Effects of Rock Avalanches on Glacier Behaviour and Moraine Formation
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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. -
Basal Control of Supraglacial Meltwater Catchments on the Greenland Ice Sheet
The Cryosphere, 12, 3383–3407, 2018 https://doi.org/10.5194/tc-12-3383-2018 © Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. Basal control of supraglacial meltwater catchments on the Greenland Ice Sheet Josh Crozier1, Leif Karlstrom1, and Kang Yang2,3 1University of Oregon Department of Earth Sciences, Eugene, Oregon, USA 2School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China 3Joint Center for Global Change Studies, Beijing 100875, China Correspondence: Josh Crozier ([email protected]) Received: 5 April 2018 – Discussion started: 17 May 2018 Revised: 13 October 2018 – Accepted: 15 October 2018 – Published: 29 October 2018 Abstract. Ice surface topography controls the routing of sur- sliding regimes. Predicted changes to subglacial hydraulic face meltwater generated in the ablation zones of glaciers and flow pathways directly caused by changing ice surface to- ice sheets. Meltwater routing is a direct source of ice mass pography are subtle, but temporal changes in basal sliding or loss as well as a primary influence on subglacial hydrology ice thickness have potentially significant influences on IDC and basal sliding of the ice sheet. Although the processes spatial distribution. We suggest that changes to IDC size and that determine ice sheet topography at the largest scales are number density could affect subglacial hydrology primarily known, controls on the topographic features that influence by dispersing the englacial–subglacial input of surface melt- meltwater routing at supraglacial internally drained catch- water. ment (IDC) scales ( < 10s of km) are less well constrained. Here we examine the effects of two processes on ice sheet surface topography: transfer of bed topography to the surface of flowing ice and thermal–fluvial erosion by supraglacial 1 Introduction meltwater streams. -
Introduction to Geological Process in Illinois Glacial
INTRODUCTION TO GEOLOGICAL PROCESS IN ILLINOIS GLACIAL PROCESSES AND LANDSCAPES GLACIERS A glacier is a flowing mass of ice. This simple definition covers many possibilities. Glaciers are large, but they can range in size from continent covering (like that occupying Antarctica) to barely covering the head of a mountain valley (like those found in the Grand Tetons and Glacier National Park). No glaciers are found in Illinois; however, they had a profound effect shaping our landscape. More on glaciers: http://www.physicalgeography.net/fundamentals/10ad.html Formation and Movement of Glacial Ice When placed under the appropriate conditions of pressure and temperature, ice will flow. In a glacier, this occurs when the ice is at least 20-50 meters (60 to 150 feet) thick. The buildup results from the accumulation of snow over the course of many years and requires that at least some of each winter’s snowfall does not melt over the following summer. The portion of the glacier where there is a net accumulation of ice and snow from year to year is called the zone of accumulation. The normal rate of glacial movement is a few feet per day, although some glaciers can surge at tens of feet per day. The ice moves by flowing and basal slip. Flow occurs through “plastic deformation” in which the solid ice deforms without melting or breaking. Plastic deformation is much like the slow flow of Silly Putty and can only occur when the ice is under pressure from above. The accumulation of meltwater underneath the glacier can act as a lubricant which allows the ice to slide on its base. -
Harmony Ridge-Lucania's Southeast Ridge
Harmony Ridge-Lucania’s Southeast Ridge S t e v e n G a s k il l , Colorado Mountain Club T h E complex massif of Mount Lu- cania rises to 17,147 feet in the St. Elias Mountains, only 50 miles north of Mount Logan. Before we started, no route had yet been completed on its southeast face for obvious reasons. The ridges are all long and draped with hanging glaciers; the faces are forbidding and well fortified. Of the myriad of ridges which make up this side of the mountain, only one goes directly to the summit, the southeast ridge, rising above a tor tured icefall in a perfect line toward the top. This was our objective. Phil Raevsky, Mike Ruckhaus, my brother Craig* and I landed on the upper Dennis Glacier on April 23, a perfect day which allowed us an unsurpassed view of the complex of St. Elias peaks, pinnacles and glaciers and especially of our entire route and planned traverse. We contemplated an alpine-style climb over Mount Lucania, across Mount Steele and finally down Steele’s beautiful east ridge, followed by a 70-mile hike out to the Alaska Highway. The mountain of equipment and food needed for the climb would make us ferry loads, at least up to the summit. By then we hoped to have reduced it to a load apiece. We spent the first day carrying two loads each up the two-and-a-half miles to our first camp, Echo Flats, at the base of the icefall. The worst dangers of the climb start there. -
