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Showing 1 to 6 of 6 for “"Tephrostratigraphy"”.
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Tephrostratigraphy, petrography, geochemistry, age and fossil record of the Ganigobis Shale Member and associated glaciomarine deposits of the Dwyka Group, Late Carboniferous, southern Africa
Thin, pyroclastic marker beds are preserved in argillaceous units of the Dwyka Group in southern Nambia and South Africa which are the earliest witnesses of volcanism in Karoo-equivalent strata of southern Africa. The aim of this study is to present the field appearance of these marker beds, to …
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Explosive Volcanism in the Kenyan Rift: A Tephrostratigraphic Perspective
… on eruption histories. The complete Holocene tephrostratigraphy for Lake Chala includes 26 cryptotephra deposits and two visible tephra layers deposited between 13,350 and 63 cal yrs BP. Cryptotephra analysis has almost doubled the number of tephras known in the full (~260 kyr) Lake Chala …
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The use of physical and chemical techniques in the identification of Tephera (volcanic ash) in the North Island, New Zealand
… is no longer adequate to resolve the problems of tephrostratigraphy, particularly in areas far from the likely volcanic source. In such areas the deposits are thin, and consequently more strongly weathered, as they are more or less continually involved in soil development processes. Under such …
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Studies on late Quaternary tephras in the Waikato and other regions in northern North Island, New Zealand, based on distal deposits in lake sediments and peats
Aspects of late Quaternary tephrostratigraphy and tephrochronology of the Waikato and other regions in northern North Island, New Zealand, are investigated using distal tephras contained in lake sediments and peats. Such environments are advantageous for tephra studies, particularly in distal …
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Late Quaternary palaeoenvironments and Middle-Late Stone Age habitat preferences in the Nakuru-Naivasha Basin, Kenya: phytolith-based evidence from the site of Prospect Farm
… imagined. A new Ar40/Ar39 based chronology and tephrostratigraphy for the site is ongoing; but the environmental variation at Prospect Farm agrees with local lacustrine records and suggests that glacial-interglacial cycles had a significant effect on the basin’s vegetation history and climate. …