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International audience; The Seixoso-Vieiros Rare Element Pegmatite fined by Farias et al (1987). The Seixoso-Vieiros pegmatite field is known for containing numerous granitic pegmatite-aplite veins (Seixoso and Vieiros pegmatites). The area is bounded at the north by the Variscan Celorico de Basto granite massif. On the SE it is bounded by the syn-tectonic Felgueiras granodiorite. Several pegmatites outcrop within cordierite-andalusite isograde Silurian schists. The field is also known for mining of cassiterite and columbite-tantalite in the last century (Maijer, 1965). In the Seixoso area, an unusual heterogeneous granitic intrusion outcrops as two main apices in Seixoso and Outeiro as granites cupolas (Lima et al., 2009). These rocks show a typical granitic mineral assemblage and exhibit a textural variation from biotite-bearing, at depth, to two mica, or muscovite tourmaline, near the apex roof (Helal et al., 1993). The Seixoso granite is described as a fine to medium-grain leucogranite, with biotite and muscovite, strongly altered with albitization and greisenization close to the contact zones. The Outeiro granite is layered and shows pegmatitic segregations. In the latter, Li-bearing minerals, such as petalite and spodumene, have been observed. In addition, minerals from the amblygonite-montebrasite series have also been noted within the granitic mineral assemblage (Lima et al., 2009). Other notable accessory minerals include: beryl, chrysoberyl, tourmaline and sekaninaite, and others. In the Vieiros area, the granitic aplite-pegmatite veins mainly cross-cut schists of Silurian age within the andalusite isograde. A dozen N-S to NE-SW-trending Sn-bearing granitic aplite-pegmatite veins outcrop in the area. They present a rich mineralogy: quartz, K-feldspar, albite, muscovite, petalite, spodumene, amblygonite-montebrasite, cassiterite, columbite-tantalite, tourmaline, and many different sulfides. An albite type pegmatite is exposed in the Vieiros mine and measures 300 meters in length, an average 5 meters in width, and is subvertical, striking E-W, and dips N25°. During this study (Melleton et al., submitted), columbite and tantalite grains were dated by the U-Pb method, using the LA-SF-ICP-MS technique, from the Outeiro mine granite and the Vieiros mine albite type pegmatite. Results of dating (figure 1) from the Vieiros pegmatite yield an age of emplacement of 301 ± 4 Ma (12 analyses). Ages obtained from the Outeiro granite yield 301 ± 5 Ma (9 analyses) and 316 ± 9 Ma (from two analyses located in cores of two different single grains, and with significantly low concentrations of U). This latter age is interpreted as age of crystallization of the Outeiro granite, and the younger age corresponds to post-emplacement disturbance related to the Vieiros-Seixoso pegmatite emplacement, located in the surrounding area. Located hundred meters from the Outeiro mine granite, the Seixoso pegmatite shows similar structural and mineralogical features as the Vieiros pegmatite. Therefore, emplacement of these pegmatites and associated fluids could have been the cause of the Outeiro Mine columbite-tantalite rim age. The Celorico de Basto late-D3 granite in the north and the Felgueiras syn-D3 granodiorite in the south had not been directly dated. However, Dias et al. (1998) dated equivalent granitoids and obtained ages around 305-308 Ma for the late D3 granite and early ages ranging between 310 and 320 Ma for the syn-D3 granites. Thus, there is not a temporal link between the Vieiros pegmatite emplacement and the surrounding granites of this field. New samples are being collected in order to understand the different mineralizing events and relationships between other pegmatites and surrounding granitic cupolas of the studied area.

WEGENER is originally the acronym for Working Group of European Geoscientists for the Establishment of Networks for Earth-science Research. It was founded in March 1981 in response to an appeal delivered at the Journées Luxembourgeoises de Geodynamique in December 1980 to respond with a coordinated European proposal to a NASA Announcement of Opportunity inviting participation in the Crustal Dynamics and Earthquake Research Program. WEGENER, during the past 32 years, has always kept a close contact with the Agencies and Institutions responsible for the development and maintenance of the global space geodetic networks with the aim to make them aware of the scientific needs and outcomes of the project which might have an influence on the general science policy trends. WEGENER was serving as Inter-commission Project 3.2, between Commission 1 and Commission 3, of the International Association of Geodesy (IAG) until 2012. Since then, WEGENER project has became the Sub-commission 3.5 of IAG commission 3, namely Tectonics and Earthquake Geodesy. In this study, we briefly review the accomplishments of WEGENER as originally conceived and outline and justify the new focus of the WEGENER consortium. The remarkable and rapid evolution of the present state of global geodetic monitoring in regard to the precision of positioning capabilities (and hence deformation) and global coverage, the development of InSAR for monitoring strain with unprecedented spatial resolution, and continuing and planned data from highly precise satellite gravity and altimetry missions, encourage us to shift principal attention from mainly monitoring capabilities by a combination of space and terrestrial geodetic techniques to applying existing observational methodologies to the critical geophysical phenomena that threaten our planet and society. Our new focus includes developing an improved physical basis to mitigate earthquake, tsunami, and volcanic risks, and the effects of natural and anthropogenic climate change (sea level, ice degradation). In addition, expanded applications of space geodesy to atmospheric studies will remain a major focus with emphasis on ionospheric and tropospheric monitoring to support forecasting extreme events. Towards these ends, we will encourage and foster interdisciplinary, integrated initiatives to develop a range of case studies for these critical problems. Geological studies are needed to extend geodetic deformation studies to geologic time scales, and new modeling approaches will facilitate full exploitation of expanding geodetic databases. In light of this new focus, the WEGENER acronym now represents, “World Earthquake GEodesy Network for Environmental Hazard Research”.