Inoceramid constraints on the timing of Sant Corneli anticline uplift (Tremp Basin, South-Central Pyrenees, NE Spain)

The Sant Corneli Anticline is an asymmetric, westward-plunging structure located at the termination of the Boixols Thrust (Tremp Basin, Spanish Pyrenees). It was emplaced during the Late Cretaceous and generated an elongated, westward-deepening foredeep basin. A stratigraphic and palaeontological st...

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Detalles Bibliográficos
Autores: Mercedes-Martín, Ramon|||0000-0002-4410-1984, Walaszczyk, Ireneusz
Tipo de recurso: artículo
Fecha de publicación:2026
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:dnet:uabarcelona_::7318275b62416605f9b50840d16f6aff
Acceso en línea:https://ddd.uab.cat/record/328558
https://dx.doi.org/urn:doi:10.1344/GeologicaActa2026.24.6
Access Level:acceso abierto
Palabra clave:Inoceramids
Paleontology
Biostratigraphy
Tremp basin
Pyrenees
Cretaceous
Descripción
Sumario:The Sant Corneli Anticline is an asymmetric, westward-plunging structure located at the termination of the Boixols Thrust (Tremp Basin, Spanish Pyrenees). It was emplaced during the Late Cretaceous and generated an elongated, westward-deepening foredeep basin. A stratigraphic and palaeontological study of inoceramid bivalves from the southern flank of the Sant Corneli Anticline provides refined constraints on the timing and lateral distribution of synorogenic carbonate-marly units (growth strata) that predate the emplacement of mixed depositional systems during anticline uplift. Two stratigraphic units were identified and dated based on inoceramid biostratigraphy: the upper Podega Member (marly limestones with slump structures) and the Montesquiu Member (alternating limestones and marls). The upper Podega Member can be traced laterally southwest of the Sant Corneli Anticline, with thickness decreasing from approximately 230 m in the west to 170 m in the east. This unit exhibits meter- to decameter-scale soft-sediment deformation structures and syn-sedimentary faults, indicating gravitational collapse processes. Biostratigraphically, it spans from the upper Santonian to the basal upper Campanian (European bipartite subdivision). The overlying Montesquiu Member shows a similar west-to-east thinning trend, decreasing from about 226 m to 150 m. It is characterized by frequent intraformational unconformities and widespread soft-sediment deformation at meter- to decameter scale, reflecting active tectonism during deposition. Based on inoceramid assemblages, this unit is assigned to the middle-upper Campanian. It predates the development of shallower mixed depositional systems, which are only marginally affected by soft-sediment deformation structures.