From mantle to crust: Stretching the Mediterranean

The origin of forces driving the deformation of the continental crust near subduction zones and especially in backarc
regions is debated. Thiswork is based on a compilation of SKS fast splitting directions that give an image of flowlines
in themantle around theMediterranean subduction zones and a comparisonwith stretching and shear directions in
metamorphic core complexes that show the pattern of deformation at the scale of the middle and lower crusts.We
find that : (1) the two sets of directions are parallel in the three main backarc regions, namely the Alboran Sea, the
Tyrrhenian Sea and the Aegean Sea showing that the lithosphere deformswith the samedirection of stretching in the
crust and themantle, suggesting that (2) crustal deformation ismainly driven frombelowby slab retreat, and (3) the
lithospheric fabric is reset within a few millions of years in backarc environments.

Armijo, R., Meyer, B., King, G.C.P., Rigo, A., Papanastassiou, D., 1996. Quaternary
evolution of the Corinth Rift and its implications for the Late Cenozoic evolution of
the Aegean. Geophys. J. Int. 126, 11–53.
Augier, R., Jolivet, L., Robin, C., 2005. Late orogenic doming in the eastern Betics: final
exhumation of the Nevado–Filabride complex and its relation to basin genesis.
Tectonics 24, TC4003. doi:10.1029/2004TC001687.
Baccheschi, P., Margheriti, L., Steckler, M.S., 2007. Seismic anisotropy reveals focused
mantle flow around the Calabrian slab (Southern Italy). Geophys. Res. Lett. 34,
L05302. doi:10.1029/2006GL028899.
Bank, C.G., Bostok, M.G., Ellis, R.M., Cassidy, J.F., 2000. A reconnaissance teleseismic
study of the upper mantle and transition zone beneath the Archean Slave craton in
NW Canada. Tectonophysics 319, 151–166.
Barruol, G., Deschamps, A., Coutant, O., 2004. Mapping upper mantle anisotropy
beneath SE France by SKS splitting: evidence for a Neogene asthenospheric flow
induced by the Apulian slab rollback and deflected by the deep Alpine roots.
Tectonophysics 394, 125–138.
Barruol, G., Granet, M., 2002. A tertiary asthenospheric flow beneath the southern
French Massif Central related to the west Mediterranean extension evidenced by
upper mantle seismic anisotropy. Earth Planet. Sci. Lett. 202, 31–47.
Barruol, G., Souriau, A., 1995. Anisotropy beneath the Pyrenees range from teleseismic
shear wave splitting. Geophys. Res. Lett 22, 493–496.
Barruol, G., et al., 1998. Lithospheric anisotropy beneath the Pyrenees from shear wave
splitting. J. Geophys. Res. 103, 30039–30054.
Becker, T.W., 2008. Azimuthal seismic anisotropy constrains net rotation of the
lithosphere. Geophys. Res. Lett. 35, L05303. doi:10.1029/2007GL032928 (Correction:
2008GL033946).
Becker, T.W., Schulte-Pelkum, V., Blackman, D.K., Kellog, J.B., O'Connell, R.J., 2006.
Mantle flow under the western United States from shear wave splitting, Earth
Planet. Sci. lett. 247, 235–251.
Behn, M.D., Conrad, C.P., Silver, P.G., 2004. Detection of upper mantle flow associated
with the African Superplume. Earth and Planet. Sci. Lett. 224, 259–274.
Bijwaard, H., Spakman, W., Engdahl, E.R., 1998. Closing the gap between global and
regional mantle tomography. J. Geophys. Res. 103, 30055–30078.
Buick, I.S., Holland, T.J.B., 1989. The P–T–t path associated with crustal extension, Naxos,
Cyclades, Greece. In: Daly, J.S. (Ed.), Evolution of metamorphic belts: Geol. Soc.
Spec. Pub. pp. 365–369.
Bokelmann, G.H.R., 2002a. Convection-driven motion of the North American craton:
evidence from P-wave anisotropy. Geophys. J. Int. 148, 278–287.
Bokelmann, G.H.R., 2002b. Which forces drive North America? Geology 30, 1027–1030.
Buontempo, L., Bokelmann, G.H.R., Barruol, G., Morales, J., 2008. Seismic anisotropy
beneath southern Iberia from SKS splitting. Earth Planet. Sci. Let. 273, 237–250.
doi:10.1016/j.epsl.2008.06.024.
