The High Arctic Geopotential Stress Field and Its Implications for the Geodynamic 2 Evolution
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New Constraints on the Age, Geochemistry
New constraints on the age, geochemistry, and environmental impact of High Arctic Large Igneous Province magmatism: Tracing the extension of the Alpha Ridge onto Ellesmere Island, Canada T.V. Naber1,2, S.E. Grasby1,2, J.P. Cuthbertson2, N. Rayner3, and C. Tegner4,† 1 Geological Survey of Canada–Calgary, Natural Resources Canada, Calgary, Canada 2 Department of Geoscience, University of Calgary, Calgary, Canada 3 Geological Survey of Canada–Northern, Natural Resources Canada, Ottawa, Canada 4 Centre of Earth System Petrology, Department of Geoscience, Aarhus University, Aarhus, Denmark ABSTRACT Island, Nunavut, Canada. In contrast, a new Province (HALIP), is one of the least studied U-Pb age for an alkaline syenite at Audhild of all LIPs due to its remote geographic lo- The High Arctic Large Igneous Province Bay is significantly younger at 79.5 ± 0.5 Ma, cation, and with many exposures underlying (HALIP) represents extensive Cretaceous and correlative to alkaline basalts and rhyo- perennial arctic sea ice. Nevertheless, HALIP magmatism throughout the circum-Arctic lites from other locations of northern Elles- eruptions have been commonly invoked as a borderlands and within the Arctic Ocean mere Island (Audhild Bay, Philips Inlet, and potential driver of major Cretaceous Ocean (e.g., the Alpha-Mendeleev Ridge). Recent Yelverton Bay West; 83–73 Ma). We propose anoxic events (OAEs). Refining the age, geo- aeromagnetic data shows anomalies that ex- these volcanic occurrences be referred to col- chemistry, and nature of these volcanic rocks tend from the Alpha Ridge onto the northern lectively as the Audhild Bay alkaline suite becomes critical then to elucidate how they coast of Ellesmere Island, Nunavut, Canada. -
Data Structure
Data structure – Water The aim of this document is to provide a short and clear description of parameters (data items) that are to be reported in the data collection forms of the Global Monitoring Plan (GMP) data collection campaigns 2013–2014. The data itself should be reported by means of MS Excel sheets as suggested in the document UNEP/POPS/COP.6/INF/31, chapter 2.3, p. 22. Aggregated data can also be reported via on-line forms available in the GMP data warehouse (GMP DWH). Structure of the database and associated code lists are based on following documents, recommendations and expert opinions as adopted by the Stockholm Convention COP6 in 2013: · Guidance on the Global Monitoring Plan for Persistent Organic Pollutants UNEP/POPS/COP.6/INF/31 (version January 2013) · Conclusions of the Meeting of the Global Coordination Group and Regional Organization Groups for the Global Monitoring Plan for POPs, held in Geneva, 10–12 October 2012 · Conclusions of the Meeting of the expert group on data handling under the global monitoring plan for persistent organic pollutants, held in Brno, Czech Republic, 13-15 June 2012 The individual reported data component is inserted as: · free text or number (e.g. Site name, Monitoring programme, Value) · a defined item selected from a particular code list (e.g., Country, Chemical – group, Sampling). All code lists (i.e., allowed values for individual parameters) are enclosed in this document, either in a particular section (e.g., Region, Method) or listed separately in the annexes below (Country, Chemical – group, Parameter) for your reference. -
A Newly Discovered Glacial Trough on the East Siberian Continental Margin
Clim. Past Discuss., doi:10.5194/cp-2017-56, 2017 Manuscript under review for journal Clim. Past Discussion started: 20 April 2017 c Author(s) 2017. CC-BY 3.0 License. De Long Trough: A newly discovered glacial trough on the East Siberian Continental Margin Matt O’Regan1,2, Jan Backman1,2, Natalia Barrientos1,2, Thomas M. Cronin3, Laura Gemery3, Nina 2,4 5 2,6 7 1,2,8 9,10 5 Kirchner , Larry A. Mayer , Johan Nilsson , Riko Noormets , Christof Pearce , Igor Semilietov , Christian Stranne1,2,5, Martin Jakobsson1,2. 