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dated at Neoproterozoic (Bandrés et al., 2004). This mafic- ultramafic ensemble is separated by a ductile mylonitic shear zone, the Trujillanos detachment, from the upper unit. This upper unit is referred to as the Upper Schist-Metagranitoid Unit (Fig. 2), which comprises metabasic to metafelsic igneous rocks intruding a metasedimentary series. The dominant granitoid composition along with the immature nature of the metasedimentary series of this unit suggest continental crust affinity, likely a crustal sec- tion of the Avalonian-Cadomian continental arc (Bandrés et al., 2004). The metasedimentary series described in the upper unit of the Mérida Massif is composed by schists, metagreywackes and black quartzites interlayered with some bodies of fine-grained metaba- sites. This series is identified regionally as equivalent to the lower CARIJA DETACHMENT M A G D A L E N A T H R U S T TR U J I L L A N O S D E T A C H M EN T S C S C S C S C S C S C S C S C 0 2 km H=V ? ? ? ? ? A A’ CADOMIAN FOLIATION (S C ) IGNEOUS CONTACT (INTRUSIVE) CONTACT (NORMAL) THRUST (ALPINE) THRUST (VARISCAN) EXTENSIONAL DETACHMENT (CADOMIAN) THRUST (CADOMIAN) (UNRESOLVEDKINEMATICS) ? (b) AXIAL TRACE OF VARISCAN FOLDS (OVERTURNEDANT-SYNF) (UPRIGHTANT-SYNF) IGNEOUS CONTACT (INTRUSIVE) CONTACT (DISCORDANT) THRUST (ALPINE) THRUST (VARISCAN) EXTENSIONAL DETACHMENT (CADOMIAN) THRUST (CADOMIAN) FAULT (HIGH-ANGLE) AXIAL TRACE OF VARISCAN FOLDS MÉRIDA DonÁlvaro Valverde deMérida SanPedro deMérida Trujillanos SanAndrés Mirandilla 735 740 745 725 730 735 740 745 730 4325 4320 4315 4310 4305 4315 4310 4305 A A’ Variscan Foliation (strike & dip sense) Bedding (strike & dip sense) Cadomian Foliation (strike & dip sense) UPPER SCHIST-METAGRANITOID UNIT MAFIC-ULTRAMAFIC UNIT (MÉRIDA OPHIOLITE) (a) META-GABBROS-DIORITES, PEGMATITIC META- LOWER GNEISS UNIT (MAGDALENA GNEISSES) ORTHOGNEISSES & PARAGNEISSES CARIJADETACHMENT TRUJILLANOSDETACHMENT MAGDALENATHRUST b a Localities VARISCAN MAGMATISM GRANITOIDS COVER (CENOZOIC) CONGLOMERATES, A A’ Cross-section N 0 2 km ETRS89 (Zone 29) UTM Coordinates d c a b e (a) GABBROS,AMPHIBOLITES, GARNET-BEARING AMPHIBOLITES, (b) ULTRAMAFICS & MYLONITES ORDOVICIAN CAMBRIAN (CARIJA UNIT) MARBLES & CALC-SCHISTS (a) META-SANDSTONES, (b) QUARTZITES & SLATES, abcd (c) SLATES & BLACK QUARTZITES, (d) SLATES &QUARTZITES SANDSTONES, SILTS, CLAYS, CALICHE (a)SCHISTS, META-GREYWACKES, BLACK SCHISTS,BLACK Grp, Montemolín Fm.; (e)META- (d)FELSIC (c)META- (b)META-GRANITES (Valverde MIC); QUARTZITES, MINOR META-GABBROS (Don Álvaro MIC) (Valle Real MIC); WITH MINOR META-DIORITES ORTHOGNEISSES (SanAndrés MIC); TONALITES WITH GRANODIORITES AMPHIBOLITES. Serie Negra Fig. 2. (a) Geological map showing the distribution of tectonostratigraphic units in the Mérida Massif (Díez Fernández et al., 2021). (b) Cross-section subparallel to the direction of Cadomian extensional shear zones; it shows the Cadomian nappe pile of the Mérida Massif. (Díez Fernández et al., 2021). E. Rojo-Pérez, U. Linnemann, M. Hofmann et al. Gondwana Research 109 (2022) 89–112 &KDSWHU