The timing and pattern of the deglaciation of the Eurasian ice sheet is of key importance for Late Quaternary environments, on a local scale as well as globally. The increasing resolution of glacier and climate models demand detailed information about the deglaciation on a calendar year time scale. This is the rationale for the ongoing project DATED, which is aimed to serve as a primary source of information about the ice growth towards LGM and the deglaciation of Eurasia. Data compiled from the literature is presented as a Geographical Information System (GIS) containing digitized ice margins and other features relevant for the deglaciation reconstruction. The GIS is coupled to a Microsoft Access™ database containing deglaciation dates with stratigraphic information. The area comprised in DATED includes all areas covered by the NW-Eurasian ice sheets.

In areas with conflicting ice margin locations, the original lines are edited to construct a consistent and glaciologically plausible pattern in the GIS. This is performed in collaboration with the relevant authors, with the additional aid of stratigraphic information, satellite images, and high-resolution DEMs. Such modifications are stored separately in the GIS, with thorough referencing.

The database is aimed to cover all available dates of the Eurasian deglaciation, based on radiocarbon (¹⁴C), optically stimulated luminescence (OSL), thermoluminescence (TL), cosmogenic exposure (e.g. ¹⁰Be, ³⁶C1), and clay varve records. The database will include ice growth towards the LGM, and therefore start with dates of the Alesund Interstadial, с 35-38 cal kyr BP. All dates in the database are (also) given in a format considered to represent calendar years, using INTCAL04 where applicable.

The dating database and the GIS will be available on the web and successively updated. The dating database is referred to as the Database on Eurasian Deglaciation Dates (DATED 1) and the GIS as the Digital Atlas of the Eurasian Deglaciation (DATED 2).

The main purpose with DATED is to serve as an updated source of interpreted ice margins and dates for the deglaciation of the Eurasian ice sheet, in order to provide accurate digital maps with calendar year isochrones to modelers and other researchers. It will also show where data is lacking, and facilitate re-interpretation of the deglaciation pattern. The first version of DATED will be published and made available on the internet in August 2007, in a format readable with ordinary web-browsers. This task is a part of the British-Dutch-Norwegian co-operative project Ocean Reconstruction and Modelling of the European deglaciation (ORMEN) led by Sandy Harrison, University of Bristol. Information about the DATED project can be found at http://www.gyllencreutz.se.

Reference:

Gyllencreutz R., Mangerud J., Svendsen J.-I., Lohne O. DATED - a dating database and GIS-based reconstruction of the Eurasian deglaciation . Correlation of Pleistocene Events in the Russian North. International Workshop Abstracts. 4-6 December 2006. Saint-Petersburg, 2006, p. 38.