1 Department of Geological Sciences, Stockholm University, Stockholm, 106 91, Sweden 2 Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden 10 3 US Geological Survey MS926A, Reston, Virginia, 20192, USA 4 Department of Physical Geography (NG), Stockholm University, SE-106 91 Stockholm, Sweden 5 Center for Coastal and Ocean Mapping, University of New Hampshire, New Hampshire 03824, USA 6 Department of Meteorology, Stockholm University, Stockholm, 106 91, Sweden 7 University Centre in Svalbard (UNIS), P O Box 156, N-9171 Longyearbyen, Svalbard 15 8 Department of Geoscience, Aarhus University, Aarhus, 8000, Denmark 9 Pacific Oceanological Institute, Far Eastern Branch of the Russian Academy of Sciences, 690041 Vladivostok, Russia 10 Tomsk National Research Polytechnic University, Tomsk, Russia Correspondence to: Matt O’Regan ([email protected]) 20 Abstract. Ice sheets extending over parts of the East Siberian continental shelf have been proposed during the last glacial period, and during the larger Pleistocene glaciations. The sparse data available over this sector of the Arctic Ocean has left the timing, extent and even existence of these ice sheets largely unresolved. -
Paleozoic Rocks of Northern Chukotka Peninsula, Russian Far East: Implications for the Tectonicsof the Arctic Region
TECTONICS, VOL. 18, NO. 6, PAGES 977-1003 DECEMBER 1999 Paleozoic rocks of northern Chukotka Peninsula, Russian Far East: Implications for the tectonicsof the Arctic region BorisA. Natal'in,1 Jeffrey M. Amato,2 Jaime Toro, 3,4 and James E. Wright5 Abstract. Paleozoicrocks exposedacross the northernflank of Alaskablock the essentialelement involved in the openingof the the mid-Cretaceousto Late CretaceousKoolen metamorphic Canada basin. domemake up two structurallysuperimposed tectonic units: (1) weaklydeformed Ordovician to Lower Devonianshallow marine 1. Introduction carbonatesof the Chegitununit which formed on a stableshelf and (2) strongly deformed and metamorphosedDevonian to Interestin stratigraphicand tectoniccorrelations between the Lower Carboniferousphyllites, limestones, and an&site tuffs of RussianFar East and Alaska recentlyhas beenrevived as the re- the Tanatapunit. Trace elementgeochemistry, Nd isotopicdata, sult of collaborationbetween North Americanand Russiangeol- and texturalevidence suggest that the Tanataptuffs are differen- ogists.This paperpresents the resultsof one suchstudy from the tiatedcalc-alkaline volcanic rocks possibly derived from a mag- ChegitunRiver valley, Russia,where field work was carriedout matic arc. We interpretthe associatedsedimentary facies as in- to establishthe stratigraphic,structural, and metamorphicrela- dicativeof depositionin a basinal setting,probably a back arc tionshipsin the northernpart of the ChukotkaPeninsula (Figure basin. Orthogneissesin the core of the Koolen dome yielded a -
Re-Evaluation of Strike-Slip Displacements Along and Bordering Nares Strait
Polarforschung 74 (1-3), 129 – 160, 2004 (erschienen 2006) In Search of the Wegener Fault: Re-Evaluation of Strike-Slip Displacements Along and Bordering Nares Strait by J. Christopher Harrison1 Abstract: A total of 28 geological-geophysical markers are identified that lich der Bache Peninsula und Linksseitenverschiebungen am Judge-Daly- relate to the question of strike slip motions along and bordering Nares Strait. Störungssystem (70 km) und schließlich die S-, später SW-gerichtete Eight of the twelve markers, located within the Phanerozoic orogen of Kompression des Sverdrup-Beckens (100 + 35 km). Die spätere Deformation Kennedy Channel – Robeson Channel region, permit between 65 and 75 km wird auf die Rotation (entgegen dem Uhrzeigersinn) und ausweichende West- of sinistral offset on the Judge Daly Fault System (JDFS). In contrast, eight of drift eines semi-rigiden nördlichen Ellesmere-Blocks während der Kollision nine markers located in Kane Basin, Smith Sound and northern Baffin Bay mit der Grönlandplatte zurückgeführt. indicate no lateral displacement at all. Especially convincing is evidence, presented by DAMASKE & OAKEY (2006), that at least one basic dyke of Neoproterozoic age extends across Smith Sound from Inglefield Land to inshore eastern Ellesmere Island without any recognizable strike slip offset. INTRODUCTION These results confirm that no major sinistral fault exists in southern Nares Strait. It is apparent to both earth scientists and the general public To account for the absence of a Wegener Fault in most parts of Nares Strait, that the shape of both coastlines and continental margins of the present paper would locate the late Paleocene-Eocene Greenland plate boundary on an interconnected system of faults that are 1) traced through western Greenland and eastern Arctic Canada provide for a Jones Sound in the south, 2) lie between the Eurekan Orogen and the Precam- satisfactory restoration of the opposing lands. -
