RT Journal Article
T1 Tectonic Evolution of the Careón Ophiolite (Northwest Spain):A Remnant of Oceanic Lithosphere in the Variscan Belt
A1 Díaz García, Florentino
A1 Arenas Martín, Ricardo
A1 Martínez Catalán, José Ramón
A1 González del Tánago, José
A1 Dunning, Gregory R.
AB Analysis of the Careoó Unit in the Ordenes Complex (northwest Iberian Massif) has supplied relevant data concerningthe existence of a Paleozoic oceanic lithosphere, probably related to the Rheic realm, and the early subduction-relatedevents that were obscured along much of the Variscan belt by subsequent collision tectonics. The ophiolite consistsof serpentinized harzburgite and dunite in the lower section and a crustal section made up of coarse-grained andpegmatitic gabbros. An Early Devonian zircon age (395±2 Ma, U-Pb) was obtained in a leucocratic gabbro. Thewhole section was intruded by numerous diabasic gabbro dikes. Convergence processes took place shortly afterward,giving rise to a mantle-rooted synthetic thrust system, with some coeval igneous activity. Garnet amphibolite,developed in metamorphic soles, was found discontinuously attached to the thrust fault. The soles graded downwardto epidote-amphibolite facies metabasite and were partially retrogressed to greenschist facies conditions. Thermobarometricestimations carried out at a metamorphic sole (T ≈ 650ºC; P ≈ 11.5 kbar) suggested that imbricationsdeveloped in a subduction setting, and regional geology places this subduction in the context of an early Variscanaccretionary wedge. Subduction and imbrication of oceanic lithosphere was followed by underthrusting of the Gondwanacontinental margin.
PB University of Chigaco Press
SN 0022-1376
YR 1999
FD 1999
LK https://hdl.handle.net/20.500.14352/57758
UL https://hdl.handle.net/20.500.14352/57758
LA eng
DS Docta Complutense
RD 8 abr 2025