Cresta, S.Goy Goy, AntonioUreta Gil, María SoledadArias Fernández, María Del CarmenBarrón López, EduardoBernard García, JulioCanales Fernández, María LuisaGarcía Joral, FernandoGarcía Romero, EmiliaGialanella, P.R.Gómez Fernández, Juan JoséGonzález, J.A.Herrero Matesanz, M. De La ConcepciónMartínez Gutiérrez, GemmaOsete López, María LuisaPerilli, NicolaVillalaín, J.J.2023-06-202023-06-2020010705-3797https://hdl.handle.net/20.500.14352/57584The Global Boundary Stratotype Section and Point (GSSP) for the Aalenian Stage, formally defined at the base of bed FZ107 in the Fuentelsaz section, Castilian Branch of the Iberian Range (Spain), has been ratified by the IUGS. Multidisciplinary biostratigraphical data, based on ammonites, brachiopods, ostracods, bivalves, foraminifera, calcareous nannofossils assemblages and palynomorphs, assure worldwide correlations; magnetostratigraphic data increase this correlation power. The position of the boundary coincides with the first occurrence of the ammonite assemblage characterized by Leioceras opalinum and Leioceras lineatum and corresponds with a normal polarity interval correlated with the up-to-date Jurassic magnetic polarity time scale (Gradstein and others, 1994; Ogg, 1995).engjournal articlehttp://www.episodes.co.in/open access551.762Toarcian-Aalenian BoundaryLower-Middle JurassicGeología estratigráfica2506.19 Estratigrafía