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The Last Maximum Ice Extent and Subsequent Deglaciation of the Pyrenees: an Overview of Recent Research
Cuadernos de Investigación Geográfica 2015 Nº 41 (2) pp. 359-387 ISSN 0211-6820 DOI: 10.18172/cig.2708 © Universidad de La Rioja THE LAST MAXIMUM ICE EXTENT AND SUBSEQUENT DEGLACIATION OF THE PYRENEES: AN OVERVIEW OF RECENT RESEARCH M. DELMAS Université de Perpignan-Via Domitia, UMR 7194 CNRS, Histoire Naturelle de l’Homme Préhistorique, 52 avenue Paul Alduy 66860 Perpignan, France. ABSTRACT. This paper reviews data currently available on the glacial fluctuations that occurred in the Pyrenees between the Würmian Maximum Ice Extent (MIE) and the beginning of the Holocene. It puts the studies published since the end of the 19th century in a historical perspective and focuses on how the methods of investigation used by successive generations of authors led them to paleogeographic and chronologic conclusions that for a time were antagonistic and later became complementary. The inventory and mapping of the ice-marginal deposits has allowed several glacial stades to be identified, and the successive ice boundaries to be outlined. Meanwhile, the weathering grade of moraines and glaciofluvial deposits has allowed Würmian glacial deposits to be distinguished from pre-Würmian ones, and has thus allowed the Würmian Maximum Ice Extent (MIE) –i.e. the starting point of the last deglaciation– to be clearly located. During the 1980s, 14C dating of glaciolacustrine sequences began to indirectly document the timing of the glacial stades responsible for the adjacent frontal or lateral moraines. Over the last decade, in situ-produced cosmogenic nuclides (10Be and 36Cl) have been documenting the deglaciation process more directly because the data are obtained from glacial landforms or deposits such as boulders embedded in frontal or lateral moraines, or ice- polished rock surfaces. -
The Eemian - Local Sequences, Global Perspectives: Introduction
Geologie en Mijnbouw / Netherlands Journal of Geosciences 79 (2/3): 129-133 (2000) The Eemian - local sequences, global perspectives: introduction Thijs van Kolfschoten1 & Philip L. Gibbard2 1 Faculty of Archaeology, Leiden University, P.O. Box 9515, 2300 RA LEIDEN, the Netherlands; Corresponding author; e-mail: [email protected] 2 Godwin Institute of Quaternary Research, Department of Geography, University of Cambridge, Downing Street, CAMBRIDGE CB2 3EN, England; e-mail:[email protected] Received: May 2000; accepted in revised form: 20 June 2000 G The history of this special issue gation and discussion on the Middle/Late Pleistocene boundary on the original type area of the Eemian in The history of this volume goes back to a 1973 IN- the Netherlands. The Eemian sequence was often QUA congress in New Zealand, where an INQUA used as reference and furthermore the term 'Eemian' Commission of Stratigraphy working group on major was widely used to identify the last interglacial far be subdivisions of the Pleistocene was established. The yond western central Europe. Examination of the Pleistocene series/epoch was hitherto generally subdi available data from the Eemian type area showed that vided into the Lower/Early, Middle and Upper/Late a re-evaluation of existing data and collection of criti Pleistocene (see, among others, Zeuner, 1935, 1959) cal new data were needed to define an unambiguous but the boundaries between these subseries/sube- stratigraphical boundary. Although the identification pochs were not formally defined. The boundary be of boundaries is central to stratigraphical subdivision, tween the Early and Middle Pleistocene was, in the it is nevertheless the Eemian as an entity that is of European literature, put at the base of the Cromerian particular interest for understanding the development Complex (Zagwijn, 1963) or at the Brunhes/Matuya- of a complete interglacial cycle. -
Active Faulting Geometry and Stress
