Flow and Structure in a Dendritic Glacier with Bedrock Steps
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
University Microfilms, Inc., Ann Arbor, Michigan GEOLOGY of the SCOTT GLACIER and WISCONSIN RANGE AREAS, CENTRAL TRANSANTARCTIC MOUNTAINS, ANTARCTICA
This dissertation has been /»OOAOO m icrofilm ed exactly as received MINSHEW, Jr., Velon Haywood, 1939- GEOLOGY OF THE SCOTT GLACIER AND WISCONSIN RANGE AREAS, CENTRAL TRANSANTARCTIC MOUNTAINS, ANTARCTICA. The Ohio State University, Ph.D., 1967 Geology University Microfilms, Inc., Ann Arbor, Michigan GEOLOGY OF THE SCOTT GLACIER AND WISCONSIN RANGE AREAS, CENTRAL TRANSANTARCTIC MOUNTAINS, ANTARCTICA DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University by Velon Haywood Minshew, Jr. B.S., M.S, The Ohio State University 1967 Approved by -Adviser Department of Geology ACKNOWLEDGMENTS This report covers two field seasons in the central Trans- antarctic Mountains, During this time, the Mt, Weaver field party consisted of: George Doumani, leader and paleontologist; Larry Lackey, field assistant; Courtney Skinner, field assistant. The Wisconsin Range party was composed of: Gunter Faure, leader and geochronologist; John Mercer, glacial geologist; John Murtaugh, igneous petrclogist; James Teller, field assistant; Courtney Skinner, field assistant; Harry Gair, visiting strati- grapher. The author served as a stratigrapher with both expedi tions . Various members of the staff of the Department of Geology, The Ohio State University, as well as some specialists from the outside were consulted in the laboratory studies for the pre paration of this report. Dr. George E. Moore supervised the petrographic work and critically reviewed the manuscript. Dr. J. M. Schopf examined the coal and plant fossils, and provided information concerning their age and environmental significance. Drs. Richard P. Goldthwait and Colin B. B. Bull spent time with the author discussing the late Paleozoic glacial deposits, and reviewed portions of the manuscript. -
NORSK GEOLOGISK TIDSSKRIFT 45 by IVAR KLOVNING and ULF
NORSK GEOLOGISK TIDSSKRIFT 45 AN EARLY POST-GLACIAL POLLEN PROFILE FROM FLÅMSDALEN, A TRIBUTARY VALLEY TO THE SOGNEFJORD, WESTERN NORWAY BY IVAR KLOVNING and ULF HAFSTEN (University Botanical Museum, Bergen) Abstract. Pollen analysis and radiocarbon measurements of nekron-mud from the base of a 5 m deep organic deposit in a pot-hole on Furuberget, a rocky promontory in the lower part of the Flåmsdalen valley, show that this part of the valley was free of ice befare 7000 B.C. Introduction Flåmsdalen, a 20 km long, much glaciated tributary valley to the Sognefjord, cutting southwards into the peripheral parts of the Har dangervidda plateau, contains a number of erosional features from the time the ice retreated from this valley (H. HoLTEDAHL 1960). Among these is a series of sharply incised, mostly very narrow canyons of different sizes and shapes, often fringed with pot-hoies. The canyons form a system, with a major canyon, present in parts of the main valley, forming the river channel of the present river and a series of tributary canyons which are mostly dry at the present time. These tributary canyons, which are supposed to be sub-glacial erosional phenomena, are very numerous on and around Furuberget, a broad and steep, rocky promontory (riegel), nearly 200m high, that almost doses the Flåmsdalen valley 5 km south of the head of the Aurland fjord (Fig. 1). The fact that the river here, at this typical valley step, has cut a deep canyon, indicates that the valley once was com pletely closed at this place. The most extensive canyon occurring on Furuberget runs in an are from southwest to east across the central part of the promontory and contains a series of pot-hales that are, especially in the flat, eastern part of the canyon, completely filled with organic matter (KLOVNING 1963). -
Jökulhlaups in Skaftá: a Study of a Jökul- Hlaup from the Western Skaftá Cauldron in the Vatnajökull Ice Cap, Iceland
