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[EN]A detailed geochronological study was conducted on zircons from a diorite sample of the Posets pluton (Axial Zone, Pyrenees). The extracted igneous zircons constrain the emplacement of the pluton to 302 +/- 2 Ma and 301 +/- 3 Ma, by means of U-Pb sensitive high-resolution ion microprobe (SHRIMP) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses, respectively. Considering the syn- to late-tectonic emplacement of the Posets pluton during the main Variscan deformation event (D-2), the obtained ages constrain the long-lasting D-2, associated with the dextral transpression registered through the Axial Zone of the Pyrenees. This work was supported by grants EHUA13/03 and GIU20/017 from the University of the Basque Country (UPV/EHU) and CGL2017-82976 from the Ministerio de Economia, Industria y Competitividad / Agencia Estatal de Investigacion / Fondo Europeo de Desarrollo Regional, European Union. E. Druguet, Y. Denele, an anonymous reviewer and the editor Olivier Lacombe are thanked for reviews and discussions that improved the final manuscript.

Photography is an important instrument in tourism marketing, which aims to encourage consumption and consolidate the image of a tourist destination in consumers’ minds. The elements of geodiversity with aesthetic and cultural values are commonly used as differentiated products in tourism destinations. This article discusses the relation between geodiversity, tourism marketing and the use of photographs in consolidating the image of a destination, focusing on those based in geotourism practices. The case study analyzes photographs from tourism promotion materials of the Basque Coast UNESCO Global Geopark (Spain), seeking to understand the techniques, fieldwork, symbols and narratives present therein. The methodology involves a theoretical discussion, field work and a qualitative description of the photographs with physical attributes. Geological and geomorphological features of Basque Coast are shown in photographs, highlighting a singular geoheritage that sustains environmental and cultural conservation, a principle that every geopark should construct and transmit.

Detailed petrographic and geochemical studies conducted on zircons from the Lys-Caillaouas pluton reveal their igneous and metamorphic affinities. The igneous zircons constrain the emplacement of the pluton to 300±2 Ma. By contrast, the metamorphic zircons yield an older age of 307±3 Ma, which probably dates the thermal peak of the HT/LP Variscan metamorphism. Therefore, a short time lag of c. 7 Ma emerges between the metamorphic climax and emplacement of the pluton in the Axial Zone (Pyrenees).

The International Commission on Stratigraphy (ICS) formally approves the chronostratigraphic units of the International Chronostratigraphic Chart that serve as the basis of the Geologic Time Scale. An essential part of this process is the definition of a Global Stratotype Section and Point (GSSP) that defines the lower boundary of each chronostratigraphic unit of Stage, Series, System, Erathem, and Eonthem rank. Once approved by the ICS and ratified by the International Union of Geological Sciences, each GSSP is an international geostandard, and it is marked and dedicated. It is imperative that GSSPs, once ratified, are preserved, protected and maintained for the purpose of future scientific study. Furthermore, each GSSP can serve as a local focal point of educational outreach that educates the public on the nature of the stratigraphic record and the marvels it reveals about Earth’s history. Preservation, protection, maintenance and education are best accomplished when a GSSP is located in a nature preserve as exemplified by the two GSSPs located in the Basque Coast UNESCO Global Geopark on the north coast of Spain.

The global stratotype sections and points for the bases of the Selandian (Middle Paleocene) and Thanetian (Upper Paleocene) stages have been defined in the coastal cliff along the ltzurun Beach at the town of Zumaia in the Basque Country, northern Spain. In the hemipelagic section exposed at Zumaia the base of the Selandian Stage has been placed at the base of the ltzurun Formation, ca. 49 m above the Cretaceous/ Paleogene boundary. At the base of the Selandian, marls replace the succession of Danian red limestone and limestone-marl couplets. The best marine, global correlation criterion for the basal Selandian is the second radiation of the important calcareous nannofossil group, the fasciculiths. Species such as Fasciculithus ulii, F. billii, F. janii, F. involutus, F. pileatus and F. tympaniformis have their first appearance in the interval from a few decimetres below up to 1.1 m above the base of the Selandian. The marker species for nannofossil Zone NP5, F. tympaniformis, first occurs 1.1 m above the base. Excellent cyclostratigraphy and magnetostratigraphy in the section creates further correlation potential, with the base of the Selandian occuring 30 precession cycles (630 kyr) above the top of magnetochron C27n. Profound changes in sedimentology related to a major sea-level fall characterize the Danian-Selandian transition in sections along the margins of the North Atlantic. The base of the Thanetian Stage is placed in the same section ca. 78 m above the Cretaceous/Paleogene boundary. It is defined at a level 2.8 m or eight precession cycles above the base of the core of the distinct clay-rich interval associated with the Mid-Paleocene Biotic Event, and it corresponds to the base of magnetochron C26n in the section. The base of the Thanetian is not associated with any significant change in marine micro-fauna or flora. The calcareous nannofossil Zone NP6, marked by the first occurrence of Heliolithus kleinpelli starts ca. 6.5 m below the base of the Thanetian. The definitions of the global stratotype points for the bases of the Selandian and Thanetian stages are in good agreements with the definitions in the historical stratotype sections in Denmark and England, respectively. Open access journal ispartof: Episodes: International Geoscience Newsmagazine vol:34 issue:4 pages:220-243 status: published