Tectonics RESEARCH ARTICLE Active Faulting Geometry and Stress Pattern Near Complex 10.1029/2018TC004983 Strike-Slip Systems Along the Maghreb Region: Special Section: Constraints on Active Convergence Geodynamics, Crustal and Lithospheric Tectonics, and in the Western Mediterranean active deformation in the Mediterranean Regions Abdelkader Soumaya1,2 , Noureddine Ben Ayed3, Mojtaba Rajabi4 , Mustapha Meghraoui5, (A tribute to Prof. Renato Damien Delvaux6, Ali Kadri3, Moritz Ziegler7,8 , Said Maouche9, and Ahmed Braham2 Funiciello) 1Faculty of Sciences Tunis, University of Manar, Tunis, Tunisia, 2National Office of Mines, Tunisia, 3Faculty of Sciences Bizerte, 4 Key Points: University of Carthage, Tunis, Tunisia, Australian School of Petroleum, University of Adelaide, Adelaide, South Australia, • Maghreb region is characterized by Australia, 5Institut de Physique du Globe de Strasbourg (UMR 7516), Strasbourg, France, 6Earth Sciences Department, Royal different geometries of active Museum for Central Africa, Tervuren, Belgium, 7Helmholtz Centre Potsdam, German Research Centre for Geosciences GFZ, strike-slip faults Potsdam, Germany, 8Institute of Earth and Environmental Science, University of Potsdam, Potsdam, Germany, 9CRAAG, • Present-day active contraction on western Africa-Eurasia boundary is Bouzareah-Alger, Algeria accommodated by a combination of strike-slip and thrust faulting • Second-order tectonic regime across Abstract The Maghreb region (from Tunisia to Gibraltar) is a key area in the western Mediterranean to Maghreb varies with clockwise study the active tectonics and stress pattern across the Africa-Eurasia convergent plate boundary. In the rotation of S from east to west Hmax present study, we compile comprehensive data set of well-constrained crustal stress indicators (from single focal mechanism solutions, formal inversion of focal mechanism solutions, and young geologic fault slip data) based on our and published data analyses. -
Africa-Arabia-Eurasia Plate Interactions and Implications for the Dynamics of Mediterranean Subduction and Red Sea Rifting
This page added by the GeoPRISMS office. Africa-Arabia-Eurasia plate interactions and implications for the dynamics of Mediterranean subduction and Red Sea rifting Authors: R. Reilinger, B. Hager, L. Royden, C. Burchfiel, R. Van der Hilst Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA USA, [email protected], Tel: (617)253 -7860 This page added by the GeoPRISMS office. Our proposed GeoPRISMS Initiative is based on the premise that understanding the mechanics of plate motions (i.e., the force balance on the plates) is necessary to develop realistic models for plate interactions, including processes at subduction and extensional (rifting) plate boundaries. Important advances are being made with new geologic and geophysical techniques and observations that are providing fundamental insights into the dynamics of these plate tectonic processes. Our proposed research addresses directly the following questions identified in the GeoPRISMS SCD Draft Science Plan: 4.2 (How does deformation across the subduction plate boundary evolve in space and time, through the seismic cycle and beyond?), 4.6 (What are the physical and chemical conditions that control subduction zone initiation and the development of mature arc systems?), and 4.7 (What are the critical feedbacks between surface processes and subduction zone mechanics and dynamics?). It has long been recognized that the Greater Mediterranean region provides a natural laboratory to study a wide range of geodynamic processes (Figure 1) including ocean subduction and continent- continent collision (Hellenic arc, Arabia-Eurasia collision), lithospheric delamination (E Turkey High Plateau, Alboran Sea/High Atlas), back-arc extension (Mediterranean basins, including Alboran, Central Mediterranean, Aegean), “escape” tectonics and associated continental transform faulting (Anatolia, North and East Anatolian faults), and active continental and ocean rifting (East African and northern Red Sea rifting, central Red Sea and Gulf of Aden young ocean rifting). -
Marine Mammals and Sea Turtles of the Mediterranean and Black Seas
Marine mammals and sea turtles of the Mediterranean and Black Seas MEDITERRANEAN AND BLACK SEA BASINS Main seas, straits and gulfs in the Mediterranean and Black Sea basins, together with locations mentioned in the text for the distribution of marine mammals and sea turtles Ukraine Russia SEA OF AZOV Kerch Strait Crimea Romania Georgia Slovenia France Croatia BLACK SEA Bosnia & Herzegovina Bulgaria Monaco Bosphorus LIGURIAN SEA Montenegro Strait Pelagos Sanctuary Gulf of Italy Lion ADRIATIC SEA Albania Corsica Drini Bay Spain Dardanelles Strait Greece BALEARIC SEA Turkey Sardinia Algerian- TYRRHENIAN SEA AEGEAN SEA Balearic Islands Provençal IONIAN SEA Syria Basin Strait of Sicily Cyprus Strait of Sicily Gibraltar ALBORAN SEA Hellenic Trench Lebanon Tunisia Malta LEVANTINE SEA Israel Algeria West Morocco Bank Tunisian Plateau/Gulf of SirteMEDITERRANEAN SEA Gaza Strip Jordan Suez Canal Egypt Gulf of Sirte Libya RED SEA Marine