Tephrochronology

Abstract

Tephrochronology is the use of primary, characterized tephras or cryptotephras as chronostratigraphic marker beds to connect and synchronize geological, paleoenvironmental, or archaeological sequences or events, or soils/paleosols, and, uniquely, to transfer relative or numerical ages or dates to them using stratigraphic and age information together with mineralogical and geochemical compositional data, especially from individual glass-shard analyses, obtained for the tephra/cryptotephra deposits. To function as an age-equivalent correlation and chronostratigraphic dating tool, tephrochronology may be undertaken in three steps: (i) mapping and describing tephras and determining their stratigraphic relationships, (ii) characterizing tephras or cryptotephras in the laboratory, and (iii) dating them using a wide range of geochronological methods. Tephrochronology is also an important tool in volcanology, informing studies on volcanic petrology, volcano eruption histories and hazards, and volcano-climate forcing. Although limitations and challenges remain, multidisciplinary applications of tephrochronology continue to grow markedly.

Late Pleistocene and Holocene tephrostratigraphy of interior Alaska and Yukon: Key beds and chronologies over the past 30,000 years

“…Indirect dating is commonly undertaken using high-precision radiocarbon dating or using layer counting if the record is incremental, such as ice cores or varved lake deposits (e.g. Lowe, 2011;Lowe and Alloway, 2015). Within this study, the term 'date' is used to refer to an indirect and/or unmodelled date produced from material associated with a tephra, and the term 'age' refers to either a direct date, a date representing a maximum or minimum chronological limit, or a modelled outcome combining one or more dates associated with a tephra to estimate the time of deposition.…”

Crossing new frontiers: extending tephrochronology as a global geoscientific research tool

“…Lowe (2011) and Alloway et al . (2013) are key primers on the theory and application of tephrochronology, Davies (2015) outlines the recent revolution in tephrochronology driven by cryptotephra studies, Lowe and Alloway (2015) focus on tephra dating techniques, Lowe et al . (2017) review the methods and best practices for chemically characterising glass shards from tephras and cryptotephras and correlating deposits, and Lane et al .…”

“…Several recent articles provide comprehensive reviews of the history, application and current status of tephrochronology, and are key references for anybody looking to learn more about the technique. Lowe (2011) and Alloway et al (2013) are key primers on the theory and application of tephrochro-nology, Davies (2015) outlines the recent revolution in tephrochronology driven by cryptotephra studies, Lowe and Alloway (2015) focus on tephra dating techniques, Lowe et al (2017) review the methods and best practices for chemically characterising glass shards from tephras and cryptotephras and correlating deposits, and Lane et al (2017b) provide a useful update on various more recent advances.…”

The cultural nature of tephra: ‘Problematic’ ecofacts and artifacts and the Barú volcano, Panamá

“…Tephra studies are increasingly important components of Quaternary research and provide a unique means to address palaeoenvironmental and archaeological chronologies (Lowe, 2011;Lowe and Alloway 2014). The precise relationship between key volcanic eruptions and the archaeological and environmental record can be highly problematic, however, even for heavily studied volcanic events such as the Bronze Age eruption of Santorini/Thera (e.g., Manning, 1999;Pearson et al, 2005;Friedrich et al, 2006;Manning et al, 2006).…”