Thrust sequence and syntectonic sedimentation in a piggy-back basin: the Oligo-Aquitanian Mula–Pliego Basin (Internal Betic Zone, SE Spain)
The Oligo-Aquitanian deposits of the Mula–Pliego basin consist of a marine carbonate platform assemblage (bottom), transitioning into a turbidite wedge (top). This evolution was controlled by tectonics in a piggy-back basin by means of three main mechanisms: first, a flexural tectonic event created the basin; later on, blind-fault-propagation folds deformed it progressively from south to north; finally a tectonic event destroyed the basin. To cite this article: M. Martin-Martin, A. Martin-Algarra, C. R. Geoscience 334 (2002) 363–370.
La estructura del área de Sierra Espuña (contacto zonas internas-externas, sector oriental de la Cordillera Bética)
Sierra Espuna is located in the Eastern Betic Cordillera. The contact between the Malaguide Complex (Internal Betic Zone) and the External Betic Zone cropouts in this area. Sierra Espuna area is a great antiformal stack that is followed by a great synforme (Mula-Pliego Depression). In the upper part of the Malaguide Complex, two nappes, with numerous internal folding and minor thrusting, are recognized: the Morron de Totana Nappe (at the bottom) and the Perona Nappe (at the top). This structure is the result of a complex polyphasic tectonics in which two main structural events are recognized: the Intraoligocene tectonic phase, and the Lower Miocene tectonic phase.
Timing and kinematics of deformation in the Malaguide Complex, internal zone of the Betic Cordillera, southeast Spain
The Betic Cordillera of southern Spain forms the westernmost of the Mediterranean Alpine orogenic belts and is divided, traditionally, into Internal and External Zones. In the External Zone fold and thrust belt, unmetamorphosed cover rocks of the Iberian margin were deformed from the early Miocene onward. In contrast, Internal Zone rocks are dominantly metamorphic and are generally assumed to have been deformed and metamorphosed in an Alpine event resulting from Late Cretaceous/Palaeogene convergence between Africa and Europe. In the Sierra Espuna, at the northern edge of the Internal Zone in the Eastern Betics, the uniquely preserved Permo-Triassic to Miocene stratigraphy of the unmetamorphosed Malaguide Complex, offers a rare opportunity to date the Internal Zone deformation. Kinematic data, thrust geometries and structural facing of folds suggest that the imbricate thrust stack of Malaguide rocks formed as a result of NNW-directed motion, within present geographical coordinates. A fossilized front to this thrust stack, preserved beneath a thick sequence of Oligocene conglomerates, indicates that the timing of the thrust deformation is late Eocene in age. Deformation propagated into the foreland basin in the late Oligocene with renewed thrusting. Subsequently, the whole stack has been folded into a N-NW vergent regional recumbent fold, the Espuna fold, during the early Miocene.