Palaeo-Maar Mýtina

At the southern margin of the Tertiary Cheb-Basin (Czech Republic – NW Bohemia) intense geo-tectonical, geophysical, and geochemical investigations (carried out by the Czech Academy of Sciences Prague, and the Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum) gave strong hints for the existence of a late Quaternary, volcanic palaeo-lake (Geissler et al., 2004, 2007, Mrlina et al., 2007).

The prospected structure, in close vicinity of the famous Eisenbühl/Železná Hůrka - volcano, has become the subject of common studies of GFZ Potsdam (sections 1.3, 3.3 and 4.3) and the Geophysical Institute of CAS Prague. A preliminary drilling in November / December 2007 recovered at least 84 m of lake sediments, consisting of predominantly minerogenic, cold-time lake sediments with intercalations of laminated interstadial / interglacial highly organic deposits. Thus already the first core, in combination with field studies of volcaniclastic deposits, produced evidence for the existence of a former Maar lake at Mýtina. With the expertise of sedimentologists from GFZ section 3.3 lake sediments will be investigated preferably for palaeoclimate proxies, whereas geologists and geochemists from GFZ section 4.3 and geophysicists from GFZ section 1.3 and CAS Prague will concentrate on regional and local geophysical models, volcanological and deep biosphere studies. At the background of first dating of related volcanic rocks by Ar-Ar technique (Mrlina et al., 2007), sediments of the Mýtina section could be related to one or more stages between Marine Isotope Stages 2 to 8, which is of major interest especially in relation to other ongoing palaeo-lake studies (e.g. Piànico).

Backer: GFZ, DFG, CAS Prague
Employee: Dr. Jens Mingram, Prof. Dr. Achim Brauer, Dr. Horst Kämpf, Dr. Jens Kallmeyer, Corinna Kroner
Partner: J. Mrlina (CAS Prague), M. Stebich (Senckenberg Weimar)

Lithological profile of the Mýtina-1/2007 drill core

 

Coring in November 2007 at Mýtina

Laminated lake sediment from Mýtina-1/2007