday in a crater on the red planet named after their small village. The content of the video is graphic. Or top with chopped chives and serve warm as a side for dinner! Just bring any borrowed items back on time to avoid any overdue or lost item fees! We do not have a record of materials checked out and returned, unless you have specifically requested that we keep your loan history on file. Indeed may be compensated by these employers, helping keep Indeed free for jobseekers. There will be extensive health and safety measures in place. NASA wants Perseverance snooping around Jezero Crater, once home to a lake fed by a river. Whiteside Theatre Haunted History Tours. Limit one transaction per customer per day. Rainfall around a quarter of an inch. Click the help icon above to learn more. Are we alone in this sort of vast cosmic desert, just flying through space, or is life much more common? Does it just emerge whenever and wherever the conditions are ripe? Friends of the Library members get to check out the sale a day early.
    [Show full text]
  • Planer Och Budget 2011 Budget Och Planer 2010:778 ANP
    Planer och budget 2011 ANP 2010:778 Ved Stranden 18 DK-1061 Köpenhamn K www.norden.org Nordiska ministerrådet Planer och budget 2011 ANP 2010:778 ISBN 978-92-893-2160-0 ANP2010778 omslag.indd 1 10-12-2010 13:54:00 Nordiska ministerrådet Planer och budget 2011 ANP 2010:778 Nordiska ministerrådet Planer och budget 2011 ANP 2010:778 © Nordiska ministerrådet, Köpenhamn 2010 ISBN 978-92-893-2160-0 Tryck: ARCO GRAFISK A/S Omslag: Scanad Upplaga: 600 Tryckt på miljövänligt papper som uppfyller kraven i den nordiska miljösvanemärkningen. Publikationen kan beställas på www.norden.org/order. Fler publikationer på www.norden.org/publikationer Printed in Denmark Nordiska ministerrådet Nordiska rådet Ved Stranden 18 Ved Stranden 18 DK-1061 Köpenhamn K DK-1061 Köpenhamn K Telefon (+45) 3396 0200 Telefon (+45) 3396 0400 Fax (+45) 3396 0202 Fax (+45) 3311 1870 www.norden.org Det nordiska samarbetet Det nordiska samarbetet är ett av världens mest omfattande regionala samarbeten. Det omfattar Danmark, Finland, Island, Norge och Sverige samt de självstyrande områdena Färöarna, Grönland och Åland. Det nordiska samarbetet är politiskt, ekonomiskt och kulturellt förankrat och är en viktig partner i europeiskt och internationellt samarbete. Den nordiska gemenskapen arbetar för ett starkt Norden i ett starkt Europa. Det nordiska samarbetet vill styrka nordiska och regionala intressen och värderingar i en global omvärld. Gemensamma värderingar länderna emellan bidrar till att stärka Nordens ställning som en av världens mest innovativa och konkurrenskraftiga regioner. NSK/MR-SAM BESLUTNING 02.11.2010 Nordisk Ministerråd godkender, med forbehold for de nationale parlamenters godkendelse, vedlagte budget for år 2011 på totalt 896,355 MDKK (2010-prisniveau).
    [Show full text]
  • Let's Get Going!
    June 2014 • Green Valley Recreation News Page 1 June 2014 Volume 12 • No. 6 • 16 Pages www.gvrec.org Pool Hours - All Let’s Get Going! pools open from During the past five 5:30am to 9:00pm months, my time as CEO has Children’s Swim been instructive, education- hours are 11am to al, inspiring, and yes, at times challenging. A few recurring 1pm and 4pm to 6pm themes serve as guideposts daily at all pools. and reinforce what I know to be true. West Center Pool is First of all, all GVR mem- the Family Swim Pool. bers – including me - have a Children’s Hours at foundational commonality. We are property owners in West Center Pool are GVR deed-restricted neigh- NOON to 9pm weekdays borhoods, and regardless of our level of participation in and 5:50am to 9pm on GVR’s plethora of recreation weekends and holidays. and leisure service opportu- nities, we want our property Lastly, I observe and recog- values to remain strong and nize that patience is a virtue, rise. especially when there is so Secondly, at some point in much to do. There is a time our lives, we learned the val- to innovate and pursue new Attend A Concert! ue of recreation and leisure opportunities, and a time to Tickets on Sale as an indicator of quality of wait. life and wellbeing, and its im- I am pleased to update Now! See the Arts & portance to maintaining civil GVR Members regarding Entertainment Section! societies and communities of the 11-Point GVR Work Plan wellbeing.