Jökulhlaups in Skaftá: A study of a jökul- hlaup from the Western Skaftá cauldron in the Vatnajökull ice cap, Iceland Bergur Einarsson, Veðurstofu Íslands Skýrsla VÍ 2009-006 Jökulhlaups in Skaftá: A study of jökul- hlaup from the Western Skaftá cauldron in the Vatnajökull ice cap, Iceland Bergur Einarsson Skýrsla Veðurstofa Íslands +354 522 60 00 VÍ 2009-006 Bústaðavegur 9 +354 522 60 06 ISSN 1670-8261 150 Reykjavík [email protected] Abstract Fast-rising jökulhlaups from the geothermal subglacial lakes below the Skaftá caul- drons in Vatnajökull emerge in the Skaftá river approximately every year with 45 jökulhlaups recorded since 1955. The accumulated volume of flood water was used to estimate the average rate of water accumulation in the subglacial lakes during the last decade as 6 Gl (6·106 m3) per month for the lake below the western cauldron and 9 Gl per month for the eastern caul- dron. Data on water accumulation and lake water composition in the western cauldron were used to estimate the power of the underlying geothermal area as ∼550 MW. For a jökulhlaup from the Western Skaftá cauldron in September 2006, the low- ering of the ice cover overlying the subglacial lake, the discharge in Skaftá and the temperature of the flood water close to the glacier margin were measured. The dis- charge from the subglacial lake during the jökulhlaup was calculated using a hypso- metric curve for the subglacial lake, estimated from the form of the surface cauldron after jökulhlaups. The maximum outflow from the lake during the jökulhlaup is esti- mated as 123 m3 s−1 while the maximum discharge of jökulhlaup water at the glacier terminus is estimated as 97 m3 s−1. -
Project ICEFLOW
ICEFLOW: short-term movements in the Cryosphere Bas Altena Department of Geosciences, University of Oslo. now at: Institute for Marine and Atmospheric research, Utrecht University. Bas Altena, project Iceflow geometric properties from optical remote sensing Bas Altena, project Iceflow Sentinel-2 Fast flow through icefall [published] Ensemble matching of repeat satellite images applied to measure fast-changing ice flow, verified with mountain climber trajectories on Khumbu icefall, Mount Everest. Journal of Glaciology. [outreach] see also ESA Sentinel Online: Copernicus Sentinel-2 monitors glacier icefall, helping climbers ascend Mount Everest Bas Altena, project Iceflow Sentinel-2 Fast flow through icefall 0 1 2 km glacier surface speed [meter/day] Khumbu Glacier 0.2 0.4 0.6 0.8 1.0 1.2 Mt. Everest 300 1800 1200 600 0 2/4 right 0 5/4 4/4 left 4/4 2/4 R 3/4 L -300 terrain slope [deg] Nuptse surface velocity contours Western Chm interval per 1/4 [meter/day] 10◦ 20◦ 30◦ 40◦ [outreach] see also Adventure Mountain: Mount Everest: The way the Khumbu Icefall flows Bas Altena, project Iceflow Sentinel-2 Fast flow through icefall ∆H Ut=2000 U t=2020 H internal velocity profile icefall α 2A @H 3 U = − 3+2 H tan αρgH @x MSc thesis research at Wageningen University Bas Altena, project Iceflow Quantifying precision in velocity products 557 200 557 600 7 666 200 NCC 7 666 000 score 1 7 665 800 Θ 0.5 0 7 665 600 557 460 557 480 557 500 557 520 7 665 800 search space zoom in template/chip correlation surface 7 666 200 7 666 200 7 666 000 7 666 000 7 665 800 7 665 800 7 665 600 7 665 600 557 200 557 600 557 200 557 600 [submitted] Dispersion estimation of remotely sensed glacier displacements for better error propagation. -
List of Place-Names in Antarctica Introduced by Poland in 1978-1990
POLISH POLAR RESEARCH 13 3-4 273-302 1992 List of place-names in Antarctica introduced by Poland in 1978-1990 The place-names listed here in alphabetical order, have been introduced to the areas of King George Island and parts of Nelson Island (West Antarctica), and the surroundings of A. B. Dobrowolski Station at Bunger Hills (East Antarctica) as the result of Polish activities in these regions during the period of 1977-1990. The place-names connected with the activities of the Polish H. Arctowski Station have been* published by Birkenmajer (1980, 1984) and Tokarski (1981). Some of them were used on the Polish maps: 1:50,000 Admiralty Bay and 1:5,000 Lions Rump. The sheet reference is to the maps 1:200,000 scale, British Antarctic Territory, South Shetland Islands, published in 1968: King George Island (sheet W 62 58) and Bridgeman Island (Sheet W 62 56). The place-names connected with the activities of the Polish A. B. Dobrowolski Station have been published by Battke (1985) and used on the map 1:5,000 Antarctic Territory — Bunger Oasis. Agat Point. 