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El proyecto Geosites, en desarrollo por el grupo de trabajo Global Geosites de la IUGS y patrocinado también por la UNESCO, persigue la elaboración de un inventario global del patrimonio geológico de la Tierra. Este inventario global requiere una metodología sistemática, basada en la selección en cada país de sus contextos geológicos de trascendencia internacional. Estos contextos geológicos o frameworks consisten en eventos temáticos, o en elementos cronológicos o geotectónicos regionales. El segundo paso en esta metodología es la selección de los lugares más valiosos y representativos de estos contextos geológicos, denominados geosites (geotopos o lugares de interés geológico). Afortunadamente la diversidad geológica española suministra un gran número de contextos geológicos con relevancia internacional; además la buena calidad de los afloramientos (debida a causas climáticas y topográficas) permitirá la selección de geotopos ilustrativos. En esta comunicación se presenta un listado de los contextos geológicos españoles elaborado por consenso. Se ha preparado siguiendo la metodología del Proyecto Geosites sin tener en cuenta el Inventario Nacional de Puntos de Interés Geológico que está en ejecución y cubre alrededor del 40% del territorio español. El IGME preparó una lista preliminar que fue enviada a todos los departamentos universitarios de Ciencias Geológicas, Minas y centros públicos de investigación, para su análisis, discusión y mejora. Como resultado de esta encuesta se han seleccionado 20 frameworks o contextos geológicos que constituyen la primera aportación española al proyecto Geosites., The Geosites project, initiated by the IUGS Global Geosites Working Group and also supported by UNESCO, aims to produce a global inventory of the Earth’s geological heritage. This global inventory requires a systematic methodology, which is based on the selection of geological frameworks with international significance, in every country. These frameworks are topic events, time or regional geotectonic elements, etc. The second step of this methodology is the selection of the most valuable and representative sites of these geological frameworks (geosites). Fortunately, the geological diversity of Spain provides a great number of frameworks with global significance; in addition, the high quality of outcrops (due to topographic and climatic reasons) will allow the selection of illustrative geosites. In this paper a list of Spanish geological frameworks set by consensus is presented. It was prepared following the Geosites Project methodology without taking into account the National Inventory of Geosites, which is in progress and covers a 40% of the Spanish territory. The IGME (Geological Survey of Spain) composed a preliminarg list, which was sent to all the University Departaments of Geology, Mining Schools and Research Centers, for its analysis, discussion and improvement. The result of this request was the selection of 20 “frameworks”, which is the first Spanish contribution to the Geosites Project., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

[EN] An integrated study including magnetostratigraphy, larger benthic foraminifera and calcareous nannofossil biostratigraphy is presented herein. This work was performed in shallow marine siliciclastics rich in larger foraminifera, around the Ypresian/Lutetian boundary in the Ésera valley (South-Central Pyrenees). Although the calcareous nannofossil content in the studied interval is low, not allowing a precise Y/L boundary to be recognised, the taxa found are enough to support the chronostratigraphic attribution. Data obtained in the Ésera valley section has improved the knowledge of larger benthic foraminifera (Nummulites and Assilina) distribution through chron C21. SBZ 11 to SBZ 12 transition took place at the lowermost C21r, as shown in previous works. SBZ 12 assemblages extend into C21n, where the SBZ 12 to SBZ 13 boundary occurs. These data, obtained in shallow marine siliciclastic facies, with in situ fauna, results in a shift of the SBZ 12/SBZ 13 boundary to the Lower Lutetian, younger than previously believed. Accordingly, the Ypresian/Lutetian boundary occurs in SBZ 12.

[EN] Despite the large number of magnetostratigraphic studies in the South Pyrenean Basin aiming to calibrate the basin chronostratigraphy and the biostratigraphic scales, the South Eastern Jaca Basin remains unexplored from this perspective, and its relation with the Ainsa Basin is not fully understood. In this work we contribute with new magnetostratigraphic data from the 950m thick Las Bellostas section, located in the northern hinge of the Balzes anticline. Well-proven primary signal (positive fold test and two pseudo-antiparallel polarities) supported by numerous primary data in the surroundings allow us building a reliable local polarity sequence of eight magnetozones (from R1 to N4). Additionally, seven new biostratigraphic samples (Nummulites and Assilina) in the lower part of the section (marine environment) allows tightening the section to the Geomagnetic Polarity Time Scale (GPTS) and proposing a refined age model for the southeastern Jaca Basin. The section starts in the Boltaña Fm., of Cuisian age (Shallow Benthic Zone, SBZ11), is followed by a sedimentary gap from C22n to C20n as witnessed by biostratigraphic data (SBZ11 underneath the hiatus and SBZ16 just atop). The deltaic Sobrarbe Fm can be tracked until the C19n (Late Lutetian). From this point (200m) until the top of the section (950m), at least, the entire C18n chron can be recognized within the molassic Campodarbe Fm (C18n.2n-C18n.1r and C18n.1n) (Bartonian) equivalent to the West to the prodeltaic Arguis marls Fm. The Middle Cusian (SBZ11) to Middle Lutetian (SBZ15) stratigraphic hiatus is, in part, enhanced by the structural position at the hinge of the Balzes anticline. These new chronostratigraphic constraints help refining the W-E and N-S stratigraphic relationships in the eastern Jaca Basin and in the Ainsa Basin. This section also allows us to accurately refine the kinematics of the rotational activity in the eastern External Sierras. The important difference in magnetic declination alon

CRUE-CSIC (Acuerdos Transformativos 2022), The record of brachiopods in the Lower Toarcian of the Balearic Islands is described after a reassessment of previous works and new samplings in the Tramuntana Range of Mallorca. The recognized species have been assimilated to the assemblages described in the Iberian Range in the Tenuicostatum and Serpentinum biozones. Moreover, a detailed comparison with other Western Tethys basins and the study of the dispersion of the brachiopod faunas in relation with the Early Toarcian Oceanic Anoxic Event, allow to refine the paleobiogeographic relationship of the Balearic brachiopods. They belong to the Euro-Boreal Province of brachiopods in the Tenuicostatum Biochron and correspond to the”Spanish Fauna” that emerged after the deep paleobiogeographic disruption that took place at the base of Serpentinum Biochron. The occurrence of Prionorhynchia msougari Rousselle in the Serpentinum Zone of Mallorca indicates that, within this last assemblage, there would be a closer connection between the Balearic region and the southern margin of the Tethys (Betic and North African basins) than with the northern margin (Eastern Iberian Platform System and Eastern Pyrenees). This paleobiogeographic conclusion is consistent with the supposed position of the Balearic area in the Early Toarcian, on the southeastern margin of Iberia and near the Alboran and Kabylian margins., Ministerio de Ciencia e Innovación (MICINN), Universidad Complutense de Madrid, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub