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Proceedings of the Open University Geological Society
0 OUGS Proceedings 5 2019_OUGSJ 26/02/2019 11:45 Page i Proceedings of the Open University Geological Society Volume 5 2019 Including articles from the AGM 2018 Geoff Brown Memorial Lecture, the ‘Music of the Earth’ Symposium 2018 lectures (Worcester University), OUGS Members’ field trip reports, the Annual Report for 2018, and the 2018 Moyra Eldridge Photographic Competition Winning and Highly Commended photographs Edited and designed by: Dr David M. Jones 41 Blackburn Way, Godalming, Surrey GU7 1JY e-mail: [email protected] The Open University Geological Society (OUGS) and its Proceedings Editor accept no responsibility for breach of copyright. Copyright for the work remains with the authors, but copyright for the published articles is that of the OUGS. ISSN 2058-5209 © Copyright reserved Proceedings of the OUGS 5 2019; published 2019; printed by Hobbs the Printers Ltd, Totton, Hampshire 0 OUGS Proceedings 5 2019_OUGSJ 26/02/2019 11:46 Page 35 The complex tectonic evolution of the Malvern region: crustal accretion followed by multiple extensional and compressional reactivation Tim Pharaoh British Geological Survey, Keyworth, Nottingham, NG12 5GG ([email protected]) Abstract The Malvern Hills include some of the oldest rocks in southern Britain, dated by U-Pb zircon analysis to c. 680Ma. They reflect calc- alkaline arc magmatic activity along a margin of the Rodinia palaeocontinent, hints of which are provided by inherited zircon grains as old as 1600Ma. Metamorphic recrystallisation under upper greenschist/amphibolite facies conditions occurred from c. 650–600Ma. Subsequently, rifting of the magmatic arc (c.f. the modern western Pacific) at c. 565Ma led to the formation of a small oceanic mar- ginal basin, evidenced by basaltic pillow lavas and tuffs of the Warren House Formation, and Kempsey Formation equivalents beneath the Worcester Graben. -
The North-Subducting Rheic Ocean During the Devonian: Consequences for the Rhenohercynian Ore Sites
Published in "International Journal of Earth Sciences 106(7): 2279–2296, 2017" which should be cited to refer to this work. The north-subducting Rheic Ocean during the Devonian: consequences for the Rhenohercynian ore sites Jürgen F. von Raumer1 · Heinz-Dieter Nesbor2 · Gérard M. Stampfli3 Abstract Base metal mining in the Rhenohercynian Zone activated Early Devonian growth faults. Hydrothermal brines has a long history. Middle-Upper Devonian to Lower Car- equilibrated with the basement and overlying Middle-Upper boniferous sediment-hosted massive sulfide deposits Devonian detrital deposits forming the SHMS deposits in the (SHMS), volcanic-hosted massive sulfide deposits (VHMS) southern part of the Pyrite Belt, in the Rhenish Massif and and Lahn-Dill-type iron, and base metal ores occur at sev- in the Harz areas. Volcanic-hosted massive sulfide deposits eral sites in the Rhenohercynian Zone that stretches from the (VHMS) formed in the more eastern localities of the Rheno- South Portuguese Zone, through the Lizard area, the Rhen- hercynian domain. In contrast, since the Tournaisian period ish Massif and the Harz Mountain to the Moravo-Silesian of ore formation, dominant pull-apart triggered magmatic Zone of SW Bohemia. During Devonian to Early Carbonif- emplacement of acidic rocks, and their metasomatic replace- erous times, the Rhenohercynian Zone is seen as an evolv- ment in the apical zones of felsic domes and sediments in ing rift system developed on subsiding shelf areas of the the northern part of the Iberian Pyrite belt, thus changing the Old Red continent. A reappraisal of the geotectonic setting general conditions of ore precipitation. -
Sticta Arctica Degel.] Arctic Moon Habitat/Range: Over Mosses and Mossy Rocks in Alpine Localities; N Am – Eastern Eurasia, N to AK, S to OR