Glacier (And Ice Sheet) Mass Balance
Glacier (and ice sheet) Mass Balance The long-term average position of the highest (late summer) firn line ! is termed the Equilibrium Line Altitude (ELA) Firn is old snow How an ice sheet works (roughly): Accumulation zone ablation zone ice land ocean • Net accumulation creates surface slope Why is the NH insolation important for global ice• sheetSurface advance slope causes (Milankovitch ice to flow towards theory)? edges • Accumulation (and mass flow) is balanced by ablation and/or calving Why focus on summertime? Ice sheets are very sensitive to Normal summertime temperatures! • Ice sheet has parabolic shape. • line represents melt zone • small warming increases melt zone (horizontal area) a lot because of shape! Slightly warmer Influence of shape Warmer climate freezing line Normal freezing line ground Furthermore temperature has a powerful influence on melting rate Temperature and Ice Mass Balance Summer Temperature main factor determining ice growth e.g., a warming will Expand ablation area, lengthen melt season, increase the melt rate, and increase proportion of precip falling as rain It may also bring more precip to the region Since ablation rate increases rapidly with increasing temperature – Summer melting controls ice sheet fate* – Orbital timescales - Summer insolation must control ice sheet growth *Not true for Antarctica in near term though, where it ʼs too cold to melt much at surface Temperature and Ice Mass Balance Rule of thumb is that 1C warming causes an additional 1m of melt (see slope of ablation curve at right) -
Landtype Associations (Ltas) of the Northern Highland Scale: 1:650,000 Wisconsin Transverse Mercator NAD83(91) Map NH3 - Ams
Landtype Associations (LTAs) of the Northern Highland Scale: 1:650,000 Wisconsin Transverse Mercator NAD83(91) Map NH3 - ams 212Xb03 212Xb03 212Xb04 212Xb05 212Xb06 212Xb01 212Xb02 212Xb02 212Xb01 212Xb03 212Xb05 212Xb03 212Xb02 212Xb 212Xb07 212Xb07 212Xb01 212Xb03 212Xb05 212Xb07 212Xb08 212Xb03 212Xb07 212Xb07 212Xb01 212Xb01 212Xb07 Landtype Associations 212Xb01 212Xb01 212Xb02 212Xb03 212Xb04 212Xb05 This map is based on the National Hierarchical Framework of Ecological Units 212Xb06 (NHFEU) (Cleland et al. 1997). 212Xb07 The ecological landscapes used in this handbook are based substantially on 212Xb08 Subsections of the NHFEU. Ecological landscapes use the same boundaries as NHFEU Sections or Subsections. However, some NHFEU Subsections were combined to reduce the number of geographical units in the state to a manageable Ecological Landscape number. LTA descriptions can be found on the back page of this map. County Boundaries 0 2.75 5.5 11 16.5 22 Miles Sections Kilometers Subsections 0 4 8 16 24 32 Ecological Landscapes of Wisconsin Handbook - 1805.1 WDNR, 2011 Landtype Association Descriptions for the Northern Highland Ecological Landscape 212Xb01 Northern Highland Outwash The characteristic landform pattern is undulating pitted and unpitted Plains outwash plain with swamps, bogs, and lakes common. Soils are predominantly well drained sandy loam over outwash. Common habitat types include forested lowland, ATM, TMC, PArVAa and AVVb. 212Xb02 Vilas-Oneida Sandy Hills The characteristic landform pattern is rolling collapsed outwash plain with bogs common. Soils are predominantly excessively drained loamy sand over outwash or acid loamy sand debris flow. Common habitat types include PArVAa, ArQV, forested lowland, AVVb and TMC. 212Xb03 Vilas-Oneida Outwash Plains The characteristic landform pattern is nearly level pitted and unpitted outwash plain with bogs and lakes common. -
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. -
North American Notes