6211'30" S, 58'26" W (King George Island) Small basaltic promontory with numerous agates (hence the name), immediately north of Staszek Cove. Admiralty Bay. Sheet W 62 58. Polish name: Przylądek Agat (Birkenmajer, 1980) Ambona. 62"09'30" S, 58°29' W (King George Island) Small rock ledge, 85 m a. s. 1. {ambona, Pol. = pulpit), above Arctowski Station, Admiralty Bay, Sheet W 62 58 (Birkenmajer, 1980). Andrzej Ridge. 62"02' S, 58° 13' W (King George Island) Ridge in Rose Peak massif, Arctowski Mountains. -
Analysis of Groundwater Flow Beneath Ice Sheets
SE0100146 Technical Report TR-01-06 Analysis of groundwater flow beneath ice sheets Boulton G S, Zatsepin S, Maillot B University of Edinburgh Department of Geology and Geophysics March 2001 Svensk Karnbranslehantering AB Swedish Nuclear Fuel and Waste Management Co Box 5864 SE-102 40 Stockholm Sweden Tel 08-459 84 00 +46 8 459 84 00 Fax 08-661 57 19 +46 8 661 57 19 32/ 23 PLEASE BE AWARE THAT ALL OF THE MISSING PAGES IN THIS DOCUMENT WERE ORIGINALLY BLANK Analysis of groundwater flow beneath ice sheets Boulton G S, Zatsepin S, Maillot B University of Edinburgh Department of Geology and Geophysics March 2001 This report concerns a study which was conducted for SKB. The conclusions and viewpoints presented in the report are those of the authors and do not necessarily coincide with those of the client. Summary The large-scale pattern of subglacial groundwater flow beneath European ice sheets was analysed in a previous report /Boulton and others, 1999/. It was based on a two- dimensional flowline model. In this report, the analysis is extended to three dimensions by exploring the interactions between groundwater and tunnel flow. A theory is develop- ed which suggests that the large-scale geometry of the hydraulic system beneath an ice sheet is a coupled, self-organising system. In this system the pressure distribution along tunnels is a function of discharge derived from basal meltwater delivered to tunnels by groundwater flow, and the pressure along tunnels itself sets the base pressure which determines the geometry of catchments and flow towards the tunnel. -
P1616 Text-Only PDF File
A Geologic Guide to Wrangell–Saint Elias National Park and Preserve, Alaska A Tectonic Collage of Northbound Terranes By Gary R. Winkler1 With contributions by Edward M. MacKevett, Jr.,2 George Plafker,3 Donald H. Richter,4 Danny S. Rosenkrans,5 and Henry R. Schmoll1 Introduction region—his explorations of Malaspina Glacier and Mt. St. Elias—characterized the vast mountains and glaciers whose realms he invaded with a sense of astonishment. His descrip Wrangell–Saint Elias National Park and Preserve (fig. tions are filled with superlatives. In the ensuing 100+ years, 6), the largest unit in the U.S. National Park System, earth scientists have learned much more about the geologic encompasses nearly 13.2 million acres of geological won evolution of the parklands, but the possibility of astonishment derments. Furthermore, its geologic makeup is shared with still is with us as we unravel the results of continuing tectonic contiguous Tetlin National Wildlife Refuge in Alaska, Kluane processes along the south-central Alaska continental margin. National Park and Game Sanctuary in the Yukon Territory, the Russell’s superlatives are justified: Wrangell–Saint Elias Alsek-Tatshenshini Provincial Park in British Columbia, the is, indeed, an awesome collage of geologic terranes. Most Cordova district of Chugach National Forest and the Yakutat wonderful has been the continuing discovery that the disparate district of Tongass National Forest, and Glacier Bay National terranes are, like us, invaders of a sort with unique trajectories Park and Preserve at the north end of Alaska’s panhan and timelines marking their northward journeys to arrive in dle—shared landscapes of awesome dimensions and classic today’s parklands. -
Glacial Cirques As Palaeoenvironmental Indicators: Their Potential and Limitations
