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Weichselian Glacial History of Finland Herzen State Pedagogical
Weichselian glacial history of Finland Herzen State Pedagogical University, Department of Geography. St. Petersburg 19.-20.02.2019 Peter Johansson Rovaniemi Helsinki St. Petersburg Granulite Complex 1900 Ma Pre-svecokarelidic base complex 2700 – 2800 Ma Svekokarelides 1800 - 1930 Postsvekokarelidian igneous rocks, rapa- kivi 1540 – 1650 Ma Postsvekokarelidian sedimentary rocks, 1200 – 1400 Ma Caledonides 400 – 450 Ma The zone of weathered bedrock in Finland Investigations of Quaternary stratigraphy Percussion drilling machine with hydraulic piston corer. Sokli investigation area. In the Kemijoki River valley there are often more than one till unit commonly found. They are interbedded with sediment and organic layers (K. Korpela 1969). Permantokoski hydroelectric power station (1) was the key area of the till investigations in 1960’s. RUSSIA In 1970’ s more than 1300 test pits were made by tractor excavator. In numerous sites more than two till beds inter- bedded with stratified sediments occur. (Hirvas et al. 1977 and Hirvas 1991) Moreenipatja II Moreenipatja IV Hiekka Kivien Moreenipatja III Glasfluv. hiekka suuntaus (Johansson & Kujansuu 2005) Older till Younger till Till III Till II Ice-flow directions Deglaciation phase Late Weichselian Middle Weichselian Saalian Unknown Ice divide zone More than 100 observations of subtill organic deposits have been made in Northern Finland. Fifty deposits have been studied: 39 = interglacial, 10 = interstadial and one both. In the picture stratigraphic positions of the interglacial deposits and correlation of the general till stratigraphy of northern Finland. (H. Hirvas 1991) (H. Hirvas 1991) Seeds of Aracites interglacialis (Aalto, Eriksson and Hirvas 1992) The Rautuvaara section in western Lapland has been considered as a type section for the northern Fennoscandian Middle and Late Pleistocene. -
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. -
Provenance of Early Pleistocene Sediments Based on a High-Resolution Sedimentological Dataset of Borehole Petten, Southern North Sea
Provenance of Early Pleistocene sediments based on a high-resolution sedimentological dataset of borehole Petten, southern North Sea Hao Ding 6559972 A thesis submitted for the degree of MSc Earth, Life and Climate Utrecht University July, 2020 1 Preface and Acknowledgements This thesis was written as part of the Master of Science degree in Earth Sciences, program Earth, Life and Climate, at Utrecht University. The research was performed under the supervision of Kim Cohen and Wim Hoek, also with help of Timme Donders and Alexander Houben. This research, together with a parallel research conducted by Lissane Krom, contributes to a larger project in paleoenvironment reconstruction of the Early Pleistocene in the southern North Sea Basin, based on the Petten Borehole 1. This thesis focused on sedimentology, and the parallel thesis by Krom focused on palynology. For the process of this project, I would like to express my gratitude to my supervisors Kim Cohen and Wim Hoek for their great effort on the research and lab work guidance. All the redactional and scientific comments on my writing from Kim Cohen are highly appreciated. I would also like to thank Timme Donders, Alexander Houben and Lisanne Krom for all the cross-disciplinary discussions as well as the assistance on my final presentation. Last but not least, I would like to thank my family and friends, who have been supporting me as always during this Covid-19 pandemic. Studying abroad has been tough, but I really appreciate all the love and encouragement around me, no matter how far apart we are. 2 Abstract In 2018, a fairly complete core (Petten BH 1) reaching over 300 meters into the unconsolidated, dominantly sandy Pleistocene sequence was recovered in the northwest of the Netherlands, in the coastal dune area along the present North Sea. -
Late Quaternary Evolution of the Western Nordenskiold Land