STICTA/UMBILICARIA [Sticta arctica Degel.] Arctic moon Habitat/Range: Over mosses and mossy rocks in alpine localities; N Am – eastern Eurasia, N to AK, S to OR. Reaction: All spot tests negative. Contents: No lichen substances reported. Notes: Not recorded from B.C., but known to occur in southern coastal Alaska only a few kilometres from the B.C. border. Sticta fuliginosa (Hoffm.) Ach. Peppered moon (sooty leather lichen) Habitat/Range: Frequent over deciduous trees and conifers, also over mossy rock, in humid forests at lower eleva- tions throughout, except absent from boreal regions; incompletely circumpolar, N to AK, S to CA. Reaction: All spot tests negative. Contents: No lichen substances reported. Sticta limbata (Sm.) Ach. Powdered moon Habitat/Range: Infrequent over deciduous trees and especially mossy rock in open coastal forests at lower eleva- tions, also rare in intermontane (ICH zone); western N Am – eastern N Am – western Eurasia, N to AK, S to CA. Reactions: All spot tests negative. Contents: No lichen substances reported. Sticta weigelii (Ach.) Vainio Map 107 Fringed moon (Weigel’s leather lichen) Habitat/Range: Rare over trees and shrubs in open coastal forests at lower elevations; western N Am – eastern N Am – eastern Eurasia, N to AK, S to CA. Reactions: All spot tests negative. Contents: No lichen substances reported. Sticta wrightii Tuck. Map 108 Green moon Habitat/Range: Rare over conifers in semi-shady intermontane old-growth forests at lower elevations; western N Am – eastern Eurasia, N to AK, S to BC. Reactions: All spot tests negative. Contents: No lichen substances reported. Sticta sp. -
The Influence of Climatic Change and Human Activity on Erosion Processes in Sub-Arid Watersheds in Southern East Siberia
HYDROLOGICAL PROCESSES Hydrol. Process. 17, 3181–3193 (2003) Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/hyp.1382 The influence of climatic change and human activity on erosion processes in sub-arid watersheds in southern East Siberia Leonid M. Korytny,* Olga I. Bazhenova, Galina N. Martianova and Elena A. Ilyicheva Institute of Geography, Siberian Branch of the Russian Academy of Sciences, 1 Ulanbatorskaya St., Irkutsk, 664033, Russia Abstract: A LUCIFS model variant is presented that represents the influence of climate and land use change on fluvial systems. The study considers trends of climatic characteristics (air temperature, annual precipitation totals, rainfall erosion index, aridity and continentality coefficients) for the steppe and partially wooded steppe watersheds of the south of East Siberia (the Yenisey River macro-watershed). It also describes the influence of these characteristics on erosion processes, one indicator of which is the suspended sediment yield. Changes in the river network structure (the order of rivers, lengths, etc.) as a result of agricultural activity during the 20th century are investigated by means of analysis of maps of different dates for one of the watersheds, that of the Selenga River, the biggest tributary of Lake Baikal. The study reveals an increase of erosion process intensity in the first two-thirds of the century in the Selenga River watershed and a reduction of this intensity in the last third of the century, both in the Selenga River watershed and in most of the other watersheds of the study area. Copyright 2003 John Wiley & Sons, Ltd. KEY WORDS LUCIFS; Yenisey watershed; fluvial system; climate change; land use change; river network structure; erosion processes. -
The Geology of England – Critical Examples of Earth History – an Overview
The Geology of England – critical examples of Earth history – an overview Mark A. Woods*, Jonathan R. Lee British Geological Survey, Environmental Science Centre, Keyworth, Nottingham, NG12 5GG *Corresponding Author: Mark A. Woods, email: [email protected] Abstract Over the past one billion years, England has experienced a remarkable geological journey. At times it has formed part of ancient volcanic island arcs, mountain ranges and arid deserts; lain beneath deep oceans, shallow tropical seas, extensive coal swamps and vast ice sheets; been inhabited by the earliest complex life forms, dinosaurs, and finally, witnessed the evolution of humans to a level where they now utilise and change the natural environment to meet their societal and economic needs. Evidence of this journey is recorded in the landscape and the rocks and sediments beneath our feet, and this article provides an overview of these events and the themed contributions to this Special Issue of Proceedings of the Geologists’ Association, which focuses on ‘The Geology of England – critical examples of Earth History’. Rather than being a stratigraphic account of English geology, this paper and the Special Issue attempts to place the Geology of England within the broader context of key ‘shifts’ and ‘tipping points’ that have occurred during Earth History. 1. Introduction England, together with the wider British Isles, is blessed with huge diversity of geology, reflected by the variety of natural landscapes and abundant geological resources that have underpinned economic growth during and since the Industrial Revolution. Industrialisation provided a practical impetus for better understanding the nature and pattern of the geological record, reflected by the publication in 1815 of the first geological map of Britain by William Smith (Winchester, 2001), and in 1835 by the founding of a national geological survey. -