Glacial cirques as palaeoenvironmental indicators: their potential and limitations Barr, I. D., & Spagnolo, M. (2015). Glacial cirques as palaeoenvironmental indicators: their potential and limitations. Earth-Science Reviews, 151, 48-78. https://doi.org/10.1016/j.earscirev.2015.10.004 Published in: Earth-Science Reviews Document Version: Peer reviewed version Queen's University Belfast - Research Portal: Link to publication record in Queen's University Belfast Research Portal Publisher rights ©2015 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc- nd/4.0/ which permits distribution and reproduction for non-commercial purposes, provided the author and source are cited. General rights Copyright for the publications made accessible via the Queen's University Belfast Research Portal is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy The Research Portal is Queen's institutional repository that provides access to Queen's research output. Every effort has been made to ensure that content in the Research Portal does not infringe any person's rights, or applicable UK laws. If you discover content in the Research Portal that you believe breaches copyright or violates any law, please contact [email protected]. Download date:24. Sep. 2021 Glacial cirques as palaeoenvironmental indicators: their potential and limitations Iestyn D. Barr (Corresponding author) School of Geography, Archaeology and Palaeoecology, Queen’s University Belfast, BT7 1NN, Belfast, UK Email: [email protected] Tel: +44 (0)28 9097 5146 Matteo Spagnolo School of Geosciences, University of Aberdeen, Elphinstone Road, AB243UF, Aberdeen, UK Abstract Glacial cirques are armchair-shaped erosional hollows, typified by steep headwalls and, often, overdeepened floors. -
Ice-Stream Flow Switching by Up-Ice Propagation of Instabilities Along Glacial Marginal Troughs
Ice-stream flow switching by up-ice propagation of instabilities along glacial marginal troughs Etienne Brouard1* & Patrick Lajeunesse1 5 1 Centre d’études nordiques & Département de géographie, Université Laval, Québec, Québec Correspondence to: Etienne Brouard ([email protected]) Abstract. Ice stream networks constitute the arteries of ice sheets through which large volumes of glacial ice are rapidly delivered from the continent to the ocean. Modifications in ice stream networks have a major impact on ice sheets mass balance and global sea level. Reorganizations in the drainage network of ice streams have been reported in both modern and palaeo- 10 ice sheets and usually result in ice streams switching their trajectory and/or shutting down. While some hypotheses for the reorganization of ice streams have been proposed, the mechanisms that control the switching of ice streams remain poorly understood and documented. Here, we interpret a flow switch in an ice stream system that occurred prior to the last glaciation on the northeastern Baffin Island shelf (Arctic Canada) through glacial erosion of a marginal trough, i.e., deep parallel-to-coast bedrock moats located up-ice of a cross-shelf trough. Shelf geomorphology imaged by high-resolution swath bathymetry and 15 seismostratigraphic data in the area indicate the extension of ice streams from Scott and Hecla & Griper troughs towards the interior of the Laurentide Ice Sheet. Up-ice propagation of ice streams through a marginal trough is interpreted to have led to the piracy of the neighboring ice catchment that in turn induced an adjacent ice stream flow switch and shutdown. -
Of the Tasman Glacier
1 ICE DYNAMICS OF THE HAUPAPA/TASMAN GLACIER MEASURED AT HIGH SPATIAL AND TEMPORAL RESOLUTION, AORAKI/MOUNT COOK, NEW ZEALAND A THESIS Presented to the School of Geography, Environment and Earth Sciences Victoria University of Wellington In Partial Fulfilment of the Requirements for the Degree of MASTERS OF SCIENCE By Edmond Anderson Lui, B.Sc., GradDipEnvLaw Wellington, New Zealand October, 2016 2 TABLE OF CONTENTS SIGNATURE PAGE .................................................................................................................... TITLE PAGE ............................................................................................................................................... 