    [Show full text]
  • A Day in the Life of a TALGV Dog by Rusty - As Told to Jennifer Symons
    Vol. XXVII, Issue 1 A Newsletter for the Friends and Supporters of The Animal League of Green Valley Spring 2013 A Day in the Life of a TALGV Dog by Rusty - as told to Jennifer Symons Welcome to the dog side of TALGV! A man and a woman, and they both I’ve been asked to lead you through a want to walk with me. As they put on day in the life of a TALGV dog and I’m the leash, the woman pets my nose and happy to obey. I’m a dog; I like says its beautiful. How nice of her to having a job. notice. A TALGV morning starts with lights on, On the walk, the TALGV person asks doors opening, and the arrival of them to bring their dog in to meet me, today’s pack of humans. One of them too. The man whispers that they’ll see comes into my run with a leash. “Sit,” me tomorrow. Are these my new she says. It’s the training game. We people? play it every day at TALGV, and with all Back inside, the day changes again. that practice, I know “sit,” “stay,” Visitors are gone and TALGV people are “come,” and usually “leave it.” Right doing paperwork and more cleanup. now, I just want to go on my morning (They’re very fond of cleaning here.) walk, and I do mean right now! Time for peace and quiet, and supper My run has an outside room—I sit in will come soon. I can almost smell it the sun a lot—but these walks are now.
    [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]
  • Phoenix Mission to Mars Will Search for Climate Clues 22 May 2008
    Phoenix mission to Mars will search for climate clues 22 May 2008 On May 25, 2008, approaching 5 p.m. PDT, NASA Phoenix will touch down in Green Valley with the scientists will be wondering: Just how green is their aid of a parachute, retro rockets and three strong valley? That's because at that time the Phoenix legs with shock absorbing footpads to slow it Mars Mission space vehicle will be touching down down. on its three legs to make a soft landing onto the northern Mars terrain called Green Valley. That's sol (a Martian day) zero. Of course, no valley is actually green on the Red "We'll know within two hours of landing if Phoenix Planet. The place got its name after analysis of landed nominally," said Arvidson. "It will land, images from Mars Reconnaissance Orbiter's deploy its solar panels, take a picture and then go HiRISE instrument. HiRISE can image rocks on to bed." Mars as small as roughly a yard and a half across. Green is the color that that landing site selection The next day, Sol 1, begins a crucial period of team used to represent the fewest number of rocks operations for the mission. Arvidson said, "We'll be in an area, corresponding to a desirable place to checking out the instruments and begin robotic arm land. Thus, "green valley," a relatively rock-less operations within about a week, if everything goes region, is a "sweet spot" where the Phoenix well, and collect soil and ice samples over the spacecraft will land.