Buttles, J., Olson, P., 1998. A laboratory model of subduction zone anisotropy. Earth
Planet. Sci. Lett. 164, 245–262.
Carminati, E., Wortel, M.J.R., Spakman, W., Sabadini, R., 1998. The role of slab
detachment processes in the opening of the western-central Mediterranean basins:
some geological and geophysical evidence. Earth Planet. Sci. Lett. 160, 651–665.
Choukroune, P., et al.,1986.Deformation andmotion in theWestern Alpine arc. Tectonics 5,
215–226.
Cifelli, F., Mattei, M., Rossetti, F., 2007. Tectonic evolution of arcuate mountain belts on
top of a retreating subduction slab: the example of the Calabrian Arc. J. Geoph. Res.
112 (B09101). doi:10.1029/2006JB004848.
Civello, S., Margheriti, L., 2004. Toroidal mantle flow around the Calabrian slab (Italy)
from SKS splitting. Geophysical Res. Lett. 31 (L10601). doi:10.1029/2004GL019607.
Coney, P.J., Harms, T.A., 1984. Cordilleran metamorphic core complexes, Cenozoic
extensional relics of Mesozoic compression. Geology 12, 550–554.
Crespo Blanc, A., Orozco, M., Garcia-Duenas, V., 1994. Extension versus compression
during the Miocene tectonic evolution of the Betic chain. Late folding of normal
fault system. Tectonics 13, 78–88.
de Boorder, H., Spakman, W., White, S.H., Wortel, M.J.R., 1998. Late Cenozoic
mineralization, orogenic collapse and slab detachment in the European Alpine
Belt. Earth Planet. Sci. Lett. 164, 569–575.
Díaz, J., et al., 2006. Probing seismic anisotropy in north Iberia from shearwave splitting.
Phys. Earth Planet Int. 158 (2–4), 210–225.
Duchêne, S., Aïssa, R., Vanderhaeghe, O., 2006. Pressure–temperature-time evolution of
metamorphic rocks from Naxos (Cyclades, Greece): constraints from thermobarometry
and Rb/Sr dating. Geodynamica Acta 19 (5), 299–319.
Faccenda,M., Burlini, L., Geryal, T.V.,Mainprice, D., 2008. Fault-induced seismic anisotropy
by hydration in subducting oceanic plates. Nature 455, 1097–1100. doi:10.1038/
nature07376.
Faccenna, C., Funiciello, F., Giardini, D., Lucente, P., 2001. Episodic back-arc extension
during restricted mantle convection in the Central Mediterranean. Earth Planet. Sci.
Lett. 187, 105–116.
Faccenna, C., Piromallo, C., Crespo-Blanc, A., Jolivet, L., Rossetti, F., 2004. Lateral slab
deformation and the origin of the Western Mediterranean arcs. Tectonics 23.
doi:10.1029/2002TC001488.
Faccenna, C., Speranza, F., D'Ajello Caracciolo, F., Mattei, M., Oggiano, G., 2002.
Extensional tectonics on Sardinia (Italy): insights into the arc–back-arc transitional
regime. Tectonophysics 356, 213–232.
Fellin, M.G., Picotti, V., Zattin, M., 2005. Neogene to Quaternary rifting and inversion in
Corsica: retreat and collision in the western Mediterranean. Tectonics 24, 2198.
doi:10.1029/2000JB000093.
Flesch, L.M., et al., 2005. Constraining the extent of crust–mantle coupling in central Asia using
GPS, geologic, and shear wave splitting data Earth and Planet. Sci. Lett. 238, 248–268.
Funiciello, F., et al., 2006. Mapping mantle flow during retreating subduction:
laboratory models analyzed by feature tracking. J. Geophys. Res. 111, B03402.
doi:10.1029/2005JB003792.
Gautier, P., Brun, J.P.,1994a. Crustal-scale geometry and kinematics of late-orogenic extension
in the central Aegean (Cyclades and Evvia island). Tectonophysics 238, 399–424.
Gautier, P., Brun, J.P., 1994b. Ductile crust exhumation and extensional detachments in
the central Aegean (Cyclades and Evvia islands). Geodinamica Acta 7 (2), 57–85.
Goetze, C., Evans, B., 1979. Stress and temperature in the bending lithosphere as
constrained by experimental rock mechanics. Geophys. J. R. Astron. Soc. 59, 463–478.