mammals and sea turtles of the Mediterranean and Black Seas Compiled by María del Mar Otero and Michela Conigliaro The designation of geographical entities in this book, and the presentation of the material, do not imply the expression of any opinion whatsoever on the part of IUCN concerning the legal status of any country, territory, or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. The views expressed in this publication do not necessarily reflect those of IUCN. Published by Compiled by María del Mar Otero IUCN Centre for Mediterranean Cooperation, Spain © IUCN, Gland, Switzerland, and Malaga, Spain Michela Conigliaro IUCN Centre for Mediterranean Cooperation, Spain Copyright © 2012 International Union for Conservation of Nature and Natural Resources With the support of Catherine Numa IUCN Centre for Mediterranean Cooperation, Spain Annabelle Cuttelod IUCN Species Programme, United Kingdom Reproduction of this publication for educational or other non-commercial purposes is authorized without prior written permission from the copyright holder provided the sources are fully acknowledged. -
The History of Ice on Earth by Michael Marshall
The history of ice on Earth By Michael Marshall Primitive humans, clad in animal skins, trekking across vast expanses of ice in a desperate search to find food. That’s the image that comes to mind when most of us think about an ice age. But in fact there have been many ice ages, most of them long before humans made their first appearance. And the familiar picture of an ice age is of a comparatively mild one: others were so severe that the entire Earth froze over, for tens or even hundreds of millions of years. In fact, the planet seems to have three main settings: “greenhouse”, when tropical temperatures extend to the polesand there are no ice sheets at all; “icehouse”, when there is some permanent ice, although its extent varies greatly; and “snowball”, in which the planet’s entire surface is frozen over. Why the ice periodically advances – and why it retreats again – is a mystery that glaciologists have only just started to unravel. Here’s our recap of all the back and forth they’re trying to explain. Snowball Earth 2.4 to 2.1 billion years ago The Huronian glaciation is the oldest ice age we know about. The Earth was just over 2 billion years old, and home only to unicellular life-forms. The early stages of the Huronian, from 2.4 to 2.3 billion years ago, seem to have been particularly severe, with the entire planet frozen over in the first “snowball Earth”. This may have been triggered by a 250-million-year lull in volcanic activity, which would have meant less carbon dioxide being pumped into the atmosphere, and a reduced greenhouse effect. -
DEEP SEA LEBANON RESULTS of the 2016 EXPEDITION EXPLORING SUBMARINE CANYONS Towards Deep-Sea Conservation in Lebanon Project
DEEP SEA LEBANON RESULTS OF THE 2016 EXPEDITION EXPLORING SUBMARINE CANYONS Towards Deep-Sea Conservation in Lebanon Project March 2018 DEEP SEA LEBANON RESULTS OF THE 2016 EXPEDITION EXPLORING SUBMARINE CANYONS Towards Deep-Sea Conservation in Lebanon Project Citation: Aguilar, R., García, S., Perry, A.L., Alvarez, H., Blanco, J., Bitar, G. 2018. 2016 Deep-sea Lebanon Expedition: Exploring Submarine Canyons. Oceana, Madrid. 94 p. DOI: 10.31230/osf.io/34cb9 Based on an official request from Lebanon’s Ministry of Environment back in 2013, Oceana has planned and carried out an expedition to survey Lebanese deep-sea canyons and escarpments. Cover: Cerianthus membranaceus © OCEANA All photos are © OCEANA Index 06 Introduction 11 Methods 16 Results 44 Areas 12 Rov surveys 16 Habitat types 44 Tarablus/Batroun 14 Infaunal surveys 16 Coralligenous habitat 44 Jounieh 14 Oceanographic and rhodolith/maërl 45 St. George beds measurements 46 Beirut 19 Sandy bottoms 15 Data analyses 46 Sayniq 15 Collaborations 20 Sandy-muddy bottoms 20 Rocky bottoms 22 Canyon heads 22 Bathyal muds 24 Species 27 Fishes 29 Crustaceans 30 Echinoderms 31 Cnidarians 36 Sponges 38 Molluscs 40 Bryozoans 40 Brachiopods 42 Tunicates 42 Annelids 42 Foraminifera 42 Algae | Deep sea Lebanon OCEANA 47 Human 50 Discussion and 68 Annex 1 85 Annex 2 impacts conclusions 68 Table A1. List of 85 Methodology for 47 Marine litter 51 Main expedition species identified assesing relative 49 Fisheries findings 84 Table A2. List conservation interest of 49 Other observations 52 Key community of threatened types and their species identified survey areas ecological importanc 84 Figure A1. -
Alborán Sea IMMA
