Using high-resolution ammonite biochronostratigraphy to date volcanogenic deposits preserved in middle Jurassic carbonate platforms successions of the westernmost tethys (southeastern iberian range, spain)
The Middle Jurassic successions that are currently exposed in eastern Spain (southeastern Iberian Range) were deposited in a system of shallow carbonate platforms, constituting the western margin of the Alpine Ocean, and display a series of successively interbedded volcaniclastic rocks and minor lav...
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2021 |
| País: | España |
| Institución: | Universidad Complutense de Madrid (UCM) |
| Repositorio: | Docta Complutense |
| Idioma: | inglés |
| OAI Identifier: | oai:docta.ucm.es:20.500.14352/8574 |
| Acceso en línea: | https://hdl.handle.net/20.500.14352/8574 |
| Access Level: | acceso abierto |
| Palabra clave: | 551.762(460) ammonite associations biochronostratigraphy Jurassic Alpine Ocean intracontinental volcanism Geología estratigráfica Paleontología 2506.19 Estratigrafía 2416 Paleontología |
| Sumario: | The Middle Jurassic successions that are currently exposed in eastern Spain (southeastern Iberian Range) were deposited in a system of shallow carbonate platforms, constituting the western margin of the Alpine Ocean, and display a series of successively interbedded volcaniclastic rocks and minor lava flows. The large-scale mapping reveals that Middle Jurassic volcanic rocks crop out along NW‒SE pathways, highlighting the importance of the role played by tectonics in controlling the spatial distribution of volcanic outcrops. The progressive dismemberment of Pangea impelled a geographic provinciality increase and, thus, might have contributed to a growing speciation rate of marine invertebrate organisms, notably ammonites. The present study provides new data constraining in detail the age of the Middle Jurassic volcanic deposits. The biochronostratigraphic calibrations of the sedimentary host rocks encasing the volcanics have been obtained from the study of the fossil content (mainly ammonites) from16 well-exposed stratigraphic sections. The study of the fossils from these sections has enabled the identification of three volcanic episodes during the Murchisonae Zone (Aalenian), the Concavum‒Discites zonal boundary (Aalenian-Bajocian), and the late Laeviuscula Zone or Laeviuscula‒Propinquans zonal boundary (Bajocian). Precise age constraints for volcanic accumulations can be a significant contribution in reconstructing the geodynamic history of the Iberian Basin. |
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