Heldburger gang

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The 679 and 641 m high Gleichberg mountains
View from the Henneberger Warte to the Straufhain, behind the Gleichberge

The Heldburger Gangschar describes a tertiary volcanic system in the Franconian parts of northern Bavaria and southern Thuringia . It is named after the small town of Heldburg , whose surrounding area, the Heldburger Land , belongs entirely to the northern part of the volcanic zone. The term gangschar refers to the fact that only a few of the volcanoes are still preserved as a surface shape, while their former activity can be proven by fissures called “passages”. These corridors are mostly formed in a south-south-west direction, their cross-section is often less than a meter.

By far the most imposing of the volcanic cones still preserved today are the 641 and 679 m high Gleichberg mountains .

location

The Heldburg gang does not represent a self-contained landscape and is mainly divided into the main natural spatial units Grabfeld , Itz-Baunach-Hügelland and Haßberge . To the south of the Main, however , their former activity can also be traced in the respective north of the Steigerwaldvorland , Steigerwald and Franconian Alb . Its core zone stretches from Hildburghausen in the north-northeast to Gerolzhofen in the south-southwest, but the basalt deposit on the volcano of Oberleinleiter in the north of the Franconian Jura is also attributed to the volcanic system.

Volcanic cone

The most famous preserved volcanic cones are listed below, their height above sea level in brackets and, if known, their estimated age and rock as well as the natural area below :

Older volcanoes such as the Oberleinleiter volcano in the Franconian Alb (31 million years old, olivine melilite hephelinite and olivine nephelinite) are no longer recognizable as a surface shape. The latter reaches a height of 505 m, but is completely sunk into the Jura rocks of the Alb.

See also

literature

  • Gerd Geyer, Hermann Schmidt-Kaler: Coburger Land and Heldburger Gangschar: Walks in the history of the earth. Verlag Pfeil, Munich 2006; ISBN 978-3899370683
  • Gottfried Hofbauer: Volcanoes in Germany. Scientific Book Society, Darmstadt 2016; ISBN 978-3-534-26824-5
  • HG Huckenholz, C.-D. Werner: The tertiary volcanic rocks of the Heldburger Gangschar (Bavarian-Thuringian grave field) . In: European Journal of Mineralogy . tape 2 , supplement 2, 1990, p. 1-42 .

Individual evidence

  1. ↑ a b c The volcano of Oberleinleiter: Traces of a maar in the Northern Franconian Jura - Gottfried Hofbauer, NHG Nuremberg (PDF, 2.47 MB)
  2. ↑ summit z. T. worn away by humans

Coordinates: 50 ° 17 ′ 19 ″  N , 10 ° 43 ′ 43 ″  E