The TRANSALP project is an international and multidisciplinary research program for investigating orogenic processes driven by the collision of continental lithospheric plates. The target area of the Eastern Alps shows the colliding of the Adriatic-African plate with the southward subducting European plate. Structures and orogenic processes of the Eastern Alps are considered paradigmatic for testing plate-tectonic models of continent-continent collision. The project is also motivated by the insight that problems of great practical interest such as earthquake risk assessment or the hydrocarbon potential of the Alps can only be solved with a well-founded understanding of the geodynamic processes, which built the Alps and which are partially still active.
The project consists of two main parts:
The backbone of part (1.) is an almost 340 km long near-vertical
reflection profile between Freising in the north and Treviso in the
south (s. Fig.1). It covers the Eastern Alps and parts of its northern
and southern Molasse Basins. The technique of near-vertical reflection
seismics - developed for hydrocarbon exploration in sedimentary basins
- has become the most powerful tool in geoscience for investigating
lithospheric structure and its history of origins.
Refraction seismics and seismological investigations are further subprojects of (1.) within an integrated framework closely related to the near-vertical reflection seismics.
A large number of accompanying geoscience projects (project part (2.)) are planned in partaking countries and have been partly granted to support TRANSALP by geological, petrological and geochronological investigations.
TRANSALP is a joint venture of researchers in the following national research groups:
Geology and anticipated seismic key structures as proposed before the start of the TRANSALP project:
Based on the surface geology shown in Fig. 2, two tentative cross sections through the Eastern Alps (following approximately the line marked in Fig. 2) were determined (Fig. 3).
These cross sections were unproven extrapolations from the Western Alps (Lammerer, unpublished). Expected seismic key structures and possible reflecting horizons are marked by red italic numbers , indicating the following features:
The European lithosphere is dipping southward with an angle of approx. 3 to 5°. Challenging questions are the following:
The scientific objectives required high structural resolution in the upper crust, similar to industrial exploration, including steeply dipping and complicated 3D structures. Furthermore, penetration of seismic signals deeper than 70 km was required to test existing geodynamic models. These challenging tasks were addressed in several subprojects:
In addition, the near-vertical incidence seismic reflection measurements were combined with several seismological supplementary experiments conducted by personnel and instruments of universities and research institutions. These experiments used the energy sources of the contractor and were to achieve 3-dimensional control on key structures along the main line, better control on seismic velocities at great depths and knowledge of the recent tectonic stress regime. Further details on the subprojects:
The East-Alpine Reflection Seismic Traverse
Download detailed acquisition parameters as .pdf files:
Final TRANSALP Conference
Trieste, 10th - 12th Feb. 2003
TRANSALP - A transect through a young collisional orogen: Introduction
H. Gebrande, A. Castellarin, E. Lüschen, K. Millahn, F. Neubauer and R. Nicolich (p.1)
TRANSALP - deep crustal Vibroseis and explosive seismic profiling in the Eastern Alps
E. Lüschen, D. Borrini, H. Gebrande, B. Lammerer, K. Millahn, F. Neubauer, R. Nicolich and TRANSALP Working Group (p.9)
TRANSALP - Cross-line recording during the seismic reflection transect in the Eastern Alps
K. Millahn, E. Lüschen, H. Gebrande and TRANSALP Working Group (p.39)
Crustal structure of the Eastern Alps along the TRANSALP profile from wide-angle seismic tomography
F. Bleibinhaus and H. Gebrande (p.51)
Wide-angle observations of ALP 2002 shots on the TRANSALP profile: Linking the two DSS projects
F. Bleibinhaus, E. Brückl and ALP 2002 Working Group (p.71)
Reviewing pre-TRANSALP DSS models
R. Cassinis (p.79)
Shallow high-resolution seismics and reprocessing of industry profiles in southern Bavaria: The Molasse and the northern
R. Thomas, K. Schwerd, K. Bram and J. Fertig (p.87)
Experimental and texture-derived P-wave anisotropy of principal rocks from the TRANSALP traverse: An aid for the
interpretation of seismic field data
K. Ullemeyer, S. Siegesmund, P.N.J. Rasolofosaon and J.H. Behrmann (p.97)
Shear wave splitting in the Eastern Alps observed at the TRANSALP network
J. Kummerow, R. Kind and TRANSALP Working Group (p.117)
New gravity maps of the Eastern Alps and significance for the crustal structures
C. Zanolla, C. Braitenberg, J. Ebbing, M. Bernabini, K. Bram, G. Gabriel, H.-J. Götze, S. Giammetti, B. Meurers, R. Nicolich and F. Palmieri (p.127)
The lithospheric density structure of the Eastern Alps
J. Ebbing, C. Braitenberg and H.-J. Götze (p.145)
A review of the thermal regime of the Eastern Alps with respect to the effects of paleoclimate and exhumation
H.-D. Vosteen, V. Rath, C. Clauser and B. Lammerer (p.157)
Paleomagnetic evidence for large en-bloc rotations in the Eastern Alps during Neogene orogeny
W. Thöny, H. Ortner and R. Scholger (p.169)
From Middle Jurassic heating to Neogene cooling: The thermochronological evolution of the southern Alps
M. Zattin, A. Cuman, R. Fantoni, S. Martin, P. Scotti and C. Stefani (p.191)
The Alpine evolution of the Southern Alps around the Giudicarie faults: A Late Cretaceous to Early Eocene transfer zone
A. Castellarin, G.B. Vai and L. Cantelli (p.203)
Structural synthesis of the Northern Calcareous Alps, TRANSALP segment
J.H. Behrmann and D.C. Tanner (p.225)
Kinematics of the Inntal shear zone-sub-Tauern ramp fault system and the interpretation of the TRANSALP seismic section,
Eastern Alps, Austria
H. Ortner, F. Reiter and R. Brandner (p.241)
Structure of the lithosphere beneath the Eastern Alps (southern sector of the TRANSALP transect)
A. Castellarin, R. Nicolich, R. Fantoni, L. Cantelli, M. Sella and L. Selli (p.259)
Kummerow, J., Kind, R., Oncken, O., Giese, P., Ryberg, T., Wylegalla, K., Scherbaum, F. and TRANSALP Working Group, 2004. A natural and controlled source seismic profile through the Eastern Alps: TRANSALP. Earth Planet Sci. Lett. 225, 115-129, doi:10.1016/j.epsl.2004.05.040.
Lippitsch, R.,Kissling, K., and Ansorge, J., 2003. Upper mantle structure beneath the Alpine Orogen from high-resolution teleseismic tomography. J. Geophys. Res. 108 (B8), 5.1-5.15, doi:10.1029/2002JB002016.
Lüschen, E., Lammerer, B., Gebrande, H., Millahn, K., Nicolich, R. and TRANSALP Working Group, 2004. Orogenic structure of the Eastern Alps, Europe, from TRANSALP deep seismic reflection profiling. Tectonophysics 388, 85-102.
TRANSALP Working Group, 2001. European Orogenic Processes Research Transects the Eastern Alps. Eos 82 (40), 453, 460-461.
TRANSALP Working Group, 2002. First deep seismic reflection images of the Eastern Alps reveal giant crustal wedges and transcrustal ramps. Geophys. Res. Lett. 29 (10), 92.1-92.4, doi:10.1029/2002GL014911.