Earthquake, ascending magma, tectonic tensions – why a volcanic eruption in Germany is possible at any time.
Germany is not exactly considered a hotspot for volcanoes – but it is bubbling deep below the Eifel. Geophysical measurements show: Magma rises from the earth’s coat, the earth’s crust rises slowly. So could there be a sudden outbreak? The expert in Volcanism and Tectonics, Ulrich C. Schreiber, explains in an interview with T-Online which forces play a role here and why a volcanic eruption in the Eifel is only a matter of time.
T-online: If you think of volcanoes, the Cumbre Vieja come to La Palma or the Etna. But there are also volcanoes in Germany – where can they be found?
Schreiber: In Germany there are two main areas that are geologically active as volcanic: the Eifel and the Vogtland. There is also a very low probability of a zone north of Lake Constance, which has come into view due to geophysical studies.
There are geological peculiarities in the room between Stuttgart and Lake Constance: Here the earth’s mantle differs slightly from the neighboring regions, and a so -called shear zone triggers tensions in the earth’s crust. This zone is one of the earthquake -prone areas in Germany – and could even open ways to Magma if there is enough of it deep below the surface, as has already happened millions of years ago in the Urach and Hegau volcanic fields. But this also requires the right interaction of tectonic activity and changes in the earth’s mantle.
What does the volcanic activity in the Eifel look like?
The Eifel consists of two clearly distinguishable volcanic regions. Slag cones and Maarvolkanes dominate in the West Eifel. The Osteifel, on the other hand, has a different dynamic: In addition to comparable volcanoes such as in the West Eifel, explosive outbreaks have occurred here in the past, which released large amounts of material in a short time.
Not only magma, but also water and gases are crucial for volcanism. In particular, so -called overcritical fluids – water and CO2 under extreme pressure – play a key role. These substances are high -mobil, penetrate the smallest cracks and can break the earth’s crust. If water then strikes glowingly hot magma, an explosive mix is created that craters can blow out of the ground.
video | Activities in Eifel observed: Germany’s volcanoes are here
How can you imagine that?
The stretching plays a crucial role in this geological process. The earth’s crust is first narrowed and then stretched until it tears. Figure you can imagine it like a tomato that you put together between two fingers: it is squeezed, but at the same time it stretches in the middle – until it bursts.
There are also such stretching effects in the Osteifel, especially in the Neuwied Belzen. In addition to the main inclusion in Northwest-Südost, train tensions appear here in addition to the main inclusion in Northwest Südost. This creates zones in which ascending magma cannot simply break through to the surface. Instead, it collects in chambers – comparable to a garden hose that forms a bump in a soft place in which more and more water collects.
Over time, the composition of the magma in these chambers changes: it becomes more explosive because certain components concentrate. At some point there is so much pressure that there are huge outbreaks. The consequences can still be seen today: the huge crater of the Wehrer Kessel or Laacher Lake are evidence of these processes.
Ulrich C. Schreiber (* 1956 in Osterode am Harz), retired professor of general geology at the University of Duisburg-Essen, where he worked and taught for almost 26 years. His areas of work are the emergence of life, the regional geology of Central Europe, Volcanism and Tectonics as well as geo ecology. In 2003 he discovered a connection between the appearance of hill -building forest ants and gas leading tectonic breaking zones of the earth’s crust. He uses his scientific knowledge for writing activities, for example in his first novel “The Escape of the Ants – a Vulcan Exception on the Rhine” and finally in the Newly published science fiction novel “Die Mirrorung der Zeit”.
This special tectonics explain why the Osteifel has a different volcanic landscape than the West Eifel – and why particularly large explosions were possible here. Which tectonic forces play a role here?
