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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. -
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. -
A New Greenland Ice Core Chronology for the Last Glacial Termination ———————————————————————— S
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. ???, XXXX, DOI:10.1029/2005JD006079, A new Greenland ice core chronology for the last glacial termination ———————————————————————— S. O. Rasmussen1, K. K. Andersen1, A. M. Svensson1, J. P. Steffensen1, B. M. Vinther1, H. B. Clausen1, M.-L. Siggaard-Andersen1,2, S. J. Johnsen1, L. B. Larsen1, D. Dahl-Jensen1, M. Bigler1,3, R. R¨othlisberger3,4, H. Fischer2, K. Goto-Azuma5, M. E. Hansson6, and U. Ruth2 Abstract. We present a new common stratigraphic time scale for the NGRIP and GRIP ice cores. The time scale covers the period 7.9–14.8 ka before present, and includes the Bølling, Allerød, Younger Dryas, and Early Holocene periods. We use a combination of new and previously published data, the most prominent being new high resolution Con- tinuous Flow Analysis (CFA) impurity records from the NGRIP ice core. Several inves- tigators have identified and counted annual layers using a multi-parameter approach, and the maximum counting error is estimated to be up to 2% in the Holocene part and about 3% for the older parts. These counting error estimates reflect the number of annual lay- ers that were hard to interpret, but not a possible bias in the set of rules used for an- nual layer identification. As the GRIP and NGRIP ice cores are not optimal for annual layer counting in the middle and late Holocene, the time scale is tied to a prominent vol- canic event inside the 8.2 ka cold event, recently dated in the DYE-3 ice core to 8236 years before A.D. -
Gabriola's Glacial Drift—An Icecap?
Context: Gabriola ice-age geology Citation: Doe, N.A., Gabriola’s glacial drift—10. An icecap? SILT 8-10, 2014. <www.nickdoe.ca/pdfs/Webp530.pdf>. Accessed 2014 Jan 30. NOTE: Adjust the accessed date as needed. Copyright restrictions: Copyright © 2014. Not for commercial use without permission. Date posted: January 30, 2014. Author: Nick Doe, 1787 El Verano Drive, Gabriola, BC, Canada V0R 1X6 Phone: 250-247-7858 E-mail: [email protected] This is Version 3.7, the final version. Notes added on June 9, 2021: There is an error in the caption to the graph on page 15. The yellow dot on the left is for plant material, the older one on the right is for a log. It has been left uncorrected in this copy. Additional radiocarbon dates have been obtained since this article was published and these are recorded in detail in Addendum 2021 to SILT 8-13 <https://nickdoe.ca/pdfs/Webp533.pdf>. The new information affects some of the detail in this Version 3.7, particularly on page 15, but not significantly enough to justify an extensive rewrite and republishing of the article. Version 3.7 therefore remains unchanged. Version:3.7 Gabriola’s glacial drift—an icecap? Nick Doe Carlson, A. E. (2011) Ice Sheets and Sea Level in Earth’s Past. Nature Education Knowledge 3(10):3 The deglaciation of Gabriola what ways did the events of that time shape the landscape we see today? One snowy winter’s day, around the year 14 The two approaches adopted are radiocarbon 16000 BC (14.50 ka C BP), give or take a dating of sites that mark the transition from century or two, the ice under which Gabriola the late-Pleistocene to the early-Holocene was buried at that time, reached its 1 (ice age to post-ice age); and computer maximum thickness. -
Alphabetical List
LIST E - GEOLOGIC AGE (STRATIGRAPHIC) TERMS - ALPHABETICAL LIST Age Unit Broader Term Age Unit Broader Term Aalenian Middle Jurassic Brunhes Chron upper Quaternary Acadian Cambrian Bull Lake Glaciation upper Quaternary Acheulian Paleolithic Bunter Lower Triassic Adelaidean Proterozoic Burdigalian lower Miocene Aeronian Llandovery Calabrian lower Pleistocene Aftonian lower Pleistocene Callovian Middle Jurassic Akchagylian upper Pliocene Calymmian Mesoproterozoic Albian Lower Cretaceous Cambrian Paleozoic Aldanian Lower Cambrian Campanian Upper Cretaceous Alexandrian Lower Silurian Capitanian Guadalupian Algonkian Proterozoic Caradocian Upper Ordovician Allerod upper Weichselian Carboniferous Paleozoic Altonian lower Miocene Carixian Lower Jurassic