Terrestrial Palaeoecology and Global Change

158 Valentin A. Krassilov. Terrestrial Palaeoecology
The western Mediterranean is a mosaic of blocks, the better defined of which are the
Iberian, Alboran, Corso-Sardinian, Maltian (Pelagian), Adriatic, Serbo-Macedonian and
the Rhodopic (Fig. 70). They are sutured by the Gibraltar – Baleares, Penninic, Umbrian,
Ligurian, Calabrian, Ionic, Dinarian, Vardar and the less prominent ophiolitic belts
(Aubouin, 1963; Hsü, 1971, 1976, 1977; Bosellini & Hsü, 1973; Dewey et al., 1973;
Vandenberg, 1979). The ophiolites and associated metamorphics are exhumed from beneath
the volcanosedimentary cover and thrust over the Lower Cretaceous foredeep
turbidites that are in turn emplaced, with melanges, upon the block margins, as described
for the Umbrian, Dinaran and Ionic sutures (Celet, 1977; Abbate et al., 1980; Karamata
et al., 1980; Trotet et al., 2000).
These structures appear continuous over northern Africa and southern Europe (Fig.
71). The Bettic –Subbetic belts are linked via Gibraltar arc to their equivalent Maroccan
Rif and Tellian structures, while the Calabrian arc is allied to the Atlassian ophiolite belts.
Whatever the relative motions between European blocks and Africa since the Permian,
they have not disrupted the connections.
The ophiolites are tectonized before emplacement, which indicates a shear zone environment,
such as the Red Sea type leaky strike-slip fault zones injected with peridotite
bodies (Styles & Gerdes, 1983). Their associated silicitic turbidites contain terrestrial
plant remains (Abbate et al., 1980), which rule out a mid-ocean ridge environment, but
are consistent with a ridge – trough structure of a shear fault zone.
Instead of representing a great number of local spreading – subduction events, the
thrust belts are synchronized in their development all over the western Mediterranean.
Fig. 70. Alpine – Mediterranean crustal blocks of the western Tethys belt: (Ad) Adriatic, (I) Iberian, (M)
Moesian, (Ma) Maltian, (P) Pelagian, (Pa) Pannonian, (R) Rhodopian, (T) Transylvanian, (WM) Western
Mediterranean, (G) Gibraltar arc.