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Geological Society of America
Special Paper 409
2006

Coexisting geodynamic processes in the Sicily Channel

Giacomo Corti
Istituto di Geoscienze e Georisorse, CNR, Pisa, Italy
Marco Cuffaro
Carlo Doglioni*
Dipartimento di Scienze della Terra, Università La Sapienza, Roma, Italy
Fabrizio Innocenti
Dipartimento di Scienze della Terra, Università di Pisa, and
IGG-CNR Pisa, Italy
Piero Manetti
Istituto di Geoscienze e Georisorse, CNR, Pisa, Italy

ABSTRACT

The northwestern side of the Sicily Channel in the central Mediterranean has
been shaped by the occurrence of two independent tectonic processes that overlap each
other, the Maghrebides-Apennines accretionary prism and the Sicily Channel rift.
Since at least the Pliocene, these two processes have acted simultaneously, being re-
spectively related to the Apennines subduction and to the African rift. Thrust sheets
of the accretionary prism crosscut the almost orthogonal rift-related normal faults and
vice versa. Analogue modeling supports the kinematics inferred from regional struc-
tural data. Alkaline magmatism associated with the rift is more pronounced in the
foreland of the prism, where the extension is more concentrated. This peculiar setting
confirms how independently geodynamic processes can interact in the same area at
the same time, suggesting that plate boundaries are passive features responding to far-
field velocity fields of the lithosphere.

Keywords: Mediterranean, Sicily Channel, accretionary prism, rifting, coexisting tectonics

INTRODUCTION consider independent. The coexistence of four independent ge-
odynamic processes was proposed by Doglioni and Carminati
One of the paradigms of plate tectonics is that plate bound- (2002) for northeastern Italy, where the Alpine and Dinaride
aries record the deformation related to the ongoing geodynamic thrust belts interplayed in an area that was undergoing remote
processes, assuming a single tectonic setting. This article deals subsidence due to the Apennines subduction and affected by the
with an expansion of this concept, discussing the possibility that Pannonian back-arc extension. In the western Mediterranean,
in a given area multiple geodynamic processes work together, the Valencia rifting obliquely crosscut the coeval and independ-
overlapping each other and generating a deformational pattern ent Betic orogen (Doglioni et al., 1997, 1998, 1999). Along the
that represents the sum of distinct tectonic styles that we may San Andreas system, two tectonic settings overlap where the

*E-mail: carlo.doglioni@uniroma1.it.
Corti, G., Cuffaro, M., Doglioni, C., Innocenti, F., and Manetti, P., Coexisting geodynamic processes in the Sicily Channel in Dilek, Y., and Pavlides, S., eds.,
Postcollisional tectonics and magmatism in the Mediterranean region and Asia: Geological Society of America Special Paper 409, p. 83–96, doi:
10.1130/2006.2409(05). For permission to copy, contact editing@geosociety.org. ©2006 Geological Society of America. All rights reserved.
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