Evidence for Slab Material Under Greenland and Links to Cretaceous
PUBLICATIONS Geophysical Research Letters RESEARCH LETTER Evidence for slab material under Greenland 10.1002/2016GL068424 and links to Cretaceous High Key Points: Arctic magmatism • Mid-mantle seismic and gravity anomaly under Greenland identified G. E. Shephard1, R. G. Trønnes1,2, W. Spakman1,3, I. Panet4, and C. Gaina1 • Jurassic-Cretaceous slab linked to paleo-Arctic ocean closure, prior to 1Centre for Earth Evolution and Dynamics (CEED), Department of Geosciences, University of Oslo, Oslo, Norway, 2Natural Amerasia Basin opening 3 • Possible arc-mantle signature in History Museum, University of Oslo, Oslo, Norway, Department of Earth Sciences, Utrecht University, Utrecht, Netherlands, 4 Cretaceous High Arctic LIP volcanism Institut National de l’Information Géographique et Forestière, Laboratoire LAREG, Université Paris Diderot, Paris, France Supporting Information: Abstract Understanding the evolution of extinct ocean basins through time and space demands the • Supporting Information S1 integration of surface kinematics and mantle dynamics. We explore the existence, origin, and implications Correspondence to: of a proposed oceanic slab burial ground under Greenland through a comparison of seismic tomography, G. E. Shephard, slab sinking rates, regional plate reconstructions, and satellite-derived gravity gradients. Our preferred [email protected] interpretation stipulates that anomalous, fast seismic velocities at 1000–1600 km depth imaged in independent global tomographic models, coupled with gravity gradient perturbations, represent paleo-Arctic oceanic slabs Citation: that subducted in the Mesozoic. We suggest a novel connection between slab-related arc mantle and Shephard, G. E., R. G. Trønnes, geochemical signatures in some of the tholeiitic and mildly alkaline magmas of the Cretaceous High Arctic W. -
Arctic Ocean Outflow and Glacier-Ocean Interaction Modify Water Over the Wandel Sea Shelf
Ocean Sci. Discuss., doi:10.5194/os-2017-28, 2017 Manuscript under review for journal Ocean Sci. Discussion started: 20 April 2017 c Author(s) 2017. CC-BY 3.0 License. Arctic Ocean outflow and glacier-ocean interaction modify water over the Wandel Sea shelf, northeast Greenland Igor A. Dmitrenko1*, Sergei A. Kirillov1, Bert Rudels2, David G. Babb1, Leif Toudal Pedersen3, Søren 5 Rysgaard1,4,5, Yngve Kristoffersen6,7 and David G. Barber1 1Centre for Earth Observation Science, University of Manitoba, Winnipeg, Canada 2Finnish Meteorological Institute, Helsinki, Finland 3Danish Meteorological Institute, Copenhagen, Denmark 10 4Greenland Climate Research Centre, Greenland Institute of Natural Resources, Nuuk, Greenland 5Arctic Research Centre, Aarhus University, Aarhus, Denmark 6Department of Earth Science, University of Bergen, Bergen, Norway 7 Nansen Environmental and Remote Sensing Centre, Bergen, Norway 15 *Corresponding author, e-mail: [email protected] Abstract: The first-ever conductivity-temperature-depth (CTD) observations on the Wandel Sea shelf in North Eastern Greenland were collected in April-May 2015. They were complemented by CTD profiles taken along the continental slope during the Norwegian FRAM 2014-15 drift. The CTD profiles 1 Ocean Sci. Discuss., doi:10.5194/os-2017-28, 2017 Manuscript under review for journal Ocean Sci. Discussion started: 20 April 2017 c Author(s) 2017. CC-BY 3.0 License. 20 are used to reveal the origin of water masses and interactions with ambient water from the continental slope and the outlet glaciers. The subsurface water is associated with the Pacific Water outflow from the Arctic Ocean. The underlying Halocline separates the Pacific Water from a deeper layer of Polar Water that has interacted with the warm Atlantic water outflow through Fram Strait recorded below 140 m. -
Arctic Geopolitics, Media and Power