Ancylus Lake lower Holocene Carnian Upper Triassic Anglian Quaternary Carpentarian Paleoproterozoic Anisian Middle Triassic Castlecliffian Pleistocene Aphebian Paleoproterozoic Cayugan Upper Silurian Aptian Lower Cretaceous Cenomanian Upper Cretaceous Aquitanian lower Miocene *Cenozoic Aragonian Miocene Central Polish Glaciation Pleistocene Archean Precambrian Chadronian upper Eocene Arenigian Lower Ordovician Chalcolithic Cenozoic Argovian Upper Jurassic Champlainian Middle Ordovician Arikareean Tertiary Changhsingian Lopingian Ariyalur Stage Upper Cretaceous Chattian upper Oligocene Artinskian Cisuralian Chazyan Middle Ordovician Asbian Lower Carboniferous Chesterian Upper Mississippian Ashgillian Upper Ordovician Cimmerian Pliocene Asselian Cisuralian Cincinnatian Upper Ordovician Astian upper -
Major AC Excursions During the Late Glacial and Early Holocene
Quaternary International 105 (2003) 71–76 Major D14C excursions during the late glacial and early Holocene: changes in ocean ventilation or solar forcing of climate change? Bas van Geela,*, Johannes van der Plichtb, Hans Renssenc a Institute for Biodiversity and Ecosystem Dynamics, Universiteit van Amsterdam, Kruislaan 318, 1098 SM Amsterdam, The Netherlands b Centre for Isotope Research, Rijksuniversiteit Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands c Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands We dedicate this paper to Thomas van der Hammen, one of the pioneers in the study of climate change during the Late Glacial period Abstract The atmospheric 14C record during the Late Glacial and the early Holocene shows sharp increases simultaneous with cold climatic 14 phases. These increases in the atmospheric C content are usually explained as the effect of reduced oceanic CO2 ventilation after episodic outbursts of large meltwater reservoirs into the North Atlantic. In this hypothesis the stagnation of the thermohaline circulation is the cause of both climate change as well as an increase in atmospheric 14C: As an alternative hypothesis we propose that changes in 14C production give an indication for the cause of the recorded climate shifts: changes in solar activity cause fluctuations in the solar wind, which modulate the cosmic ray intensity and related 14C production. Two possible mechanisms amplifying the changes in solar activity may result in climate change. In the case of a temporary decline in solar activity: (1) reduced solar UV intensity may cause a decline of stratospheric ozone production and cooling as a result of less absorption of sunlight. -
Paleopedogenesis During the Mikulino Interglacial (MIS 5Е) in the East-European Plain: Buried Toposequence of the Key-Section “Alexandrov Quarry”
Paleopedogenesis during MIS 5e in the East-European plain 189 BOLETÍN DE LA SOCIEDAD GEOLÓGICA MEXICANA VOLUMEN 64, NÚM. 2, 2012, P. 189-197 D GEOL DA Ó E G I I C C O A S 1904 M 2004 . C EX . ICANA A C i e n A ñ o s Paleopedogenesis during the Mikulino interglacial (MIS 5е) in the East-European plain: buried toposequence of the key-section “Alexandrov quarry” Svetlana Sycheva1, Sergey Sedov2,* 1 Institute of Geography, RAS. Staromonetny 29, Moscow, 119017, Russia 2 Instituto de Geología, Universidad Nacional Autónoma de México, México * [email protected] Abstract The Alexandrovsky quarry exposure (near Kursk, central European Russia) represents one of the most complete and detailed records of paleosols, colluvial sediments and loess for the last glacial-interglacial cycle in Eastern Europe. The buried toposequence of Mikulino (Eemian) paleosols, developed on a gully slope cut in the Dnepr (Riss) loess and overlain by Early Valdai (Würmian) colluvium, was subjected to detailed morphological study. The paleosol on the upper slope is an Albeluvisol that contrasts from the Holocene Cherno- zem. Analysis of thin sections of the Albeluvisol demonstrated that elluvial features – concentrations of bleached silt in the pores and in the groundmass – dominate not only in E and EB but also in the Bt1 horizon. They also penetrate into lower Bt2 and Bt3 horizons where they combine with illuvial clay pedofeatures. The paleosol profile at the bottom of the gully shows synsedimentary development with several A, AE and E horizons reflecting several phases of geomorphic activity as a response to a complex environmental history during the last interglacial. -