Granet, M., Glahn, A., Achauer, U., 1998. Anisotropic measurements in the Rhinegraben
area and the French Massif Central: geodynamic implications. Pure Appl. Geophys.
151, 333–364.
Grasemann, B., Petrakakis, K., 2007. Evolution of the Serifos Metamorphic Core
Complex. In: Lister, G., Foster, M. (Eds.), Inside the Aegean Core Complexes: Journal
of the Virtual Explorer. Electronic Edition.
Hatzfeld, D, et al., 2001. Shear wave anisotropy in the upper mantle beneath the Aegean
related to internal deformation. J. Geophys. Res. 106 (B12), 30737–30754.
Healy, D., Reddy, S.M., Timms, N.E., Gray, E.M., Brovarone, A.V., 2009. Trench-parallel
fast axes of seismic anisotropy due to fluid-filled cracks in subducting slabs Earth
Planet. Sci. Lett. doi:10.1016/j.epsl.2009.03.037.
Huet, B., Labrousse, L. and Jolivet, L., 2009. Thrust or detachment? Exhumation
processes in the Aegean: insight from a field study on Ios (Cyclades, Greece).
Tectonics accepted with minor modifications.
Jackson, J., 2002. Strength of the continental lithosphere: time to abandon the jelly
sandwich? GSA Today 4–10 September 2002.
Jolivet, L., et al., 2008. Subduction, convergence and the mode of backarc extension in
the Mediterranean region. Bull. Soc. Géol. France 179 (6), 525–550.
Jolivet, L., Faccenna, C., Goffé, B., Burov, E., Agard, P., 2003. Subduction tectonics and
exhumation of high-pressure metamorphic rocks in the Mediterranean orogens.
Am. J. Sci. 303, 353–409.
Karato, S., Jung, H., Katayama, I., Skemer, P.A., 2008. Geodynamic significance of seismic
anisotropy of the upper mantle: new insights from laboratory studies. Ann. Rev.
Earth Planet. Sci. 36, 59–95.
Kincaid, C., Griffiths, R.W., 2003. Laboratory models of the thermal evolution of the
mantle during rollback subduction. Nature 425, 58–62.
Kissel, C., Laj, C., 1988. The Tertiary geodynamic evolution of the Aegean arc: a
paleomagnetic reconstruction. Tectonophysics 146, 183–201.
Kreemer, C., Chamot-Rooke, N., Le Pichon, X., 2004. Constraints on the evolution and
vertical coherency of deformation in the Northern Aegean from a comparison of
geodetic, geologic and seismologic data. Earth Planet. Sci. Lett. 225, 329–346.
Lister, G.S., Banga, G., Feenstra, A., 1984. Metamorphic core complexes of cordilleran
type in the Cyclades, Aegean Sea, Greece. Geology 12, 221–225.
Little, T.A., Savage, M.K., Tikoff, B., 2002. Relationship between crustal finite strain and
seismic anisotropy in the mantle, Pacific–Australia plate boundary zone, South
Island, New Zealand. Geophys. J. Int. 151, 106–116.
Long, M.D., Silver, P.G., 2008. The subduction zone flow field from seismic anisotropy: a
global view. Science 319, 315–318.
Lucente, F.P.,Margheriti, L., 2008. Subduction rollback, slab breakoff, and induced strain in the
uppermost mantle beneath Italy. Geology 36 (5), 375–378. doi:10.1130/G24529A.1.
Lucente, F.P., Margheriti, L., Piromallo, C., Barruol, G., 2006. Seismic anisotropy reveals
the long route of the slab through the western-central Mediterranean mantle. Earth
Planet. Sci. Lett. 241, 517–529.
Malinverno, A., Ryan, W., 1986. Extension in the Tyrrhenian Sea and shortening in the
Apennines as result of arc migration driven by sinking of the lithosphere. Tectonics 5,
227–245.
Margheriti, L., Lucente, F.P., Pondrelli, S., 2003. SKS splitting measurements in the
Apenninic–Tyrrhenian domain (Italy) and their relationwith lithospheric subduction
and mantle convection. J. Geophys. Res. 108 (B4), 2218. doi:10.1029/2002JB001793.
Marone, F., Romanowicz, B., 2007. The depth distribution of azimuthal anisotropy in the
continental upper mantle. Nature 447 (198–201).
Martinez-Martinez, J.M., Azañon, J.M., 1997. Mode of extensional tectonics in the
southeastern Betics (SE Spain): implications for the tectonic evolution of the peri-
Alboran orogenic system. Tectonics 16 (2), 205–225.