Biometric Comparisons Between North American and European Mammals
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Faculty Publications from the Harold W. Manter Laboratory of Parasitology Parasitology, Harold W. Manter Laboratory of 1959 Biometric Comparisons between North American and European Mammals. I. A Comparison between Alaskan and Fennoscandian Wolverine (Gulo gulo Linnaeus) Björn Kurtén Institute of Geology and Paleontology of Helsingfors University Robert L. Rausch Arctic Health Research Center, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/parasitologyfacpubs Part of the Parasitology Commons Kurtén, Björn and Rausch, Robert L., "Biometric Comparisons between North American and European Mammals. I. A Comparison between Alaskan and Fennoscandian Wolverine (Gulo gulo Linnaeus)" (1959). Faculty Publications from the Harold W. Manter Laboratory of Parasitology. 532. https://digitalcommons.unl.edu/parasitologyfacpubs/532 This Article is brought to you for free and open access by the Parasitology, Harold W. Manter Laboratory of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Faculty Publications from the Harold W. Manter Laboratory of Parasitology by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Björn Kurtén & Robert L. Rausch in Acta Arctica (1959) Fasc. XI. BIOMETRIC COMPARISONS BETWEEN NORTH AMERICAN AND EUROPEAN MAMMALS 1. A COMPARISON BETWEEN ALASK.AN AND FENNOSCANDIAN WOLVERINE (GULO GULO LINNAEUS) INTRODUCTION The taxonomy ofmany circumpolar mammals is not at present in a satis(;lctory state. Whercas many European students favour the circumpolar species concept, the approach or Amnican students has often had a provincial tinge. This attitude has been criticized by one ofus (IC\t:SCII, '953)· This holds also for the wolverine or glutton, subject ofthe present study: DEGER""!. -
Mapping a Hidden Terrane Boundary in the Mantle Lithosphere with Lamprophyres
ARTICLE DOI: 10.1038/s41467-018-06253-7 OPEN Mapping a hidden terrane boundary in the mantle lithosphere with lamprophyres Arjan H. Dijkstra 1 & Callum Hatch1,2 Lamprophyres represent hydrous alkaline mantle melts that are a unique source of information about the composition of continental lithosphere. Throughout southwest Britain, post-Variscan lamprophyres are (ultra)potassic with strong incompatible element enrich- 1234567890():,; ments. Here we show that they form two distinct groups in terms of their Sr and Nd isotopic compositions, occurring on either side of a postulated, hitherto unrecognized terrane boundary. Lamprophyres emplaced north of the boundary fall on the mantle array with εNd −1 to +1.6. Those south of the boundary are enriched in radiogenic Sr, have initial εNd values of −0.3 to −3.5, and are isotopically indistinguishable from similar-aged lamprophyres in Armorican massifs in Europe. We conclude that an Armorican terrane was juxtaposed against Avalonia well before the closure of the Variscan oceans and the formation of Pangea. The giant Cornubian Tin-Tungsten Ore Province and associated batholith can be accounted for by the fertility of Armorican lower crust and mantle lithosphere. 1 School of Geography, Earth and Environmental Sciences, Plymouth University, Plymouth PL4 8AA, UK. 2 Department of Core Research Laboratories, Natural History Museum, Cromwell Road, London, SW7 5BD UK. Correspondence and requests for materials should be addressed to A.H.D. (email: [email protected]) NATURE COMMUNICATIONS | (2018) 9:3770 | DOI: 10.1038/s41467-018-06253-7 | www.nature.com/naturecommunications 1 ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/s41467-018-06253-7 ilson’s cycle1 of the opening and closing of ocean typically form 10 cm to m-wide dykes and other types of minor Wbasins throughout Earth history was based on the intrusions cutting across Variscan foliations in Carboniferous and similarity of Early Palaeozoic faunal assemblages in Devonian rocks. -
European Red List of Birds