Arctic Geopolitics, Media and Power Arctic Geopolitics, Media and Power provides a fresh way of looking at the potential and limitations of regional international governance in the Arctic region. Far-reaching impacts of climate change, its wealth of resources and poten- tial for new commercial activities have placed the Arctic region into the political limelight. In an era of rapid environmental change, the Arctic provides a complex and challenging case of geopolitical interplay. Based on analyses of how actors from within and outside the Arctic region assert their interests and how such dis- courses travel in the media, this book scrutinizes the social and material contexts within which new imaginaries, spatial constructs and scalar preferences emerge. It places ground-breaking attention to shifting media landscapes as a critical com- ponent of the social, environmental and technological change. It also reflects on the fundamental dilemmas inherent in democratic decision making at a time when an urgent need for addressing climate change is challenged by conflicting interests and growing geopolitical tensions. This book will be of great interest to geography academics, media and commu- nication studies and students focusing on policy, climate change and geopolitics, as well as policy-makers and NGOs working within the environmental sector or with the Arctic region. Annika E Nilsson is a researcher at KTH Royal Institute of Technology. Her work focuses on the politics of Arctic change and communication at the science– policy interface. Nilsson was previously at the Stockholm Environment Institute. Miyase Christensen is Professor of Media and Communication Studies at Stockholm University and is an affiliated researcher at KTH the Royal Institute of Technology. -
AAR Chapter 2
Go back to opening screen 9 Chapter 2 Physical/Geographical Characteristics of the Arctic –––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– Contents 2.2.1. Climate boundaries 2.1. Introduction . 9 On the basis of temperature, the Arctic is defined as the area 2.2. Definitions of the Arctic region . 9 2.2.1. Climate boundaries . 9 north of the 10°C July isotherm, i.e., north of the region 2.2.2. Vegetation boundaries . 9 which has a mean July temperature of 10°C (Figure 2·1) 2.2.3. Marine boundary . 10 (Linell and Tedrow 1981, Stonehouse 1989, Woo and Gre- 2.2.4. Geographical coverage of the AMAP assessment . 10 gor 1992). This isotherm encloses the Arctic Ocean, Green- 2.3. Climate and meteorology . 10 2.3.1. Climate . 10 land, Svalbard, most of Iceland and the northern coasts and 2.3.2. Atmospheric circulation . 11 islands of Russia, Canada and Alaska (Stonehouse 1989, 2.3.3. Meteorological conditions . 11 European Climate Support Network and National Meteoro- 2.3.3.1. Air temperature . 11 2.3.3.2. Ocean temperature . 12 logical Services 1995). In the Atlantic Ocean west of Nor- 2.3.3.3. Precipitation . 12 way, the heat transport of the North Atlantic Current (Gulf 2.3.3.4. Cloud cover . 13 Stream extension) deflects this isotherm northward so that 2.3.3.5. Fog . 13 2.3.3.6. Wind . 13 only the northernmost parts of Scandinavia are included. 2.4. Physical/geographical description of the terrestrial Arctic 13 Cold water and air from the Arctic Ocean Basin in turn 2.4.1. -
Laptev Sea System
Russian-German Cooperation: Laptev Sea System Edited by Heidemarie Kassens, Dieter Piepenburg, Jör Thiede, Leonid Timokhov, Hans-Wolfgang Hubberten and Sergey M. Priamikov Ber. Polarforsch. 176 (1995) ISSN 01 76 - 5027 Russian-German Cooperation: Laptev Sea System Edited by Heidemarie Kassens GEOMAR Research Center for Marine Geosciences, Kiel, Germany Dieter Piepenburg Institute for Polar Ecology, Kiel, Germany Jör Thiede GEOMAR Research Center for Marine Geosciences, Kiel. Germany Leonid Timokhov Arctic and Antarctic Research Institute, St. Petersburg, Russia Hans-Woifgang Hubberten Alfred-Wegener-Institute for Polar and Marine Research, Potsdam, Germany and Sergey M. Priamikov Arctic and Antarctic Research Institute, St. Petersburg, Russia TABLE OF CONTENTS Preface ....................................................................................................................................i Liste of Authors and Participants ..............................................................................V Modern Environment of the Laptev Sea .................................................................1 J. Afanasyeva, M. Larnakin and V. Tirnachev Investigations of Air-Sea Interactions Carried out During the Transdrift II Expedition ............................................................................................................3 V.P. Shevchenko , A.P. Lisitzin, V.M. Kuptzov, G./. Ivanov, V.N. Lukashin, J.M. Martin, V.Yu. ßusakovS.A. Safarova, V. V. Serova, ßvan Grieken and H. van Malderen The Composition of Aerosols -