1 TABLE OF CONTENTS .......................................................................................................................... 2 LIST OF FIGURES ..................................................................................................................................... 5 LIST OF TABLES ....................................................................................................................................... 9 LIST OF EQUATIONS ...........................................................................................................................10 ACKNOWLEDGEMENTS ....................................................................................................................11 MOTIVATIONS ........................................................................................................................................12 -
Glacier Mass Balance Bulletin No. 11 (2008–2009)
GLACIER MASS BALANCE BULLETIN Bulletin No. 11 (2008–2009) A contribution to the Global Terrestrial Network for Glaciers (GTN-G) as part of the Global Terrestrial/Climate Observing System (GTOS/GCOS), the Division of Early Warning and Assessment and the Global Environment Outlook as part of the United Nations Environment Programme (DEWA and GEO, UNEP) and the International Hydrological Programme (IHP, UNESCO) Compiled by the World Glacier Monitoring Service (WGMS) ICSU (WDS) – IUGG (IACS) – UNEP – UNESCO – WMO 2011 GLACIER MASS BALANCE BULLETIN Bulletin No. 11 (2008–2009) A contribution to the Global Terrestrial Network for Glaciers (GTN-G) as part of the Global Terrestrial/Climate Observing System (GTOS/GCOS), the Division of Early Warning and Assessment and the Global Environment Outlook as part of the United Nations Environment Programme (DEWA and GEO, UNEP) and the International Hydrological Programme (IHP, UNESCO) Compiled by the World Glacier Monitoring Service (WGMS) Edited by Michael Zemp, Samuel U. Nussbaumer, Isabelle Gärtner-Roer, Martin Hoelzle, Frank Paul, Wilfried Haeberli World Glacier Monitoring Service Department of Geography University of Zurich Switzerland ICSU (WDS) – IUGG (IACS) – UNEP – UNESCO – WMO 2011 Imprint World Glacier Monitoring Service c/o Department of Geography University of Zurich Winterthurerstrasse 190 CH-8057 Zurich Switzerland http://www.wgms.ch [email protected] Editorial Board Michael Zemp Department of Geography, University of Zurich Samuel U. Nussbaumer Department of Geography, University of Zurich -
1 Andrews Glacier in August 2016 Tyndall Glacier Lidar Scan in May
Final Report for “Glacier and perennial snowfield mass balance of Rocky Mountain National Park (ROMO): Past, Present, and Future” Task Agreement Number P16AC00826 PI Dr. Daniel McGrath June 28, 2019 Department of Geosciences Colorado State University [email protected] Andrews Glacier in August 2016 Tyndall Glacier LiDAR scan in May 2016 1 Summary of Key Project Outcomes • Over the past ~50 years, geodetic glacier mass balances for four glaciers along the Front Range have been highly variable; for example, Tyndall Glacier thickened slightly, while Arapaho Glacier thinned by >20 m. These glaciers are closely located in space (~30 km) and hence the regional climate forcing is comparable. This variability points to the important role of local topographic/climatological controls (such as wind-blown snow redistribution and topographic shading) on the mass balance of these very small glaciers (~0.1-0.2 km2). • Since 2001, glacier area (for 11 glaciers on the Front Range) has varied ± 40%, with changes most commonly driven by interannual variability in seasonal snow. However, between 2001 and 2017, the glaciers exhibited limited net change in area. Previous work (Hoffman et al., 2007) found that glacier area had started to decline starting in ~2000. • Seasonal mass turnover is very high for Andrews and Tyndall glaciers. On average, the glaciers gain and lose ~9 m of elevation each year. Such extraordinary amounts of snow accumulation is primarily the result of wind-blown snow redistribution into these basins (and to a certain degree, avalanching at Tyndall Glacier) and exceeds observed peak snow water equivalent at a nearby SNOTEL station by 5.5 times.