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Glacial Landscapes (glacial + landscapes)
Selected AbstractsGeoarchaeology and late glacial landscapes in the western lake superior region, Central North AmericaGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 1 2007Christopher L. Hill The transition from full glacial to interglacial conditions along the southern margin of the Laurentide ice sheet resulted in dramatic changes in landscapes and biotic habitats. Strata and landforms resulting from the Wisconsin Episode of glaciation in the area directly west of Lake Superior indicate a context for late Pleistocene biota (including human populations) connected to ice margins, proglacial lakes, and postglacial drainage systems. Late Glacial landscape features that have the potential for revealing the presence of Paleoindian artifacts include abandoned shorelines of proglacial lakes in the Superior and Agassiz basins and interior drainages on deglaciated terrains. The linkage between Late Pleistocene human populations and Rancholabrean fauna has yet to be demonstrated in the western Lake Superior region, although isolated remains of mammoth ( Mammuthus) have been documented, as well as fluted points assigned to Clovis, Folsom, and Holcombe-like artifact forms. Agate Basin and Hell Gap (Plano-type) artifacts also imply the presence of human groups in Late Glacial landscapes associated with the Agassiz and Superior basins. © 2007 Wiley Periodicals, Inc. [source] Landscape and Coast Development of A Lowland Fjord Margin Following Deglaciation, East GreenlandGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2001Louise Hansen The landscapes of western Jameson Land bordering Hall Bredning fjord comprise upper river basins, glacial landscapes, lower river basins and a near-shore zone. The upper river basins are incised into bedrock and display no cover of young sediments whilst the glacial landscapes, located closer to the coast, are dominated by Pleistocene deposits and an irregular topography with hills and ridges. The lower river basins, dissecting the glacial landscapes, are connected to the upper river basins and contain well-defined Holocene delta terraces. The near-shore zone, which includes the present coast, displays a few raised shorelines. Geomorphological observations combined with stratigraphic work and 14C dates provide a chronological framework for the development of landscape and shoreline, as presented by a four-stage reconstruction. The first stage covers the deglaciation of western Jameson Land at the Weichselian-Holocene transition after a collapse of the main fjord glacier in Hall Bredning. The sea inundated the low-lying areas on Jameson Land forming small side-entry fjord basins that possibly follow the track of older valleys. This was followed by a second stage, the paraglacial period, when large meltwater production and sediment transport resulted in a fast infilling of the side-entry fjord basins by deltas. These are now exposed in terraces in the lower river basins at 70,80 m a.s.l. During a third stage, the relaxation period, fluvial activity decreased and the land surface was increasingly occupied by a cover of tundra vegetation. A glacio-isostatic rebound resulted in a relative sea level fall and fluvial incision. During stages two and three the coast was exposed to shallow marine processes that aided the alignment of the coast. Stages one to three presumably lasted for less than 2000 years. During stage four, the stable period, lasting for several thousand years till the present, there were minor adjustments of shoreline and landscape. The four-step reconstruction describes the sedimentary response of a lowland fjord margin to dramatic changes in climate and sea level. The distribution of erosion and sedimentation during this development was mainly controlled by topography. The reconstruction of the latest environmental development of Jameson Land puts new light on Jameson Land's long and complex Quaternary stratigraphic record. The reconstruction may also be used as a model for the interpretation of deposits in similar areas elsewhere. [source] The Quaternary of the British Isles and adjoining seas,JOURNAL OF QUATERNARY SCIENCE, Issue 4 2010James Rose Abstract This Special Issue of the Journal of Quaternary Science contains a set of 13 papers based on presentations at the Annual Discussion Meeting of the Quaternary Research Association held in London in January 2008. This Special Issue is concerned with four main themes: long-term landscape signatures, river landscapes and responses to climate change, glacial landscapes and Lateglacial landscapes. The papers include substantial new data on the terrestrial and offshore Quaternary of the British Isles and provide a benchmark for aspects of current thinking on this topic. This volume is published in parallel with other special issues based on the 2008 QRA Discussion Meeting. These consist of The Quaternary Geology of the British Isles edited by David Bridgland and Nick Golledge in the Proceedings of the Geologists' Association and Climate variability of the British Isles and surrounding seas edited by Dan Charman and Danny McCarroll in Quaternary Science Reviews. Copyright © 2010 John Wiley & Sons, Ltd. [source] | ||||||||||