Alborán Sea Important Marine Mammal Area - IMMA Description Criterion A – Species or Population Vulnerability Area Size The common dolphin Mediterranean 55,939 km 2 subpopulation is listed as Endangered in the IUCN Red List of Threatened Species. This area Qualifying Species and Criteria has the largest concentration of the common Common dolphin - Delphinus delphis dolphin subpopulation within the whole Criterion A; B (ii); C (i, ii); D (i) Mediterranean, containing the large majority Common bottlenose dolphin - of the total population, both due to large Tursiops truncatus density of groups and due to very large group Criterion A; B (ii); C (i, ii); D (i) sizes, much larger than anywhere else in the Mediterranean. The most recent abundance Marine Mammal Diversity estimate of common dolphin is of 19,082 Criterion D (ii) (CV=4.7%) animals only in the northern third [Balaenoptera physalus, Globicephala melas, Orcinus orca, Grampus griseus, of the Alborán Sea with an extension to Physeter macrocephalus, Ziphius cavirostris, include the Alborán island. Stenella coeruleoalba ] The common bottlenose dolphin Summary Mediterranean subpopulation is listed as The Alborán Sea, the westernmost part of Vulnerable in the IUCN Red List of Threatened the Mediterranean Sea, opens to the Species. The Alborán Sea also has large Atlantic Ocean through the Strait of concentrations of bottlenose dolphins, which Gibraltar, becoming a transition area between these two basins which have also present some of the largest group sizes in radically different oceanographic the Mediterranean. The latest estimate of characteristics. This transition area contains abundance of bottlenose dolphin in the important habitat for Endangered northern third of the Alborán Sea with an Mediterranean common dolphins extension to include the Alborán island is (Delphinus delphis ) and Vulnerable common 2,150 animals (CV=24.3). -
Late Pleistocene Climate Change and Its Impact on Palaeogeography of the Southern Baltic Sea Region
Late Pleistocene climate change and its impact on palaeogeography of the southern Baltic Sea region Leszek Marks Polish Geological Institute–National Research Institute, Warsaw, Poland Department of Climate Geology, University of Warsaw, Warsaw, Poland Main items • Regional bakground for climatic impact of the Eemian sea • Outline of Eemian climate changes in the adjoining terrestrial area • Principles of Central European climate during the last glacial stage • Climate change at the turn of Pleistocene and Holocene Surface hydrography of the Baltic Sea PRESENT EEMIAN SALINITY OF SURFACE WATER: dark blue – >30‰, light blue – 25-30‰, brown – 15-25‰, yellow – 5-15‰, red – <5‰ CURRENTS INDICATED BY ARROWS: red – warm surface current, blue – cold bottom current, green – brackish surface current (≈10‰), stripped red/yellow – coastal water surface current (>15‰), yellow – major source of river runoff Funder 2002) Eemian sea in the Lower Vistula Valley Region Cierpięta research borehole Cierpięta Makowska (1986), modified Chronology of Eemian based on pollen stratigraphy RPAZ after Mamakowa (1988, 1989) Head et al. (2005) Correlation of Eemian LPAZ with RPAZ in southern Baltic region Knudsen et al. (2012) Chronology of Eemian sea in southern Baltic region Top of Eemian deposits ca. 8500–11 000 yrs Boundary E5/E6 7000 lat Top of marine Eemian deposits Boundary E4/E5 3000 yrs Boundary E3/E4 750 yrs Boundary E2/E3 300 yrs E1 or E2 <300 yrs Bottom of marine Eemian deposits Boundary Saalian/Eemian 0 (126 ka BP) Based on correlation with regional pollen -
Geomorphological Signature of Late Pleistocene Sea Level Oscillations in Torre Guaceto Marine Protected Area (Adriatic Sea, SE Italy)
water Article Geomorphological Signature of Late Pleistocene Sea Level Oscillations in Torre Guaceto Marine Protected Area (Adriatic Sea, SE Italy) Francesco De Giosa 1, Giovanni Scardino 2 , Matteo Vacchi 3,4 , Arcangelo Piscitelli 1, Maurilio Milella 1, Alessandro Ciccolella 5 and Giuseppe Mastronuzzi 2,* 1 Environmental Surveys Srl, Via Dario Lupo 65, 74121 Taranto, Italy; [email protected] (F.D.G.); [email protected] (A.P.); [email protected] (M.M.) 2 Dipartimento di Scienze della Terra e Geoambientali, Università degli Studi di Bari “Aldo Moro”, Via Edoardo Orabona 4, 70125 Bari, Italy; [email protected] 3 Dipartimento di Scienze della Terra, Università di Pisa, Via Santa Maria 53, 56126 Pisa, Italy; [email protected] 4 CIRSEC, Center for Climate Change Impact, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy 5 Consorzio di Gestione