Near-Vertical and Wide-Angle Seismic Surveys in the Schwarzwald

Autor: H. Wilhelm, A. Krohe, D. Menges, W. Janoth, Friedemann Wenzel, Th. Rühl, R. Stenger, Ewald Lüschen, G. Eisbacher, K.-J. Sandmeier, M. Stiller, F. Keller, R. Thomas, W. Söllner, Karl Fuchs
Rok vydání: 1989
Předmět:
Zdroj: Exploration of the Deep Continental Crust ISBN: 9783642745904
Popis: A unified seismic exploration program, consisting of 345 km of deep reflection profiling, a 200 km refraction profile, an expanding spread profile and near surface high-resolution measurements, revealed a strongly differentiated crust beneath the Black Forest. The highly reflective lower crust contains numerous horizontal and dipping reflectors at depths of 13–14 km down to the crust-mantle boundary (Moho). The Moho appears as a flat and horizontal first order discontinuity at a relatively shallow level of 25–27 km above a transparent upper mantle. In the seismic model based on near-vertical and wide-angle data the lower crust consists of lamellae with an average thickness of about 100 m and velocity contrasts increasing with depth. The upper crust is characterized by a discontinuous pattern of mostly dipping reflectors which are related to Hercynian overthrusting and accretion and to late-Hercyni an extensional faulting. A bright spot at 9.5 km depth is interpreted to be due to low-velocity material. The lower part of the upper crust appears as a relatively transparent zone which is also identified as a low-velocity zone situated directly above the laminated lower crust.
Databáze: OpenAIRE