POLISH POLAR RESEARCH 14 3 259-274 1993 Andrzej MUSIAŁ, Bogdan HORODYSKI and Krzysztof KOSSOBUDZKI Department of Geography and Regional Studies Warsaw University Krakowskie Przedmieście 30 00-927 Warszawa, POLAND Late Quaternary evolution of the western Nordenskiold Land ABSTRACT: Relief of Svalbard is an effect of varied morphogenetic, exogenic and endogenic processes. Tectonic and glacioisostatic movements of the Earth crust have occurred many a time in this region. Glacial, marine and periglacial features are particularly common. During the Late Quaternary the western Nordenskiold Land underwent several sea transgressions, followed by glacier advances. Basing on erratics of crystalline rocks transported by sea ice, past sea levels have been established up to 250 m a.s.l. Marine terraces above 60 m a.s.l. date back to the Late Pleistocene, the lower ones are of the Holocene age. Key words: Arctic, Spitsbergen, Quaternary evolution. The western Nordenskiold Land between Bellsund, Greenland Sea, Isfjorden and Gronfjorden is a highly diversified area if its geology and landscape are concerned (Musiał 1983, 1984, 1985, Musiał et al. 1990). The paper presents research on landscape evolution in polar conditions which has been carried out in western Spitsbergen by academic expeditions organized by the Department of Geography and Regional Studies of the Warsaw University in 1978, 1980, 1985 and 1988. Seaside plains of Vast Langnes, Isfjorden and Vardeborg stretch westwards into an abrasive platform in which there are lowerings, consistent with the present fiords (Fig. 1). The plains are delimited in the east by two parallel mountain massifs with prominent peaks of Griegfjellet (778 m), Systemafjellet (744 m), Ytterdalsgubben (901 m), Ytterdalssata (593 m), Vardeborg (588 m), Qvigstad- fjellet (770 m), Foldtinden (730 m) and Flynibba (745 m a.s.l.). -
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. -
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 -
The Uppsala Esker: the Asby-~Ralinge Exposures
The Uppsala Esker: The Asby-~ralingeExposures ERLING LINDSTR~M Lindstrbm, E., 1985 02 01: TheUppsalaEsker: The Asby-~rain~eExposures.-In Glacio- nigsson, Ed.). Striae, Vol. 22, pp. 27-32. Uppsala. ISBN 91-7388-044-2. Detailed field studies of two exposures of the Uppsala esker support the model of subglacial esker formation. Dr. E. Lindstriim, Uppsala university, Department of Physical Geography. Box 554, S-75122 Uppsala, Sweden. Among theories of esker formation three models are con- ~t Asby theesker broadens. Thecrest of the esker is rather sidered classic: level from here to the north with a relative height- of about 35 m. Its height a.s.1. is 62.8 mas compared to the highest 1. Subglacial formation in tunnels at the bottom of the shore line in this area (the Yoldia Sea) which is ca 160 m ice (Strandmark 1885, Olsson 1965, cf. Lindstrom 1973). and the highest limits of both the Ancylus Lake ca 100 m 2. Subaerial formation in open channels in the ice (Holst and the Littorina Sea ca 60 m (Lundeghdh-Lundqvist 1876, Tanner 1928). 1956, p. 90). The esker is modified by subsequent wave 3. Submarginal deltaic formation at the mouths of ice action resulting in the development of shore terraces on tunnels @e Geer 1897). different levels. The esker is surrounded by clay deposits This article will describe and discuss esker sedimentation covered by wavewashed fine sand and sand. as exposed in two sections of the Uppsala esker at Asby- The Asby exposure is composed of two stratigraphic Drtilinge in a subaquatic environment. -
Unit 7 Cenozoic Era with Special Reference to Quaternary Period
UNIT 7 CENOZOIC ERA WITH SPECIAL REFERENCE TO QUATERNARY PERIOD Contents 7.0 Introduction 7.1 Position of Cenozoic in the Geologic Time Scale 7.2 Chronology of Cenozoic Era 7.3 Quaternary Period and Pleistocene Glaciations 7.4 Evidences of Pleistocene Glaciations 7.5 Pluvials and Inter-pluvials 7.6 Causes of Pleistocene Glaciations 7.7 Summary 7.8 References 7.9 Answers to Check your Progress Learning Objectives Once you have studied this unit, you should be able to: Know the chronology and position of Cenozoic Era in Geological Time Scale; Understand different periods of Cenozoic Era; Study various glaciation and inter glaciation phases; and Discuss the causes of Pleistocene climatic change 7.0 INTRODUCTION The Cenozoic Era is also known as Caenozoic or Cainozoic. Cenozoic