The Eastern Alps, Southern Alps, and northern Dinarides form the northeastern corner of the Adriatic microplate, where due to its counter-clockwise rotation, this plate is currently indenting the Alpine orogenic edifice. The Southern Alps is the seismically most active part of the orogen and coincides with a controversial, proposed switch in slab polarity. North of this active convergent zone, the Eastern Alps have extended eastward into the Pannonian Basin with thinned orogenic lithosphere behind the retreating Carpathian orogen. Investigation of the Alps-Pannonian-Dinarides junction thus offers a unique opportunity to study mechanisms of plate deformation at the transition from head-on continental collision (Alps) and oblique transpression (Dinarides) to rollback subduction (Carpathians).

This orogenic junction lies at the eastern end of the AlpArray Station Network (AASN) and is also covered by two densified station arrays (Complementary Experiments EASI and SWATH-D). We will combine a variety of tectonic, geodetic and seismological methods to interpret incoming data from these arrays in a broad geodynamic framework. Specifically, this collaborative project will address the following basic questions that are relevant to orogenic research: (1) how is crustal seismicity related to the current motion pattern of crustal blocks in the Alps? (2) has this motion pattern changed with time? (3) can the history of crustal motion be related to the geometry of lithospheric slabs and slab gaps at Adria-Europe interface? (4) what is the nature and degree of coupling within the crust and at the crust-mantle boundary during indentation and rollback subduction?

The overall goal is to understand crust-mantle interactions underlying the highly mobile behavior of tectonic plates that is typical of the Alpine collisional belt. This effort is multidisciplinary and to date involves researchers from 19 institutions in 6 countries.