Seismic signature of the Alpine indentation, evidence from the Eastern Alps.

Author(s)
Irene Bianchi, Götz Bokelmann
Abstract

The type of collision between the European and the Adriatic plates in the easternmost Alps is one of the most interesting questions regarding the Alpine evolution. Tectonic processes such as compression, escape and uplift are interconnected and shape this area. We can understand these ongoing processes better, if we look for signs of the deformation within the Earth's deep crust of the region. By collecting records from permanent and temporary seismic networks, we assemble a receiver function dataset, and analyze it with the aim of giving new insights on the structure of the lower crust and of the shallow portion of the upper mantle, which are inaccessible to direct observation. Imaging is accomplished by performing common conversion depth stacks along three profiles that crosscut the Eastern Alpine orogen, and allow isolating features consistently persistent in the area. The study shows a moderately flat Moho underlying a seismically anisotropic middle-lower crust from the Southern Alps to the Austroalpine nappes. The spatial progression of anisotropic axes reflects the orientation of the relative motion and of the stress field detected at the surface. These observations suggest that distributed deformation is due to the effect of the Alpine indentation. In the shallow upper mantle right below the Moho interface, a further anisotropic layer is recognized, extended from the Bohemian Massif to the Northern Calcareous Alps.

Organisation(s)
Department of Meteorology and Geophysics
Journal
Journal of Geodynamics
Volume
82
Pages
69-77
No. of pages
9
ISSN
0264-3707
DOI
https://doi.org/10.1016/j.jog.2014.07.005
Publication date
12-2014
Peer reviewed
Yes
Austrian Fields of Science 2012
105106 Geodynamics, 105102 General geophysics
Keywords
ASJC Scopus subject areas
Earth-Surface Processes, Geophysics
Portal url
https://ucrisportal.univie.ac.at/en/publications/f804188a-c0a6-46fe-bc03-f92052a7d7e8