    [Show full text]
  • Phoenix–Thefirst Marsscout Mission
    Phoenix – The First Mars Scout Mission Barry Goldstein Jet Propulsion Laboratory, California Institute of Technology Pasadena CA [email protected] Robert Shotwell Jet Propulsion Laboratory, California Institute of Technology [email protected] Abstract —1 2As the first of the new Mars Scouts missions, 4) Characterize the history of water, ice, and the polar the Phoenix project was select ed by NASA in August of climate. Determine the past and present biological potential 2003. Four years later, almost to the day, Phoenix was of the surface and subsurface environments. launched from Cape Canaveral Air Station and successfully injected into an interplanetary trajectory on its way to Mars. TABLE OF CONTENTS On May 25, 2008 Phoenix conducted the first successful 1. INTRODUCTION ..................................................... 1 powered decent on Mars in over 30 years. This paper will 2. DEVELOPMENT PHASE ACTIVITIES ..................... 3 highlight some of the key changes since the 2008 IEEE 3. ENTRY DESCENT & LANDING MATURITY .......... 11 paper of the same name, as well as performance through 4. CONCLUSION ....................................................... 18 cruise, landing at the north pole of Mars and some of the REFERENCES ........................................................... 19 preliminary results of the surface mission. BIOGRAPHIES .......................................................... 20 Phoenix “Follows the water” responding directly to the recently published data from Dr. William Boynton, PI (and 1. INTRODUCTION Phoenix co-I) of the Mars Odyssey Gamma Ray Spectrometer (GRS). GRS data indicate extremely large The first of a new series of highly ambitious missions to quantities of water ice (up to 50% by mass) within the upper explore Mars, Phoenix was selected in August 2003 to 50 cm of the northern polar regolith.
    [Show full text]
  • January 2020 Musical Notes
    Musical Notes January, 2020 Symphony League Preview Mahler’s Symphony no. 5 begins with the most famous four notes since Beethoven’s 5th, includes his greatest love song, the Adagietto, and charts the course from inner agony to ecstasy of the soul. Remember, there is a Free Open Rehearsal Maestro Daniel Stewart at the Civic Auditorium, always brings fresh insights and information Friday, Jan. 31, 7:30 - 10:00. about the music chosen for the concert. This face-to-face encounter is only available at the To listen to Symphony #5 check this League’s Preview. link: https://www.youtube.com/ watch?v=E9D1svZ9Y0s In case you want to invite a friend to the concert you can get more tickets at this Join us at the link: California Grill https://santacruzsymphony.org/how-to- 40 Penny Lane order (off Green Valley) Watsonville Deadline for Preview reservations is Lunch on Friday, January 31, 11:30 a.m. Sat., Jan. 25 To pay by check, please make it out to Santa A hot buffet luncheon Cruz Symphony League, and mail to Cheryl Hammond, 1505 42nd Avenue #30, Capitola, and no host bar. CA 95010. Questions? Call Cheryl $35 for League Members, at 831-475-9482. $40 for non-Members Check this link to make your reservation: https://www.santacruzsymphonyleague.org/ Reservations required by Sat., Jan. 25 reservations/concert-preview-catharsis Calling all WW II buffs and Rosie the Riveters! Grab your fedora and your seamed stockings and join the Symphony League’s Wings of Glory 1940s Ball at the historic and newly renovated Vets Hall 846 Front Street in downtown Santa Cruz.
    [Show full text]
  • Download Preprint
    This is a non-peer-reviewed preprint submitted to EarthArXiv Global inventories of inverted stream channels on Earth and Mars Abdallah S. Zakia*, Colin F. Painb, Kenneth S. Edgettc, Sébastien Castelltorta a Department of Earth Sciences, University of Geneva, Rue des Maraîchers 13, 1205 Geneva, Switzerland. b MED_Soil, Departamento de Cristlografía, Mineralogía y Quimica Agrícola, Universidad de Sevilla, Calle Profesor García González s/n, 41012 Sevilla, Spain. c Malin Space Science Systems, Inc., P.O. Box 910148, San Diego, CA 92191, USA Corresponding Author: a* Department of Earth Sciences, University of Geneva, Rue des Maraîchers 13, 1205 Geneva, Switzerland. ([email protected]) ABSTRACT Data from orbiting and landed spacecraft have provided vast amounts of information regarding fluvial and fluvial-related landforms and sediments on Mars. One variant of these landforms are sinuous ridges that have been interpreted to be remnant evidence for ancient fluvial activity, observed at hundreds of martian locales. In order to further understanding of these martian landforms, this paper inventories the 107 known and unknown inverted channel sites on Earth; these offer 114 different examples that consist of materials ranging in age from Upper Ordovician to late Holocene. These examples record several climatic events from the Upper Ordovician glaciation to late Quaternary climate oscillation. These Earth examples include inverted channels in deltaic and alluvial fan sediment, providing new analogs to their martian counterparts. This global
