DYNAMICS and ACTIVE PROCESSES - International Lithosphere ...

ILP TASK FORCE on SEDIMENTARY BASINS
2010 International Workshop
November 7-12, 2010, Tirana (Albania)
The DINARIDES-HELLENIDES as a PART of the CARPATHIANS-ALPS SYSTEM:
ANCIENT and RECENT REORGANIZATIONS of a COMPLEX SYSTEM of
MOUNTAIN CHAINS
SCHMID Stephan M. 1 , BERNOULLI Daniel 2 , FUGENSCHUH, B. 3 , MATENCO L. 4 ,
OBERHANSLI, R. 5 , SCHEFER, S. 2 and USTASZEWSKI K. 6
1
Geologisch-Paläontologisches Institut Universität Basel & Geophysical Institute ETH
Zürich, Switzerland, Stefan.Schmid@unibas.ch
2
Geologisch-Paläontologisches Institut Universität Basel, Switzerland,
Daniel.Bernoulli@unibas.ch & Senecio.Schefer@unibas.ch
3
Geology & Paleontology Innsbruck University, Austria, Bernhard.Fuegenschuh@uibk.ac.at
4
Department of Tectonics Vrije Universiteit Amsterdam, The Netherlands,
liviu.Matenco@falw.vu.nl
5
Institut für Geowissenschaften Universität Potsdam, Germany, roob@geo.uni-potsdam.de
6
GFZ German Research Centre for Geosciences, Potsdam, Germany, kamilu@gfz-
potsdam.de
A previously published tectonic overview of the Alps, Carpathians and Dinarides (Fig. 1;
Schmid et al. 2008) is extended to the Hellenides and further into the Taurides and Pontides of
Western Turkey. We focus on the discussion of along strike similarities and differences of this
orogenic system. Some of the differences are due to ancient (i.e. pre-Miocene) reorganizations
related to the opening and closing of the various branches of Tethys (Alpine Tethys,
Neotethys, Paleotethys). Others, however, are due to young and rather dramatic modifications
of a pre-existing orogenic system. Such Miocene to recent reorganizations are associated with
processes of slab break-off and/or slab-roll back, backarc extension and substantial strike-slip
displacements between large composite blocks or microplates such as the so-called Alcapa,
Tisza and Dacia Mega-Units.
The Dinarides are juxtaposed with the Alps along the present-day Mid-Hungarian fault zone
(a former transform fault). The Dinarides represent an orogen of opposite subduction polarity
with respect to the Alps. Since about 20Ma ago the easternmost Alps acquired the Dinaridic
subduction polarity, whereby Adria now represents the lower plate (Ustaszewski et al. 2008).
The architecture of the Dinarides can be traced into the Hellenides without difficulty. Major
along strike lateral changes are modest and the main problems encountered during
compilation are of nomenclatural nature since the names given to the various units
unfortunately change every time a national boundary is crossed. Both Dinarides and
Hellenides consist of thrust sheets that formed in Late Cretaceous to Cenozoic times and are
built up of Adria-derived continental material and previously obducted ophiolites. These
thrust sheets are located in a lower plate position with respect to the upper plate, i.e. the Tisza
and Dacia Mega-Units in the northern and southern Dinarides, respectively, and, at least
temporarily, by the Rhodopes including the Circum-Rhodope belt in the Hellenides (e.g. van
Hinsbergen et al. 2005). The latter extend eastwards into the Pontides of Western Turkey
(Okay 2008). All these upper plate Mega-Units have European affinities. However, those in
the east also incorporate older sutures formed during the closing of Paleotethys. These upper
plate units are separated from the lower plate units, i.e. the units that are commonly referred to
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