Clone
The Klonk is a hill near the municipality Suchomasty , Czech Republic , about 35 kilometers southwest of Prague . It represents a geological site of international importance.
The steep slope was established in 1972 as the GSSP (Global Boundary Stratotype Section and Point) for the boundary between the Silurian and Devonian Ages . The GSSP method, which was first used in Klonk, is a method of chronostratigraphy that defines geological periods and their limits in a binding form based on reference profiles. After a selection process from 1969 to 1971, in which areas in question in Europe, Nevada and Morocco were examined, the “Silurian-Devonian Boundary Committee” put the Barrandium as the type area and Klonk as the border stratotype for the two ages firmly. The result was approved by the International Commission on Stratigraphy in Montreal in 1972 .
Klonk met the requirements of the new system in particular because the profile is not disturbed by orographic or tectonic processes. The layers, which are formed here as a succession of limestone and slate , can thus be observed particularly well. Fossils are used to define the Silurian-Devonian boundary . The key fossil is the graptolite Monograptus uniformis , the trilobite Warburgella rugulosa and the conodonts Icriodus woschmidti and Angochitina chlupaci are also of importance .
To protect the locality, a national natural monument was proclaimed in Klonk in 1977 . It is 8.9 hectares and lies at an altitude of 322 to 418 m nm at the north end of the slope. The site is not open to the public.
literature
- Chráněná území České Republiky , vol. 1. Editor: Agentura ochrany přírody a krajiny ČR, Prague 1996. ISBN 80-902132-0-0 (description of the nature reserve)
Web links
- pruvodce.geol.cechy.sci.muni.cz - description of the location, bibliography
- www.uibk.ac.at (PDF; 4.0 MB) - German review of the final report of the “Silurian-Devonian Boundary Committee” (Martinsson, Anders (Ed.): The Silurian - Devonian Boundary. IUGS Ser. A, No. 5, 349 S., Stuttgart (Schweizerbart) 1977).
Coordinates: 49 ° 54 ′ 0 ″ N , 14 ° 4 ′ 0 ″ E