Vegetation Responses to Climatic Changes During the Late Glacial According to Palaeobotanical Data in Western Lithuania; a Preliminary Results
Polish Geological Institute Special Papers, 16 (2005): 45–52 Proceedings of the Workshop “Reconstruction of Quaternary palaeoclimate and palaeoenvironments and their abrupt changes” VEGETATION RESPONSES TO CLIMATIC CHANGES DURING THE LATE GLACIAL ACCORDING TO PALAEOBOTANICAL DATA IN WESTERN LITHUANIA; A PRELIMINARY RESULTS Dalia KISIELIENE1, Migle STANCIKAITE1, Algimantas MERKEVICIUS2, Reda NAMICKIENE2 Abstract. The organic-rich material has been studied from the bottom part of lacustrine sediments of the Lake Kasuciai, west- ern Lithuania. Radiocarbon dates and palaeobotanical data showed that these sediments accumulated between 13,500 and 9000 14C yr BP. The Late Glacial interstadial is defined by the dominance of Characeae and accumulation of carbonate. The Bølling is characterized by the pioneer taxa and the communities of open habitats. During the Allerød pine replaced the light demanding taxa that show development of a closer woodland habitat and dryness of climate. The short period be- tween Bølling and Allerød with increasing representation of Betula and plants typical for the highly eroded habitats could be correlated with Older Dryas. The onset of the Younger Dryas is marked by degradation of the forest cover and expansion of heliophytic grasses. Entire vegetation cover with birch and pine forest was settled during the Preborial. Formation of cal- careous sediments and appearance of thermophilous taxa confirm the climatic amelioration. Key words: environmental changes, pollen and plant macroremains, Late Glacial, western Lithuania. INTRODUCTION In Lithuania the rich data set describing the main features of ecological regime of this area since the 14,000 14C uncalibrated the Younger Dryas and Allerød environment was collected af- BP and until the end of the last termination. -
Implications for the Older Dryas Glacial Re-Advance and the Age of the Deglaciation
bs_bs_banner The Bølling-age Blomvag Beds, western Norway: implications for the Older Dryas glacial re-advance and the age of the deglaciation JAN MANGERUD, JASON P. BRINER, TOMASZ GOSLAR AND JOHN INGE SVENDSEN Mangerud, J., Briner, J. P., Goslar, T. & Svendsen, J. I. 2017 (April): The Bølling-age Blomvag Beds, western Norway: implications for the Older Dryas glacial re-advance and the age of the deglaciation. Boreas, Vol. 46, pp. 162–184. 10.1111/bor.12208. ISSN 0300-9483. Blomvag, on the western coast of Norway north of Bergen, is a classical site in Norwegian Quaternary science. Foreshore marine sediments, named the Blomvag Beds and now dated to the Bølling-Allerød from 14.8 to 13.3 cal. ka BP, contain the richest Lateglacial bone fauna in Norway, numerous mollusc shells, driftwood, and flint that some archaeologists consider as the oldest traces of humans in Norway. The main theme of this paper is that the Blomvag Beds are overlain by a compact diamicton, named the Ulvøy Diamicton, which was interpreted previously as a basal till deposited during a glacial re-advance into the ocean during the Older Dryas (c. 14 cal. ka BP). Sediment sections of the Blomvag Beds and the Ulvøy Diamicton were exposed in ditches in a cemetery that was constructed in 1941–42 and have subsequently not been accessible. A number of radiocarbon and cosmo- genic 10Be exposure ages demonstrate that the diamicton is not likely to be a till because minimum deglaciation ages (14.8–14.5 cal. ka BP) from the vicinity pre-date the Ulvøy Diamicton. -
Article Is financed by CNRS-INSU