European Red List of Birds Compiled by BirdLife International Published by the European Commission. opinion whatsoever on the part of the European Commission or BirdLife International concerning the legal status of any country, Citation: Publications of the European Communities. Design and layout by: Imre Sebestyén jr. / UNITgraphics.com Printed by: Pannónia Nyomda Picture credits on cover page: Fratercula arctica to continue into the future. © Ondrej Pelánek All photographs used in this publication remain the property of the original copyright holder (see individual captions for details). Photographs should not be reproduced or used in other contexts without written permission from the copyright holder. Available from: to your questions about the European Union Freephone number (*): 00 800 6 7 8 9 10 11 (*) Certain mobile telephone operators do not allow access to 00 800 numbers or these calls may be billed Published by the European Commission. A great deal of additional information on the European Union is available on the Internet. It can be accessed through the Europa server (http://europa.eu). Cataloguing data can be found at the end of this publication. ISBN: 978-92-79-47450-7 DOI: 10.2779/975810 © European Union, 2015 Reproduction of this publication for educational or other non-commercial purposes is authorized without prior written permission from the copyright holder provided the source is fully acknowledged. Reproduction of this publication for resale or other commercial purposes is prohibited without prior written permission of the copyright holder. Printed in Hungary. European Red List of Birds Consortium iii Table of contents Acknowledgements ...................................................................................................................................................1 Executive summary ...................................................................................................................................................5 1. -
Tectonic Evolution of the Northern Ural Orogen
Journal of the Geological Society, London, Vol. 152, 1995, pp. 903-906, 5 figs. Printed in Northern Ireland compression in the Early Devonian led to the inversion of the Timan and Varandey-Adz'va rifts to form ridges, which Tectonic evolution of the northern Ural acted as the source for the Middle Devonian clastic rocks Orogen found in the Timan-Pechora Basin. However, by the mid-Frasnian, shallow marine conditions were re- established, with carbonates deposited on highs and S. C. OTTO 1 & R. J. BAILEY 2 'Domanik' facies organic-rich shales laid down in the lPetroconsultants (UK) Ltd, 266 Upper Richmond intervening lows. Road, London SW15 6TQ, UK Closure of the ocean began in the Tournaisian, and 2Victoria Villa, 5 Station Road, Southwell, eastward subduction under the Siberian craton is made Nottinghamshire NG25 OET, UK evident by basement of volcanic island arc affinity found only to the east of the Urals (Churkin et al. 1981). In the Timan-Pechora Basin, the transpressional reactivation of faults resulted in the complete inversion of the earlier rifts. Local highs were formed, such as the Usa and Vozey highs, The closure of the Uralian Ocean occurred in Early Permian-Early which were a source of clastics during the Late Triassic time. In the northern Ural fold belt, overthrusting to the Tournaisian-Early Visean. Throughout the remainder of west produced a major foreland basin to the west of the mountain chain. In contrast, in the northern extension of the Ural Orogen, the Carboniferous and into the earliest Permian, the basin the Taymyr fold belt, thrusting was directed to the SE. -
The Iberian Variscan Orogen
CHAPTER 1 THE IBERIAN VARISCAN OROGEN Aerial view of the tectonic repetition of limestone beds in the Láncara Formation, Primajas duplex structure of the Esla thrust (photo by J.L. Alonso) Martínez Catalán, J.R. Aller, J. Alonso, J.L. Bastida, F. Rocks of Upper Proterozoic to Carboniferous age - forming the Variscan or Hercynian orogen - crop out widely in the western part of the Iberian Peninsula, in what is called the Iberian or Hesperian Massif. These deformed rocks, often metamorphosed and intruded by different types of granitoids, were witness to the great mountain range formed in the late Paleozoic, basically in the Late Devonian and Carboniferous (between 370 and 290 million years ago), by the convergence and collision of two major continents: Laurasia and Gondwana. The Iberian Massif constitutes a geological framework of global interest. It is unique due to