literally means ‘new life’ after the Greek roots ‘kainos’ meaning ‘new’ and ‘zoico’ meaning ‘animal life’. The Cenozoic Era is of substantial interest for anthropologists since the evolution and diversification of fossil primates, including humans, took place during this era. Besides primates, a significant portion of the evolution and radiation of various groups of mammals also happened during the Cenozoic. It is for this reason that sometimes the Cenozoic is also termed as the ‘Age of Mammals’ who were the dominant animal life of earth during the Cenozoic Era. The era began about 65 million years ago and continues into the present. The existing locations of the continents and the distribution of current flora and fauna acquired its present-day configuration during this time period. The era began at the end of Cretaceous, the last phase of the Mesozoic. -
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. -
13. Late Pliocene-Pleistocene Glaciation
13. LATE PLIOCENE - PLEISTOCENE GLACIATION W. A. Berggren, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts The discussion in this chapter is broken down into two increase in the former exceeding that of the latter; or parts: the first deals with glaciation in the North Atlantic as (v) less detritals, clay and carbonate deposited per unit time revealed in the data obtained on Leg 12; in the second part (that is, decreased sedimentation rate) with the decrease in an attempt is made to provide a chronologic framework of the latter exceeding the former. In view of the demon- Late Pliocene-Pleistocene glaciation and to correlate gla- strable increase in sedimentation rate above the preglacial/ cial/interglacial sequences as recorded in land and deep-sea glacial boundary at Sites 111, 112 and 116 due to increased sediments. amounts of detrital minerals and the fact that glacial periods in high latitudes are characterized by a carbonate GLACIATION IN THE NORTH ATLANTIC minimum (Mclntyre et al., in press) it can be seen that the One of the most significant aspects of Leg 12 was the correct explanation for the increase in natural gamma activ- various results which were obtained regarding glaciation in ity in the glacial part of the section is rather complex. Thin the North Atlantic. Glacial sediments were encountered at bands of carbonate were found at various levels intercalated all sites in the North Atlantic with the exception of Site with detrital-rich clays which indicates interglacial intervals, 117 (for the purpose of this discussion the North Atlantic so that the correct explanation probably lies with (iii) encompasses Sites 111 through 117; Sites 118 and 119 are above. -
Draft Agenda
17th ASCOBANS Advisory Committee Meeting AC17/Doc.6-08 (S) rev.2 UN Campus, Bonn, Germany, 4-6 October 2010 Dist. 06 October 2010 Agenda Item 6.1 Project Funding through ASCOBANS Progress of Supported Projects Document 6-08 rev.2 Interim Project Report: Review of Trend Analyses in the ASCOBANS Area Action Requested Take note of the report Comment Submitted by Secretariat NOTE: IN THE INTERESTS OF ECONOMY, DELEGATES ARE KINDLY REMINDED TO BRING THEIR OWN COPIES OF DOCUMENTS TO THE MEETING Secretariat’s Note Comments received by the author during the 17th Meeting of the ACOBANS Advisory Committee were incorporated in this revision. REVIEW OF CETACEAN TREND ANALYSES IN THE ASCOBANS AREA Peter G.H. Evans1, 2 1 Sea Watch Foundation, Ewyn y Don, Bull Bay, Amlwch, Isle of Anglesey LL68 9SD, Wales, UK 2 School of Ocean Sciences, University of Bangor, Menai Bridge, Isle of Anglesey LL59 5AB, Wales, UK . 1. Introduction The 16th Meeting of the Advisory Committee recommended that a review of trend analyses of stranding and other data on small cetaceans in the ASCOBANS area be carried out. The ultimate aim is to provide on an annual basis AC members with an accessible, readable and succinct overview of trends in status, distribution and impacts of small cetaceans within the ASCOBANS Agreement Area. This should combine data sets of different stakeholders and countries. 2. Terms of Reference To achieve the above aim of the project, a three-staged process was proposed: Step 1: Identify where data of interest (e.g. stranding data, but also data on