Mattei, M., et al., 2002. The Miocene tectonic evolution of the Southern Tyrrhenian Sea:
stratigraphy, structural and paleomagnetic data from the on-shore Amantea basin
(Calabrian Arc, Italy). Basin Res. 14, 147–168.
McKenzie, D.P., Jackson, J.A., 1986. A block model of distributed deformation by faulting.
J. Geol. Soc. London 143, 349–353.
Mehl, C., Jolivet, L., Lacombe, O., Labrousse, L., Rimmelé, G., 2007. Structural evolution of
Andros Island(Cyclades, Greece): a key to the behaviour of a flat detachmentwithin an
extending continental crust. In: Taymaz, T.,Dilek, Y., Ylmaz, Y. (Eds.), The geodynamics
of the Aegean and Anatolia. doi:10.1144/SP291.3 0305-8719/07/$15.00.
Meissner, R., Mooney,W.D., Artemieva, I., 2002. Seismic anisotropy and mantle creep in
young orogens. Geophys. J. Int. 149, 1–14.
Mercier, J.L., Sorel, D., Simeakis, K., 1987. Change in the state of stress in the overriding
plate of a subduction zone: the Aegean arc from the Pliocene to the Present. Annales
Tectonicae 1 (1), 20–39.
Molnar, P., 1992. Brace-Goetze strength profiles, the partitionning of strike–slip and
thrust faulting at zones of oblique convergence, and the stress–heat flow paradox of
the San Andreas Fault, fault mechanics and transport properties of rocks. Academic
Press Ltd, pp. 435–459.
Molnar, P., Lyon-Caen, H., 1988. Some simple physical aspects of the support, structure,
and evolution of mountain belts. Geol. Soc. Amer. Spec. Pap. 218, 179–207.
Moore, M., England, P., Parsons, B., 2002. Relation between surface velocity field and
shear wave splitting in the South Island of New Zealand. J. Geophys. Res. 107 (B9),
2198 10.1029/2000JB000093.
Morris, A., Anderson, A., 1996. First paleaomagnetic results from the Cycladic Massif,
Greece, and their implications for Miocene extension directions and tectonic
models in the Aegean. Earth Planet. Sci. Lett. 142, 397–408.
Negro, F., Agard, P., Goffé, B., Saddiqi, O., 2007. Tectonic and metamorphic evolution of
the Temsamane units, External Rif (northern Morocco): implications for the
evolution of the Rif and Betic-Rif arc. J. Geol. Soc. London 164, 829–842.
Oldow, J.S., Bally, A.W., Avé Lallemant, H.G., 1990. Transpression, orogenic float, and
lithospheric balance. Geology 18, 991–994.
Piromallo, C., Becker, T.W., Funiciello, F., Faccenna, C., 2006. Three-dimensional
instantaneous mantle flow induced by subduction. J. Geophys. Res. 33, L08304.
doi:10.1029/2005GL025390.
Piromallo, C., Morelli, A., 2003. P wave tomography of the mantle under the Alpine–
Mediterranean area. J. Geophys. Res. 108 (B2), 2065 10.129/2002JB001757.
Platt, J.P., Vissers, R.L.M., 1989. Extensional collapse of thickened continental lithosphere:
a working hypothesis for the Alboran Sea and Gibraltar arc. Geology 17,
540–543.
Plomerová, J., et al., 2006. Seismic anisotropy beneath the Northern Apennines (Italy):
mantle flow or lithosphere fabric? Earth Planet. Sci. Lett. 247, 157–170.
Rosenbaum, G., Lister, G.S., Duboz, C., 2002. Reconstruction of the tectonic evolution of
the Western Mediterranean since the Oligocene. In: Rosenbaum, G., Lister, G.S.
(Eds.), Reconstruction of the evolution of the Alpine–Himalayan orogen: Journal of
the Virtual Explorer, pp. 107–126.
Rossetti, F., Goffé, B., Monié, P., Faccenna, C., Vignaroli, G., 2004. Alpine orogenic P–
T–t-deformation history of the Catena Costiera area and surrounding regions
(Calabrian Arc, southern Italy): the nappe edifice of north Calabria revised with
insights on the Tyrrhenian–Apennine system formation. Tectonics 23 (TC6011).
doi:10.1029/2003TC001560.
Royden, L.H., 1993. Evolution of retreating subduction boundaries formed during
continental collision. Tectonics 12 (3), 629–638.