the continuity of its exposures and because it displays excellent records allowing the analysis of continental crust features, the tectonic, metamorphic and magmatic evolution of orogens, and therefore provides enormously relevant data about the lithospheric dynamics during the latest Precambrian and the Paleozoic. The Variscan orogen forms the basement of the Figure 1. Scheme showing the position of the Iberian Iberian Peninsula and of most of western and central Peninsula in relation to the Appalachians and the Europe. A crustal basement is the result of an orog- Caledonian and Variscan belts. Modified from eny, that is, the consequence of a deep remobilization Neuman and Max (1989). of the continental crust caused by the convergence of plates, and is associated to uplift and the creation of relief. -
Ages of Detrital Zircons (U/Pb, LA-ICP-MS) from the Latest
Precambrian Research 244 (2014) 288–305 Contents lists available at ScienceDirect Precambrian Research jo urnal homepage: www.elsevier.com/locate/precamres Ages of detrital zircons (U/Pb, LA-ICP-MS) from the Latest Neoproterozoic–Middle Cambrian(?) Asha Group and Early Devonian Takaty Formation, the Southwestern Urals: A test of an Australia-Baltica connection within Rodinia a,∗ b c Nikolay B. Kuznetsov , Joseph G. Meert , Tatiana V. Romanyuk a Geological Institute, Russian Academy of Sciences, Pyzhevsky Lane, 7, Moscow 119017, Russia b Department of Geological Sciences, University of Florida, 355 Williamson Hall, Gainesville, FL 32611, USA c Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, B. Gruzinskaya ul. 10, Moscow 123810, Russia a r t i c l e i n f o a b s t r a c t Article history: A study of U-Pb ages on detrital zircons derived from sedimentary sequences in the western flank of Received 5 February 2013 Urals (para-autochthonous or autochthonous with Baltica) was undertaken in order to ascertain/test Received in revised form source models and paleogeography of the region in the Neoproterozoic. Samples were collected from the 16 September 2013 Ediacaran-Cambrian(?) age Asha Group (Basu and Kukkarauk Formations) and the Early Devonian-aged Accepted 18 September 2013 Takaty Formation. Available online 19 October 2013 Ages of detrital zircons within the Basu Formation fall within the interval 2900–700 Ma; from the Kukkarauk Formation from 3200 to 620 Ma. Ages of detrital zircons from the Devonian age Takaty For- Keywords: Australia mation are confined to the Paleoproterozoic and Archean (3050–1850 Ma). -
4: Potential Mineral Resources in Antarctica
Chapter 4 Potential Mineral Resources in Antarctica Photo credit: U.S. Geological Survey Byrd Glacier CONTENTS Page SUMMARY . 93 INTRODUCTION . 93 GEOLOGICAL ASSOCIATIONS . 96 Relationship to Adjacent Continents . 99 Offshore Shelf Areas . 102 ANTARCTICA IN THE CONTEXT OF FUTURE MINERALS SUPPLY . 103 Prospecting and Exploration in Antarctica . 105 Probabilities of Discovering Antarctic Mineral Deposits . 110 SELECTED MINERAL RESOURCES ● . 111 Oil and Gas . .. 111 coal . .114 Uranium . 114 Chromium . .115 Copper . 116 Gold . 117 Iron . .118 Molybdenum . .119 Platinum-Group Metals . .119 Rare-Earth Metals . .120 Diamonds . .. 122 Boxes Box Page 4-A. Mineral Resources and Reserves . 95 4-B. Geologic Time Scale . 98 4-C. Icebergs . 121 Figures Figure Page 4-1. Antarctic Mineral Occurrences . 97 4-2. Geologic Provinces of Antarctica and Their Relationship to Adjacent Gondwana Continents . 100 4-3. Reconstruction of Gondwana in Early Cretaceus Time . 103 4-4. Exposed Rock Outcrop in Antarctica . .. 106 4-5. What Antarctica Would Look Like If the Ice Were Removed . 107 4-6. Multichannel Seismic Data . .. 108 4-7. Sedimentary Basins in Antarctica . ,.. , 112 Tables Table Page 4-1. Desirable Research for Evaluating Resource Potential of Antarctica . 110 4-2. Research Required To Ensure That Petroleum Resources Are Safely and Efficiently Recovered With Minimum Environmental Impact . 110 4-3. Estimated Number of Major Mineral Deposits in Antarctica . 112 Chapter 4 Potential Mineral Resources in Antarctica SUMMARY The offshore sedimentary basins surrounding Antarctica offer the best prospects for petroleum Scientists have discovered occurrences (small exploration. The Weddell and Ross embayments in amounts) of several minerals in Antarctica, but West Antarctica, and Prydz Bay and the Wilkes there are no known mineral deposits of commer- Basin in East Antarctica are among the basins most cial interest.