268 NORTH AMERICAN NOTES NORTH AMERICAN NOTES BY KENNETH A. HENDERSON HE year I 967 marked the Centennial celebration of the purchase of Alaska from Russia by the United States and the Centenary of the Articles of Confederation which formed the Canadian provinces into the Dominion of Canada. Thus both Alaska and Canada were in a mood to celebrate, and a part of this celebration was expressed · in an extremely active climbing season both in Alaska and the Yukon, where some of the highest mountains on the continent are located. While much of the officially sponsored mountaineering activity was concentrated in the border mountains between Alaska and the Yukon, there was intense activity all over Alaska as well. More information is now available on the first winter ascent of Mount McKinley mentioned in A.J. 72. 329. The team of eight was inter national in scope, a Frenchman, Swiss, German, Japanese, and New Zealander, the rest Americans. The successful group of three reached the summit on February 28 in typical Alaskan weather, -62° F. and winds of 35-40 knots. On their return they were stormbound at Denali Pass camp, I7,3oo ft. for seven days. For the forty days they were on the mountain temperatures averaged -35° to -40° F. (A.A.J. I6. 2I.) One of the most important attacks on McKinley in the summer of I967 was probably the three-pronged assault on the South face by the three parties under the general direction of Boyd Everett (A.A.J. I6. IO). The fourteen men flew in to the South east fork of the Kahiltna glacier on June 22 and split into three groups for the climbs. -
Forecasting Temperate Alpine Glacier Survival from Accumulation Zone Observations
The Cryosphere, 4, 67–75, 2010 www.the-cryosphere.net/4/67/2010/ The Cryosphere © Author(s) 2010. This work is distributed under the Creative Commons Attribution 3.0 License. Forecasting temperate alpine glacier survival from accumulation zone observations M. S. Pelto Environmental Sciences, Nichols College, Dudley, MA 01571, USA Received: 16 April 2009 – Published in The Cryosphere Discuss.: 19 May 2009 Revised: 18 December 2009 – Accepted: 19 January 2010 – Published: 29 January 2010 Abstract. Temperate alpine glacier survival is dependent on change (WGMS, 2008). The worldwide retreat of moun- the consistent presence of an accumulation zone. Frequent tain glaciers is one of the clearest signals of ongoing climate low accumulation area ratio values, below 30%, indicate the change (Haeberli and Hoelzel, 1995; Oerlemans, 1994). The lack of a consistent accumulation zone, which leads to sub- retreat is a reflection of strongly negative mass balances over stantial thinning of the glacier in the accumulation zone. This the last 30 years (WGMS, 2007). In some cases the negative thinning is often evident from substantial marginal recession, balances have led to the loss of a glacier (Pelto, 2006; Knoll emergence of new rock outcrops and surface elevation de- and Kerschner, 2009). cline in the accumulation zone. In the North Cascades 9 of Terminus change observations identify the response of the the 12 examined glaciers exhibit characteristics of substantial glacier to recent climate changes; however, terminus change accumulation zone thinning; marginal recession or emergent does not identify the ability of a glacier to survive. A glacier bedrock areas in the accumulation zone. The longitudinal can retreat rapidly and still reestablish equilibrium. -
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. -
The Dynamics and Mass Budget of Aretic Glaciers
DA NM ARKS OG GRØN L ANDS GEO L OG I SKE UNDERSØGELSE RAP P ORT 2013/3 The Dynamics and Mass Budget of Aretic Glaciers Abstracts, IASC Network of Aretic Glaciology, 9 - 12 January 2012, Zieleniec (Poland) A. P. Ahlstrøm, C. Tijm-Reijmer & M. Sharp (eds) • GEOLOGICAL SURVEY OF D EN MARK AND GREENLAND DANISH MINISTAV OF CLIMATE, ENEAGY AND BUILDING ~ G E U S DANMARKS OG GRØNLANDS GEOLOGISKE UNDERSØGELSE RAPPORT 201 3 / 3 The Dynamics and Mass Budget of Arctic Glaciers Abstracts, IASC Network of Arctic Glaciology, 9 - 12 January 2012, Zieleniec (Poland) A. P. Ahlstrøm, C. Tijm-Reijmer & M. Sharp (eds) GEOLOGICAL SURVEY OF DENMARK AND GREENLAND DANISH MINISTRY OF CLIMATE, ENERGY AND BUILDING Indhold Preface 5 Programme 6 List of participants 11 Minutes from a special session on tidewater glaciers research in the Arctic 14 Abstracts 17 Seasonal and multi-year fluctuations of tidewater glaciers cliffson Southern Spitsbergen 18 Recent changes in elevation across the Devon Ice Cap, Canada 19 Estimation of iceberg to the Hansbukta (Southern Spitsbergen) based on time-lapse photos 20 Seasonal and interannual velocity variations of two outlet glaciers of Austfonna, Svalbard, inferred by continuous GPS measurements 21 Discharge from the Werenskiold Glacier catchment based upon measurements and surface ablation in summer 2011 22 The mass balance of Austfonna Ice Cap, 2004-2010 23 Overview on radon measurements in glacier meltwater 24 Permafrost distribution in coastal zone in Hornsund (Southern Spitsbergen) 25 Glacial environment of De Long Archipelago