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The Veleta and Mulhacen Complexes, previously considered together as the Nevado-Filabride Complex, constitute the deepest units of the Betic Cordilleras. The Veleta Complex (VC) is mainly formed of several thousand metres of graphite-bearing micaschists and crops out as a series of tectonic windows below the Mulhacen Complex (MC). This latter complex comprises a pile of thrust nappes of crustal origin, composed of a Palaeozoic basement and Mesozoic cover series, between which a Jurassic-Cretaceous ophiolitic nappe is tectonically intercalated. The Alpine metamorphism developed in eclogite facies followed by Ab-Ep amphibolite facies in the MC, and in Ab-Ep amphibolite facies followed by greenschist facies in the VC. Pre-Alpine metamorphism in high gradient amphibolite facies is locally well preserved in some basement levels of the MC. In contrast, only scarce relics of pre-Alpine metamorphism, in greenchists facies, have been preserved in the VC. Within the MC nappes of crustal origin there appear metagranitic rocks, which were generated during two stages of late Hercynian magmatic activity: one of syncollisional acidic magmatism and the other of postcollisional intraplate acidic-to-intermediate volcanism. The ophiolitic nappe is composed of basic, ultramafic and sedimentary rocks affected by ocean-floor and orogenic metamorphism. The basic rocks partly retain their original E-MORB geochemical character. The ultramafic rocks are serpentinites and secondary harzburgites containing partly rodingitized basaltic dykes. The Soportujar Formation of the MC is made up of continental and evaporitic metasediments and meta-andesitic rocks that originated during an intraorogenic relaxation period between the eo-Alpine and meso-Alpine metamorphic events.

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The Betic Ophiolitic Association of the Mulhacén Complex, in the Betic Cordilleras of southeastern Spain, is composed, as are other Mesozoic Alpine ophiolitic associations derived from the Western Tethys, of disrupted thrust slices of oceanic crust sandwiched into continental units metamorphosed in a subduction-zone environment. In the Mulhacén Complex, Alpine metamorphism can be subdivided, mainly on the basis of textural relationships supported by geological, paleontological and radiometric data, into two main events: a Late Cretaceous -Paleocene eo-Alpine event, which developed under eclogite-facies conditions, and a Late Eocene -Oligocene meso-Alpine event, under albite-epidote amphibolite-facies conditions. The eo-Alpine event was followed by a retrogression stage, leading to glaucophane-schist-facies assemblages, and the meso-Alpine event climax was followed by greenschist-facies conditions. Metabasic rocks from the Cóbdar and Lugros ophiolitic suites show, respectively, the lowest and the highest grades attained during the eo-Alpine metamorphic event in the Betic Ophiolitic Association of the Mulhacén Complex. The conditions of the metamorphic climax correspond to about 14 kbar and 570°C for the Cóbdar metabasic rocks, i.e., at the limit between glaucophane schists and eclogites, and about 21-22 kbar and 675°C for the Lugros suite, which developed under kyanite-bearing eclogite conditions. Eo-Alpine parageneses were partly obliterated during the meso-Alpine event, the climax of which was about 600 ± 25°C and 8.5 ± 0.5 kbar. SOMMAIRE L'Association Ophiolitique Bétique que montre le complexe de Mulhacén, dans les Cordillères Bétiques du sud-est de l'Espagne, contient, tout comme c'est le cas d'autres suites ophiolitiques alpines mésozoïques dérivées de la marge occidentale de la mer Tethys, des lambeaux de croûte océanique disloqués, insérés dans des unités d'origine continentale métamorphisées dans un milieu de subduction. Dans le complexe de Mulhacén, les effets du métamorphisme alpin peuvent être subdivisés, surtout selon les relations texturales, appuyées par des données géologiques, paléontologiques et radiométriques, en deux événements principaux: le premier, éo-alpin, d'âge crétacé tardif à paléocène, s'est développé aux conditions du faciès éclogite, tans que le second, méso-alpin, d'âge éocène tardif à oligocène, témoigne de conditions typiques du faciès amphibolite à albite-épidote. L'événement éo-alpin a été suivi par un stade de rétrogression menant à des assemblages typiques du faciès des schistes bleus à glaucophane, tandis que des conditions typiques du faciès à schistes verts ont suivi l'événement méso-Alpin. Les roches métabasiques des cortèges ophiolitiques de Cóbdar et de Lugros montrent, respectivement, la plus faible et la plus forte intensité de métamorphisme affectant le complexe de Mulhacén de l'Association Ophiolitique Bétique au cours de l'événement éo-alpin. Les conditions atteintes au cours de cet événement étaient d'environ 14 kbar et 570°C dans la suite de roches métabasiques de §