Nappe stacking resulting from subduction of oceanic and continental lithosphere below Greece

Abstract

We quantitatively investigate the relation between nappe stacking and subduction in the Aegean region. If nappe stacking is the result of the decoupling of upper-crustal parts (5-10 km thick) from subducting lithosphere, then the amount of convergence estimated from balancing the nappe stack provides a lower limit to the amount of convergence accommodated by subduction. The balanced nappe stack combined with the estimated amount of completely subducted lithosphere indicates 700 km of Jurassic and 2400 km of post-Jurassic convergence. From seismic tomographic images of the underlying mantle, we estimate 2100-2500 km of post-Jurassic convergence. We conclude that (1) the imaged slab represents the subducted lithosphere that originally underlay the nappes, (2) since the Early Cretaceous, subduction in the Aegean has occurred in one single subduction zone, and (3) the composition of the original basement of the nappes indicates that at least 900 km of sub-upper-crust continental lithosphere subducted in the Aegean. This paper benefited from thorough reviews of Laurent Jolivet and Mark Brandon. We thank Herman van Roermund and Manfred van Bergen for comments on earlier versions of this manuscript. This is an ISES and VMGS publication.

A map-view restoration of the Alpine-Carpathian-Dinaridic system for the Early Miocene

“…offshore Albania appears to be relatively small (Picha 2002) while by far more substantial shortening occurred across the more internal budva-cukali or Krasta-Pindos Zone during the Neogene (Kilias et al 2001). Note that Neogene to recent shortening in the Hellenides, however, occurred in a more external domain, in front of the Gavrovo-tripolitza Zone (van Hinsbergen et al 2005).…”

Kinematic reconstructions and magmatic evolution illuminating crustal and mantle dynamics of the eastern Mediterranean region since the late Cretaceous

“…the Budva-Cukali zone [Robertson and Karamata, 1994]) to the Aegean domain in the southeast and possibly as far as the Lycian basin in the Taurides [Bonneau, 1984]. This basin had an original width of at least 300 km [van Hinsbergen et al, 2005b].…”

“…Cretaceous to Paleocene during the accretion of the ~200 km wide Pelagonian carbonate platform (figure 5) [Ricou et al, 1998;van Hinsbergen et al, 2005b].…”

“…Located southwest of the Rhodope massif, the Hellenides is a W-to SW-vergent nappe stack constituted by several continental and oceanic units of low-metamorphic grade (figures 1, 4 and 6) [Aubouin, 1959;van Hinsbergen et al, 2005b].…”

Peri-equatorial paleolatitudes for Jurassic radiolarian cherts of Greece

“…The figure also shows the location of previous paleomagnetic studies discussed in the text (Localities/Age/Reference): 1/Pliocene (Laj et al, 1982); 2/Middle to Upper Cretaceous (Morris, 1995); 3/Oxfordian (Morris, 1995); 4/Middle Jurassic (Pucher et al, 1974); 5/Toarcian to Middle Jurassic (Morris, 1995); 7/Middle Jurassic (Surmont, 1989); 8/Trias (Morris, 1995); 9/Trias (Muttoni et al, 1997); 10/Miocene (Morris, 1995); 11/Plio-Pleistocene ( van Hinsbergen et al, 2005a); 12/Plio-Pleistocene ( van Hinsbergen et al, 2005a); 13/lower Oligocene (van Hinsbergen et al, 2005a). tectonic block and northward underthrusting of the African plate beneath the Aegean Sea probably caused the CW rotations (Kissel et al, 2003;van Hinsbergen et al, 2005b).…”