GRANU 95

The goal of the project GRANU 95 was an seismic investigation of the Saxothutingian zone of the Variscian foldbelt. A special focus was the saxonian Granulitgebirge and the question of its origin. Another adressed problem was the SW extension of the Saxothuringian zone and its relationship to the Muenchberger Gneissmasse. To solve this topics two refraction seismic lines were measured running from SW to NE (line B) with a total length of 260 km and an perpendicular profile of 90 km length crossing the main line in the center of the Granulitgebirge (line A). 8 shots were fired along line B and 4 shots on profile A. The results show on line A a significant change of the velocities in the upper crust. Towards the Erzgebirge low velocities (6.1 km/s) extend down to a depth of about 8 km indicating a differnt composition of this unit. The Gera-Jachymov-zone is detected only in the uppermost kilometer as a low velocity structure. In the velocity model the Granulitgebirge dosen't display any significant feature. Along both profiles the Moho was detected at depths of 30-31 km. See also link.

Principal Investigators  

• Claus Prodehl (University of Karlsruhe)
• A. Schulze (GFZ))

Cooperation  

• University of Karlsruhe

Experiment time frame  

• spring 1995
• near-vertical experiment - November 1995

Methods & equipment  

• wide-angle reflection/refraction - 130 stations (100 PDAS and 30 Refteks) from the GIPP
• near-vertical reflection - Contractor Geco-Prakla

For detailed information about the near-vertical seismic experiment see GRANU'95  under DEKORP.


Publications  

• U. Enderle, K. Schuster, C. Prodehl, A. Schulze, J. Bribach: The refraction seismic experiment GRANU 95 in the Saxothuringian belt, southeastern Germany Geophys. J. Int. (1998) 133, 245-259.
• C. Krawczyk, E. Stein, S. Choi, G. Oettinger, K. Schuster, H.J. Goetze, V. Haak O.Oncken, C. Prodehl, A. Schulze: Geophysical constraints on exhumation mechanism of high-pressure rocks- the Saxo-Thuringian case between Franconian Line and Elbe Zone in W. Franke, V. Haak, O.Oncken and D. Tanner(eds.), Orogenic processes: quantification and modelling in the Variscian Belt, Special Publications 179, Geol. Soc. London, London, 303-322

For more information contact M. Stiller