Salimbeni, S., et al., 2007. Abrupt change inmantle fabric across northern Apennines detected
using seismic anisotropy. Geophys. Res. Lett. 34, L07308. doi:10.1029/2007GL029302.
Sandvol, E., et al., 2003. Shear wave splitting in a young continent–continent collision:
an example from eastern Turkey. Geophys. Res. Lett. 30 (24), 8041. doi:10.1029/
2003GL017390.
Savage, M.K., 1999. Seismic anisotropy and mantle deformation: what have we learned
from shear wave splitting? Rev. Geophys. 37 (1), 65–106.
Savage, M.K., Sheehan, A.F., 2000. Seismic anisotropy and mantle flow from the Great
basin to the Great Plains, western United States. J. Geoph. Res. 105, 13715–13734.
Schermer, E.R., 1993. Geometry and kinematics of continental basement deformation
during the Alpine orogeny, Mt. Olympos region, Greece. J. Struct. Geol. 15 (3–5),
571–591.
Schmid, C., van der Lee, S., Giardini, D., 2004. Delay times and shearwave splitting in the
Mediterranean region. Geophys. J. Int. 159, 275–290.
Silver, P., 1996. Seismic anisotropy beneath the continents: probing the depth of
geology. Annu. Rev. Earth Planet. Sci. 24, 385–432.
Silver, P.G., Holt, W.E., 2002. The mantle flow field beneath western North America.
Science 295, 1054–1057.
Spakman, W., Wortel, R., 2004. A tomographic view on Western Mediterranean
geodynamics. In: Cavazza,W., Roure, F.M., Spakman,W., Stampfli, G.M., Ziegler, P.A.
(Eds.), The TRANSMED Atlas — the Mediterranean region from crust to mantle.
Springer, Berlin, Heidelberg, pp. 31–52.
Tikoff, B., Russo, R., Teyssier, C., Tommasi, A., 2004. Mantle-driven deformation of
orogenic zone and clutch tectonics. In: Grocott, J., McCaffrey, K.J.W., Taylor, G.,
Tikoff, B. (Eds.), Vertical coupling and decoupling in the lithosphere. Geological
Society, London, pp. 41–64. Special Publications.
van Hinsbergen, D.J.J., Langereis, C.G., Meulenkamp, J.E., 2005. Revision of the timing,
magnitude and distribution of Neogene rotations in the western Aegean region.
Tectonophysics 396 (1–2), 1–34.
van Keken, P.E., Kneller, E.A., 2007. Trench-parallel flow and seismic anisotropy in the
Mariana and Andean subduction systems. Nature 450, 1222–1225. doi:10.1038/
nature06429.
Vanderhaeghe, O., 2004. Structural development of the Naxos migmatite dome. In:
Whitney, D.L., Teyssier, C., Siddoway, C.S. (Eds.), Gneiss domes in orogeny.
InGeological Society of America, Boulder, Colorado, pp. 211–227.
Vauchez, A., Tommasi, A., Barruol, G., 1998. Rheological heterogeneity, mechanical
anisotropy and deformation of the continental lithosphere. Tectonophysics 296,
61–86.
Vignaroli, G., Faccenna, C., Jolivet, L., Piromallo, C., Rossetti, F., 2008. Orogen-parallel
extension and arc bending forced by slab tearing and toroidal flow at the junction
between Alps and Apennines. Tectonophysics 450 (1–4), 34–50. doi:10.1016/j.
tecto.2007.12.012.
Watts, A.B., Burov, E.B., 2003. Lithospheric strength and its relationship to the elastic
and seismogenic layer thickness. Tectonophysics 213, 113–131.
Wernicke, B., 1992. Cenozoic extensional tectonics of the U.S. cordillera. In: Burchfiel, B.C.,
Lipman, P.W., Zoback, M.L. (Eds.), The Cordilleran Orogen: conterminous U.S.Geological
Society of America, Boulder, Colorado, pp. 553–581.
Wessel, P., Smith, W.H.F., 1998. New, improved version of generic mapping tools
released, Eos Trans. AGU 79 (47), 579.
Wortel, M.J.R., Spakman, W., 2000. Subduction and slab detachment in the
Mediterranean–Carpathian region. Science 290, 1910–1917.
Zhang, S., Karato, S., 1995. Lattice preferred orientation of olivine aggregates deformed
in simple shear. Nature 375, 774–777.