Saksunarvatn tephra

Saksunarvatn tephra

In the new science of tephrochronology, Saksunarvatn tephra are volcanic ejecta that form an ash layer that is useful in dating Northern European sediment layers that were laid down during the Boreal period, the warm climate phase that followed the cold snap of the Younger Dryas as the earth made the transition from the last Pleistocene glaciation to the current interglacial, or Holocene. This was a period of rapid climatic transitions around the North Atlantic, some of which took place during a matter of decades. Similar effects are evident in independent palaeoclimatic reconstructions obtained from pollen zones, marine and ice-core records, but these sequences cannot be reliably calibrated with one another. The ash layer from a specific volcanic event, deposited simultaneously over wide areas, provides a common reference point or time marker called a horizon, which establishes simultaneity in the sequences wherever that layer is found: this set of techniques is called tephrochronology.

Radiocarbon dating establishes a date for the Saksunarvatn tephra of ca 10.200 years BP calibrated, during the late Pre-Boreal climatic phase of rapid warming. The volcanic event happened on Iceland. The name commemorates the site where the ash layer was initially recognized, Lake Saksunarvatn on the island of Streymoy in the Faroe Islands, described by Waagstein and Johansen, 1968.

References

* [http://www.colorado.edu/INSTAAR/AW2004/get_abstr.html?id=67 International Arctic Workshop, 2004. Stefan Wastegård et al., "Towards a tephrochronology framework for the last glacial/interglacial transition in Scandinavia and the Faroe Islands": (Abstract)]


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • Tephrochronology — is a geochronological technique that utilises discrete layers of tephra mdash;volcanic ash from a single eruption mdash;to create a chronological framework in which paleoenvironmental or archaeological records can be placed. Such an established… …   Wikipedia

  • Boreal (period) — In paleoclimatology of the Holocene, the Boreal was the first of the Blytt Sernander sequence of north European climatic phases that were originally based on the study of Danish peat bogs, named for Axel Blytt and Rutger Sernander, who first… …   Wikipedia

  • Dye 3 — is an ice core site and previously part of the Distant Early Warning (DEW) line, located at (65°11′N 43°49′W / 65.183°N 43.817°W / 65.183; 43.817 ( …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”