    [Show full text]
  • Climatic Implications of New Global Mapping of Near-Surface Water-Equivalent Hydrogen on Mars Asmin V. Pathar
    Driven by Excess? Climatic Implications of New Global Mapping of Near-Surface Water-Equivalent Hydrogen on Mars Asmin V. Pathare1, William C. Feldman1, Thomas H. Prettyman1, Sylvestre Maurice2 1Planetary Science Institute, Tucson, AZ 91106; 2Institut de Recherche en Astrophysique et Planétologie, Université Paul Sabatier, Toulouse, France. Editorial correspondence to: Asmin Pathare Planetary Science Institute 1700 E. Fort Lowell, Suite 106 Tucson, AZ 85719 Email: [email protected] Abstract We present improved Mars Odyssey Neutron Spectrometer (MONS) maps of near-surface Water-Equivalent Hydrogen (WEH) on Mars that have intriguing implications for the global distribution of “excess” ice, which occurs when the mass fraction of water ice exceeds the threshold amount needed to saturate the pore volume in normal soils. We have refined the crossover technique of Feldman et al. (2011) by using spatial deconvolution and Gaussian weighting to create the first globally self-consistent map of WEH. At low latitudes, our new maps indicate that WEH exceeds 15% in several near-equatorial regions, such as Arabia Terra, which has important implications for the types of hydrated minerals present at low latitudes. At high latitudes, we demonstrate that the disparate MONS and Phoenix Robotic Arm (RA) observations of near surface WEH can be reconciled by a three-layer model incorporating dry soil over fully saturated pore ice over pure excess ice: such a three-layer model can also potentially explain the strong anticorrelation of subsurface ice content and ice table depth observed at high latitudes. At moderate latitudes, we show that the distribution of recently formed impact craters is also consistent with our latest MONS results, as both the shallowest ice- exposing crater and deepest non-ice-exposing crater at each impact site are in good agreement with our predictions of near-surface WEH.
    [Show full text]
  • Full Day Activity Options
    FULL DAY ACTIVITY OPTIONS LAKE TAHOE observation platform, located at 9,123 feet. Take in views of the Carson Valley, Desolation Wilderness and shore-to- shore views of Lake Tahoe from the Skyway Canopy Zip Mark Twain wrote that Lake Tahoe is “the fairest picture Tour, aerial bridges and the Gondola June through Sep- Lthe whole earth affords.” If you’re spending more than a tember. day or two in the Reno Tahoe area, you do not want to let skiheavenly.com, 775-586-7000 this opportunity pass you by. Just a 40-minute drive from - A ride on the scenic Aerial Tram is a spec- the Reno-Tahoe International Airport, North Lake Tahoe of- Squaw Valley tacular and leisurely ride 2,000 vertical feet to High Camp, fers a multitude of attractions no matter what the season. el. 8200’. The Aerial Tram is one of Squaw Valley’s most The drive around Lake Tahoe is 72 miles, one of the most popular year-round attractions. Once you reach the top, scenic drives in America. enjoy panoramic views of Lake Tahoe as well as access to numerous activities, including a mountaintop pool, roller Blessed with sparkling natural beauty, Lake Tahoe has skating, hiking and dining through September. been selected by USA TODAY readers as the #1 lake in the United States. The lake is known for the clarity of its water squawalpine.com, 800-403-0206 and the panorama of surrounding mountains on all sides. At 6,229 feet above sea level, Lake Tahoe is the highest Carriage & Sleigh Rides - In the lake of its size in the United States, measuring 22 miles Borges Family Carriage Sleigh and Pony Rides spring, summer and autumn, the carriage rides travel long by 12 miles wide, with a surface area of 191 square through a peaceful neighborhood to a sandy beach along miles and an average depth of 989 feet and 72 miles of Lake Tahoe.
    [Show full text]