420 SELECTED ABSTRACTS

The movement across the Nevado-Filabride shear zones and the convergence of Europe and Africa (Betic orogen)

V. Garcia-Duefias a, F. Gonzalez Lodeiro a, A. Jabaloy a, J.M. Martinez Martinez a

and M. Orozco b

a Departamento de Geodimimica, Instituro Andah de Geologia Mediterrbnea, C.S.I. C., Universidad de Granada, Granada, Spain ’ Departamento de Geologia, Vniversidad de Sevilla, Sevilla, Spain

(Received November 27, 1989)

Abstract

The Nevado-Filabride Complex and the

overlying Alpujarride and Malaguide Complexes

are the three Alpine terrains which essentially

make up the Alboran crustal domain. It is gener-

ally accepted that during the Early Miocene this

domain occupied a relatively more easterly posi-

tion with respect to Africa and Iberia. The three

complexes formed a nappe-pile (several tens of km

thick) which has since thinned.

The higher Nevado-Filabride nappes at least

have undergone high to-medium P/T ratio meta-

morphism, and several ductile shear zones of vary-

ing thicknesses have been identified in the com-

plex. The stretching lineation ranges between

N50” and 120”E.

The Calar-Alto nappe, the most significant

element of the Nevado-Filabride Complex, moved

across a syn- to post-metamorphic shear zone,

(about 0.5 km thick), resulting in amphibolite

facies overlapping greenschist facies. High-pres-

sure mineral relicts exist in the hanging wall,

whereas they have not been seen in the footwall.

This nappe and the other N-F units initially

formed part of a thinned continental crust,

bounded by transform faults, and would have

represented the southernmost extreme of the

Ligurian Tethys. The emplacement of the N-F

nappes across approximately E-W trajectories is

consistent with the collision subsequent to the

subduction of the Ligurian oceanic crust.

Elsevier Science Publishers B.V.