141 research outputs found
How Britain became an island
Island Britain is separated from the European continent by the English Channel and the North Sea. But it was not always so. The floor of the Channel provides evidence for two catastrophic floods arising from the drainage of huge glacial lakes in the area of the southern North Sea. These megafloods carved the Dover Strait to make Britain the island it is today
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Human occupation of northern Europe in MIS 13: Happisburgh Site 1 (Norfolk, UK) and its European context: a response to Lewis et al. (2019)
This comment concerns the article by Lewis et al. (2019). We do not question the detail of the
Happisburgh site sequence, but the stratigraphical significance, the regional correlations and the age of
certain localities with which the Happisburgh 1 sequence is equated by these authors. In particular we
question the correlation with sequences at Warren Hill and High Lodge in Suffolk since detailed research
has demonstrated that they are neither the same age nor of the origin stated in the original article. We also
question the correlation of disparate geological sequences on the basis of their artefactual contents; an
approach long considered to be inappropriate
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Global chronostratigraphical correlation table for the last 2.7 million years, version 2019 QI-500
A substantially updated version of the correlation table showing chronostratigraphical subdivisions of late Cenozoic geological time, spanning the last 2.7 million years is presented. It provides scientists, students, professionals and the general public with a ready reference to stratigraphical terms and schemes in use in different areas for similar periods. The updates comprised the status of Quaternary chronostratigraphic subdivision, the combined age-modelled geomagnetic and isotope records from ocean drilling records, and revised regional correlation schemes, notably for eastern Europe. The paper describes the chart in its 2019 QI-500 form and contains sections on its types of usage and formal subdivision status, besides reference and description of the contents of the various columns. The paper also describes and discusses the resolution of correlations in younger and older parts of the last 2.7 Ma.n/
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The “Missing Glaciations” of the Middle Pleistocene
Global glaciations have varied in size and magnitude since the Early-Middle Pleistocene transition (~773 ka), despite the apparent regular and high-amplitude 100 kyr pacing of glacial-interglacial cycles recorded in marine isotopic records. The evidence on land indicates that patterns of glaciation varied dramatically between different glacial-interglacial cycles. For example, MIS (Marine Isotope Stages) 8, 10 and 14 are all noticeably absent from many terrestrial glacial records in North America and Europe. However, globally, the patterns are more complicated with major glaciations recorded in MIS 8 in Asia and in parts of the Southern Hemisphere, such as Patagonia for example. This spatial variability in glaciation between glacial-interglacial cycles is likely to be driven by ice volume changes in the West Antarctic Ice Sheet and associated interhemispheric connections through ocean-atmosphere circulatory changes. The weak global glacial imprint in some glacial-interglacial cycles is related to the pattern of global ice build-up. This is caused by feedback mechanisms within glacier systems themselves which partly result from long-term orbital changes driven by eccentricity.n/
IUGS ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma
The International Union for Geological Sciences (IUGS) on 29 June, 2009 ratified a proposal by the International Commission on Stratigraphy that the base of the Quaternary System/Period and the base of the Pleistocene Series/Epoch be lowered to that of the Gelasian Stage/Age. The Gelasian is transferred accordingly from the Pliocene to the Pleistocene. The Global Stratotype Section and Point at Monte San Nicola, Sicily, Italy, with an estimated age of 2.58 Ma, defines the lower boundary of the Gelasian, Pleistocene and Quaternary. Details of the ratification are given, and implications discussed.L’Union Internationale des Sciences géologiques (IUGS) a ratifié le 29 Juin 2009 la proposition faite par la Commission Internationale de Stratigraphie (ICS) de descendre la base du Quaternaire en tant que Système/Période et celle du Pléistocène en tant que Série/Epoque pour la faire coïncider avec celle de l’Etage/Age Gélasien. En conséquence, le Gélasien est transféré du Pliocène dans le Pléistocène. La coupe et le point de référence du stratotype global (GSSP) de Monte San Nicola, en Sicile, Italie, avec un âge estimé à 2,58 Ma, définit la limite inférieure du Gélasien, du Pléistocène et du Quaternaire. Les détails de la ratification sont donnés et les implications discutées
Elsterzeitliche (Anglian) Eisdynamik in East Anglia
Gefügeuntersuchungen in Aufschlüssen in East Anglia haben gezeigt, daß während der Elster-Vereisung (Anglian) ein Eisvorstoß aus dem Nordseebecken von einem Vorstoß britischen Eises erst aus westlicher, später aus nördlicher Richtung gefolgt wurde. Durch das ungleichzeitige Vorstoßen und Abschmelzen der beiden Eisschilde und durch die isostatische Absenkung im Nordsee-Bereich hat sich zeitweise eine nach NE gerichtete Eisbewegung ergeben.researc
Rediscovery and stratigraphic calibration of the classic Nihewan Fauna, Hebei Province, China
The classic Nihewan Fauna, as the representative of early Pleistocene Asian Land Mammal Age Nihewanian, has long been cited for bio- and chronostratigraphic correlation. However, its precise provenance and stratigraphic horizon have remained unsolved till now. The authors successfully extracted the vital information by rediscovering 30 of the original excavation localities. The fossils were catalogued with their provenance through an extensive field survey and comprehensive inspection of the Tianjin Natural History Museum collection. A review of the original description of these fossil localities, using satellite images, and subsequent lithological examination of the Xiashagou strata in the field verified the new findings. The survey produced the first stratigraphic profile calibrated with fossil horizons of the Nihewan formation in the Xiashagou section. Correlated with the published magnetostratigraphical profile of the section, an age of similar to 2.4-1.8 Ma is estimated for the classic Nihewan Fauna.Peer reviewe
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