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Showing 1 to 16 of 16 for “"Tephrochronology"”.
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Carbon Accumulation Rates Over the Holocene in Flow Country Peatlands and the Direct Comparison of Open and Afforested Peatland Carbon Stocks Using Tephrochronology
… between forested and open peatlands, based on tephrochronology, the identification and use of volcanic ash layers to reliably match stratigraphy. We successfully applied this method to four pairs of afforested and open blanket bog sites in the Flow Country. First, ITRAX scanning was tested as a …
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Development of geochemical identification and discrimination by Raman spectroscopy. The development of Raman spectroscopic methods for application to whole soil analysis and the separation of volcanic ashes for tephrachronology
… organic or water-soluble fractions unexamined. Tephrochronology (the dating of sedimentary sequences using volcanic ash layers) is an important tool for the dating and correlation of sedimentary sequences containing archives and proxies of past environmental change. Its importance in this area …
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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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Glacial isostatic adjustment and relative sea level change over the last earthquake cycle in upper Cook Inlet, Alaska, USA
… history of regional gold mining and development, tephrochronology and AMS 14C wiggle match dating. The research highlights some of the limitations of applying some of these dating methodologies to recent, high latitude, salt marshes. GIA modelling identifies part of the GPS measured present day …
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Syntectonic deposition and paleohydrology of the spring-fed Hualapai Limestone and implications for 5-6 MA integration of the Colorado River system through Grand Canyon : evidence from sedimentology, geochemistry and detrital zircon analysis
… analysis that includes new geochemistry, tephrochronology, and detrital zircon analysis to examine variations of the sedimentary and tectonic records from the Hualapai Limestone basins. Thickness variations, with progressively thicker deposits towards the east in two of the four basins, …
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Tree-limit ecotonal response to Holocene climate change in the Scandes Mountains of west-central Sweden
… the project were based on radiocarbon dating and tephrochronology. At Lake Stentjärn, three Holocene cryptotephra horizons were detected, one of which was geochemically correlated with the Icelandic Askja-1875 eruption. At Klocka Bog, at least seven cryptotephra horizons were recorded in the two …
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Characterization of Cenomanian-early Turonian bentonites in southwestern Saskatchewan through lithostratigraphy and chemostratigraphy analysis
… correlation, much in the same way that tephrochronology is applied to young volcanic deposits. Numerous bentonite horizons are preserved within Late Cretaceous strata of western Canada and northern USA, and several widespread layers delineate unit or formation boundaries (e.g., the Clay …
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Mapping and Radiocarbon Dating Archaic Period Monuments: La Alberca Structure Complex, Highland Michoacán, Mexico
… Formative, Archaeology, Earthen Structures, Tephrochronology, Central Mexico, and Parangaricutiro Highlands.
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Explosive Volcanism in the Kenyan Rift: A Tephrostratigraphic Perspective
Traditionally, tephrostratigraphic work in eastern Africa has provided chronological control on archaeological formations, helping to piece together temporal and spatial trends in human evolution. The result is that tephrostratigraphic frameworks in the rift valley are patchy, focus mainly on the …
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Long-range impacts of the ~74 ka Toba super eruption
The ~74 ka Toba super eruption (Indonesia) was the largest Quaternary volcanic event and, thus, has been a topic of debate regarding its possible impact on climate, environment, and eventually, early modern humans. This dissertation was aimed at improving our understanding of the Toba impact by …
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Resolving abrupt palaeoenvironmental changes in a lake sediment sequence from Ioannina, northwest Greece
Palaeoenvironmental sequences from the Mediterranean have, for many years, been a cornerstone of our understanding of ecological responses to Quaternary climate change. Lake Ioannina (NW Greece) is one such archive, with a vegetation record which spans multiple glacial-interglacial cycles. This PhD …
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High-Precision ID-TIMS U-Pb Zircon Geochronology of Three Cenomanian Bentonites from the Western Canada Foreland Basin
The Western Canada foreland basin contains a rich record of Upper Cretaceous marine | and tectonic change, yet is sparse in biostratigraphically useful fauna that permit | continental and global correlation. However, numerous extensive bentonites have been 1 mapped in Cenomanian strata and traced …
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Setting the Holocene clock using varved lake sediments in Sweden
The aim of this thesis was to study annually laminated (varved) Holocene lake sediment in Sweden, their formation and their potential as chronological and palaeoecological archives. Five lakes with continuous Holocene varved lake sediment sequences in northern (Västerbotten) and west central Sweden …