Clim. Past, 5, 615–632, 2009 www.clim-past.net/5/615/2009/ Climate © Author(s) 2009. This work is distributed under of the Past the Creative Commons Attribution 3.0 License. Terrestrial climate variability and seasonality changes in the Mediterranean region between 15 000 and 4000 years BP deduced from marine pollen records I. Dormoy1,2, O. Peyron1, N. Combourieu Nebout2, S. Goring3, U. Kotthoff4,5, M. Magny1, and J. Pross4 1Laboratory of Chrono-Environnement, UMR CNRS 6249, University of Franche-Comte,´ 16 route de Gray, 25030 Besanc¸on, France 2Laboratory of Sciences of Climate and Environment, UMR 1572 CEA-CNRS-UVSQ, domaine du CNRS, avenue de la Terrasse, 91198 Gif-sur-Yvette, France 3Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, V5A 1S6, Canada 4Institute of Geosciences, University of Frankfurt, Altenhoferallee¨ 1, 60438 Frankfurt, Germany 5Department of Geosciences, Hamburg University, Bundesstrasse 55, 20146 Hamburg, Germany Received: 26 January 2009 – Published in Clim. Past Discuss.: 27 February 2009 Revised: 14 September 2009 – Accepted: 15 September 2009 – Published: 19 October 2009 Abstract. Pollen-based climate reconstructions were per- Oscillations, 8.2 ka event, Bond events) connected to the formed on two high-resolution pollen marines cores from the North Atlantic climate system are documented in the Albo- Alboran and Aegean Seas in order to unravel the climatic ran and Aegean Sea records indicating that the climate oscil- variability in the coastal settings of the Mediterranean re- lations associated with the successive steps of the deglacia- gion between 15 000 and 4000 years BP (the Lateglacial, and tion in the North Atlantic area occurred in both the western early to mid-Holocene). -
From Oxbow to Mire: Chironomidae and Cladocera As Habitat Palaeoindicators
Hydrobiologia (2020) 847:3257–3275 https://doi.org/10.1007/s10750-020-04327-6 (0123456789().,-volV)( 0123456789().,-volV) PRIMARY RESEARCH PAPER From oxbow to mire: Chironomidae and Cladocera as habitat palaeoindicators Mateusz Pło´ciennik . Dominik Pawłowski . Lorenzo Vilizzi . Olga Antczak-Orlewska Received: 20 November 2019 / Revised: 3 June 2020 / Accepted: 9 June 2020 / Published online: 1 July 2020 Ó The Author(s) 2020 Abstract Chironomidae and Cladocera are useful European river valley of Poland. Summer air temper- palaeoindicators to describe long-term dynamics in ature and hydrological conditions were found to be the biodiversity of freshwater aquatic communities. How- main drivers of Cladocera and Chironomidae popula- ever, palaeoecological studies relying on these aquatic tions, causing a cascade effect in assemblage compo- invertebrates have generally focused on post-glacial sition. At the local habitat scale, there were lakes, with relatively few applications to floodplain autecological differences in both taxonomic groups water bodies such as palaeo-oxbow lakes. In this reflecting different responses to abiotic and biotic study, zone-level (stratigraphic) trends in Chironomi- factors. Specifically, Cladocera responded distinctly to dae and Cladocera assemblage composition were plant vegetation and fish predation during the Late analysed from a small palaeo-oxbow lake in a Central Glacial lake phase, whereas Chironomidae were more sensitive to paludification processes and disappeared in the Northgrippian dry phase of the mire. Both Handling editor: Jasmine Saros groups indicated fluvial activity of the River Grabia, M. Pło´ciennik (&) although the response was different. Also, species Department of Invertebrate Zoology and Hydrobiology, richness was higher in the more taxonomically diverse Faculty of Biology and Environmental Protection, Chironomidae compared to Cladocera. -
Last Glacial Maximum and Younger Dryas Piedmont Glaciations in Blidinje, the Dinaric Mountains (Bosnia and Herzegovina) Çiner, Attila; Stepišnik, Uroš; Sarkaya, M
Aberystwyth University Last Glacial Maximum and Younger Dryas piedmont glaciations in Blidinje, the Dinaric Mountains (Bosnia and Herzegovina) Çiner, Attila; Stepišnik, Uroš; Sarkaya, M. Akif; Zebre, Manja; Yldrm, Cengiz Published in: Mediterranean Geoscience Reviews DOI: 10.1007/s42990-019-0003-4 Publication date: 2019 Citation for published version (APA): Çiner, A., Stepišnik, U., Sarkaya, M. A., Zebre, M., & Yldrm, C. (2019). Last Glacial Maximum and Younger Dryas piedmont glaciations in Blidinje, the Dinaric Mountains (Bosnia and Herzegovina): insights from 36Cl cosmogenic dating. Mediterranean Geoscience Reviews. https://doi.org/10.1007/s42990-019-0003-4 General rights Copyright and moral rights for the publications made accessible in the Aberystwyth Research Portal (the Institutional Repository) are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the Aberystwyth Research Portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the Aberystwyth Research Portal Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. tel: +44 1970 62 2400 email: