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Tephrochronology is most commonly used as part of Quaternary scientific studies of environmental change, and offers a unique and powerful way of dating and linking different sites and archive types (ice-cores, terrestrial, marine).If the aim is to make such studies of environmental change relevant to human societies the method attains its greatest utility if either reliable proxies of human activity can be identified alongside the tephra, or – better still – if the tephra itself can also be identified within relevant archaeological layers.This is especially relevant for distal occurrences, where volcanic particles are only to be found as crypto- or microtephras, i.e.
In addition, this rise is also the result of increasingly precise and accurate geochemical methods for identifying or ‘fingerprinting’ particles from particular eruptions.
This is usually done via electron microprobe analysis or, occasionally, other analytical approaches.
In brief, tephrochronology thus achieves its greatest utility if and when discrete visible or invisible layers of volcanic particles (a) originate from known-age and short-lived explosive volcanic events that (b) left a widespread deposit of particles, which (c) can be securely identified via petrological and/or geochemical methods.
Knowledge of the source of the tephra is not strictly required and several important isochron markers (e.g.
In order to move towards such integration, a series of methodological challenges have to be met.
We outline some of these, and provide pointers as to how and where tephrochronologists and archaeologists can work together more closely.].Although many characteristic features within a given stratigraphy (e.g.soil horizons, loess layers) can be used to anchor such sequences in time, the process or processes that cause the formation of such similar layers are often transgressive in time and/or space thus detracting from their general utility as dating and correlation tools.The aim of this paper is not to be comprehensive, but to provide a brief and timely general review of tephra studies and their methodologies, and to make a case for better linking tephra research to archaeology, all from a primarily Scandinavian perspective.We argue that the identification of tephra in archaeological sediments should, in due time, become as routine as other types of geo-archaeological analyses, especially given that tephra cannot only act as a useful chronostratigraphic marker, but can also play a role in changing patterns of environmental and cultural change at the level of the site or the region.Whilst such searches may not accurately reflect the volume of tephra research conducted with archaeological relevance (see discussion in main text), they do suggest that archaeology does remain poorly linked with tephrochronology on the whole.Tags: Adult Dating, affair dating, sex dating