di Torre Guaceto, Via Sant’Anna 6, 72012 Carovigno (Brindisi), Italy; [email protected] * Correspondence: [email protected] Received: 10 September 2019; Accepted: 12 November 2019; Published: 16 November 2019 Abstract: Morphostratigraphy is a useful tool to reconstruct the sequence of processes responsible for shaping the landscape. In marine and coastal areas, where landforms are only seldom directly recognizable given the difficulty to have eyewitness of sea-floor features, it is possible to correlate geomorphological data derived from indirect surveys (marine geophysics and remote sensing) with data obtained from direct ones performed on-land or by scuba divers. In this paper, remote sensing techniques and spectral images allowed high-resolution reconstruction of both morpho-topography and morpho-bathymetry of the Torre Guaceto Marine Protected Area (Italy). -
A Possible Late Pleistocene Impact Crater in Central North America and Its Relation to the Younger Dryas Stadial
A POSSIBLE LATE PLEISTOCENE IMPACT CRATER IN CENTRAL NORTH AMERICA AND ITS RELATION TO THE YOUNGER DRYAS STADIAL SUBMITTED TO THE FACULTY OF THE UNIVERSITY OF MINNESOTA BY David Tovar Rodriguez IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE Howard Mooers, Advisor August 2020 2020 David Tovar All Rights Reserved ACKNOWLEDGEMENTS I would like to thank my advisor Dr. Howard Mooers for his permanent support, my family, and my friends. i Abstract The causes that started the Younger Dryas (YD) event remain hotly debated. Studies indicate that the drainage of Lake Agassiz into the North Atlantic Ocean and south through the Mississippi River caused a considerable change in oceanic thermal currents, thus producing a decrease in global temperature. Other studies indicate that perhaps the impact of an extraterrestrial body (asteroid fragment) could have impacted the Earth 12.9 ky BP ago, triggering a series of events that caused global temperature drop. The presence of high concentrations of iridium, charcoal, fullerenes, and molten glass, considered by-products of extraterrestrial impacts, have been reported in sediments of the same age; however, there is no impact structure identified so far. In this work, the Roseau structure's geomorphological features are analyzed in detail to determine if impacted layers with plastic deformation located between hard rocks and a thin layer of water might explain the particular shape of the studied structure. Geophysical data of the study area do not show gravimetric anomalies related to a possible impact structure. One hypothesis developed on this works is related to the structure's shape might be explained by atmospheric explosions dynamics due to the disintegration of material when it comes into contact with the atmosphere. -
Greenland Climate Simulations Show High Eemian Surface Melt Which Could Explain Reduced Total Air Content in Ice Cores
Clim. Past, 17, 317–330, 2021 https://doi.org/10.5194/cp-17-317-2021 © Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. Greenland climate simulations show high Eemian surface melt which could explain reduced total air content in ice cores Andreas Plach1,2,3, Bo M. Vinther4, Kerim H. Nisancioglu1,5, Sindhu Vudayagiri4, and Thomas Blunier4 1Department of Earth Science, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway 2Department of Meteorology and Geophysics, University of Vienna, Vienna, Austria 3Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland 4Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark 5Centre for Earth Evolution and Dynamics, University of Oslo, Oslo, Norway Correspondence: Andreas Plach ([email protected]) Received: 27 July 2020 – Discussion started: 18 August 2020 Revised: 27 November 2020 – Accepted: 1 December 2020 – Published: 29 January 2021 Abstract. This study presents simulations of Greenland sur- 1 Introduction face melt for the Eemian interglacial period (∼ 130000 to 115 000 years ago) derived from regional climate simula- tions with a coupled surface energy balance model. Surface The Eemian interglacial period (∼ 130000 to 115 000 years melt is of high relevance due to its potential effect on ice ago; hereafter ∼ 130 to 115 ka) was the last period with a core observations, e.g., lowering the preserved total air con- warmer-than-present summer climate on Greenland (CAPE tent (TAC) used to infer past surface elevation. An investi- Last Interglacial Project Members, 2006; Otto-Bliesner et al., gation of surface melt is particularly interesting for warm 2013; Capron et al., 2014).