Arctic Ocean Outflow and Glacier-Ocean Interaction Modify Water Over the Wandel Sea Shelf
1 1 Arctic Ocean outflow and glacier-ocean interaction modify water over the Wandel Sea shelf 2 (Northeast Greenland) 3 4 5 Igor A. Dmitrenko1*, Sergey A. Kirillov1, Bert Rudels2, David G. Babb1, Leif Toudal Pedersen3, Søren 6 Rysgaard1,4,5, Yngve Kristoffersen6,7 and David G. Barber1 7 8 9 1Centre for Earth Observation Science, University of Manitoba, Winnipeg, Canada 10 2Finnish Meteorological Institute, Helsinki, Finland 11 3 Technical University of Denmark, Lyngby, Denmark 12 4Greenland Climate Research Centre, Greenland Institute of Natural Resources, Nuuk, Greenland 13 5Arctic Research Centre, Aarhus University, Aarhus, Denmark 14 6Department of Earth Science, University of Bergen, Bergen, Norway 15 7 Nansen Environmental and Remote Sensing Centre, Bergen, Norway 16 17 18 19 20 21 22 *Corresponding author, e-mail: [email protected] 2 23 Abstract: The first-ever conductivity-temperature-depth (CTD) observations on the Wandel Sea shelf in 24 North Eastern Greenland were collected in April-May 2015. They were complemented by CTDs taken 25 along the continental slope during the Norwegian FRAM 2014-15 drift. The CTD profiles are used to 26 reveal the origin of water masses and interactions with ambient water from the continental slope and the 27 tidewater glacier outlet. The subsurface water is associated with the Pacific Water outflow from the Arctic 28 Ocean. The underlying Halocline separates the Pacific Water from a deeper layer of Polar Water that has 29 interacted with the warm Atlantic water outflow through Fram Strait recorded below 140 m. Over the outer 30 shelf, the Halocline shows numerous cold density-compensated intrusions indicating lateral interaction with 31 an ambient Polar Water mass across the continental slope. -
The Mesozoic–Cenozoic Tectonic Evolution of the New Siberian Islands, NE Russia
Geol. Mag. 152 (3), 2015, pp. 480–491. c Cambridge University Press 2014 480 doi:10.1017/S0016756814000326 The Mesozoic–Cenozoic tectonic evolution of the New Siberian Islands, NE Russia ∗ CHRISTIAN BRANDES †, KARSTEN PIEPJOHN‡, DIETER FRANKE‡, NIKOLAY SOBOLEV§ & CHRISTOPH GAEDICKE‡ ∗ Institut für Geologie, Leibniz Universität Hannover, Callinstraße, 30167 Hannover, Germany ‡Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Stilleweg 2, 30655 Hannover, Germany §A.P. Karpinsky Russian Geological Research Institute (VSEGEI), Sredny av. 74, 199106 Saint-Petersburg, Russia (Received 27 December 2013; accepted 4 June 2014; first published online 25 September 2014) Abstract – On the New Siberian Islands the rocks of the east Russian Arctic shelf are exposed and allow an assessment of the structural evolution of the region. Tectonic fabrics provide evidence of three palaeo-shortening directions (NE–SW, WNW–ESE and NNW–SSE to NNE–SSW) and one set of palaeo-extension directions revealed a NE–SW to NNE–SSW direction. The contractional deformation is most likely the expression of the Cretaceous formation of the South Anyui fold–thrust belt. The NE–SW shortening is the most prominent tectonic phase in the study area. The WNW–ESE and NNW–SSE to NNE–SSW-oriented palaeo-shortening directions are also most likely related to fold belt formation; the latter might also have resulted from a bend in the suture zone. The younger Cenozoic NE–SW to NNE–SSW extensional direction is interpreted as a consequence of rifting in the Laptev Sea. Keywords: New Siberian Islands, De Long Islands, South Anyui suture zone, fold–thrust belt. 1. Introduction slip data. Such datasets deliver important information for understanding the regional geodynamic evolution In the last decades, several plate tectonic models have of the study area.