Scheelite Bearing Calc-silicate Gneisses in the Provence Crystalline Basement (var, France)

In the Tanneron massif (north of Cannes) two series of gneisses occur in a basement-cover relationship. The gneiss basement series includes ortho-and paragneisses. The cover series is geochemically related to a shale-greywake sequence with a thick acid volcanic intercalation (leptynite). Swarms of calc-silicate lenses occur sporadically along with marble lenses in the cover and without associated marble in the basement. Scheelite enrichment in the calc-silicate is frequent. The absence of a black shale type environment, the lack of nearby granite, the development of peri-anatectic features (quartzo-feldspathic veins ranging from aplite to pegmatite, local fusion giving birth to small granitoid bodies) and the geochemical characteristics (enrichment in Be, Ta and Eu) suggest that the tungsten mineralization has a peri-anatectic origin.Le massif du Tanneron (au nord de Cannes) est constitué de deux séries de gneiss formant respectivement un socle et sa couverture. Le socle renferme des ortho- et des paragneiss. La couverture, essentiellement paragneissique, peut être rapportée à une série originellement constituée d'une séquence shale-grauwacke avec une intercalation de leptynite (niveau volcanique acide). Des faisceaux de gneiss à silicates calciques associés à des bancs de marbres apparaissent dans la couverture et, sans marbres associés, dans le socle. Des concentrations de scheelite sont fréquentes dans les niveaux calcosilicatés. L'absence d'un environnement de type schistes noirs, l'absence de batholite granitique, le développement de caractéristiques péri-anatectiques (veines quartzo-feldspathiques aplitiques à pegmatitiques, fusion partielle donnant localement des granitoïdes en petits corps) et les caractéristiques géochimiques des horizons minéralisés (enrichissement en Be, Ta et Eu) suggèrent une origine péri-anatectique pour le dépôt de la scheelite.Sonnet Philippe, Verkaeren Jean, Crevola Gilbert. Scheelite bearing calc-silicate gneisses in the Provence crystalline basement (Var, France). In: Bulletin de Minéralogie, volume 108, 3-4, 1985. Minéralogie dans les Sciences de la Terre et l'Industrie - Hommage à François Permingeat

Attention conjointe et apprentissage de mots en co-lecture de livre imprimé vs. numérique chez le jeune enfant

Alors que les livres numériques prennent de plus en plus place dans les interactions parent-enfant, nous ne savons pas si l’attention conjointe et l’acquisition de vocabulaire sont impactées par ce format de livre, comparé au livre imprimé. Nous avons étudié cette question chez 24 enfants de 2 à 3 ans. Nous n’avons pas trouvé de différence : autant l’attention conjointe que l’apprentissage de nouveaux mots étaient similaires en co-lecture de livre imprimé et de livre numérique.As digital books become more and more a part of parent-child interactions, it remains unclear whether joint attention and vocabulary acquisition are impacted by this book format compared to print. We studied this question in 24 children aged 2 to 3 years and found no differences: both joint attention and learning of new words were similar when co-reading print and digital books

Exhumation processes during post-collisional stage in the Variscan belt revealed by detailed 40Ar/39Ar study (Tanneron Massif, SE France)

International audienceDetailed 40Ar/39Ar geochronology on single grains of muscovite was performed in the Variscan Tanneron Massif (SE France) to determine the precise timing of the post-collisional exhumation processes. Thirty-two plateau ages, obtained on metamorphic and magmatic rocks sampled along an east–west transect through the massif, vary from 302 ± 2 to 321 ± 2 Ma, and reveal a heterogeneous exhumation of the lower crust that lasted about 20 Ma during late Carboniferous. In the eastern part of the massif, the closure of the K–Ar isotopic system is at 311–315 Ma, whereas in the middle part of the massif it closes earlier at 317–321 Ma. These cooling paths are likely to be the result of differential exhumation processes of distinct crustal blocks controlled by a major ductile fault, the La Moure fault that separates both domains. In the western part of the massif, the ages decrease from 318 to 303 Ma approaching the Rouet granite, which provides the youngest age at 303.6 ± 1.2 Ma. This age distribution can be explained by the occurrence of a thermal structure spatially associated to the magmatic complex. These ages argue in favour of a cooling of the magmatic body at around 15 Ma after the country rocks in the western Tanneron. The emplacement of the Rouet granite in the core of an antiform is responsible for recrystallization and post-isotopic closure disturbances of the K–Ar chronometer in the muscovite from the host rocks. These new 40Ar/39Ar ages clearly outline that at least two different processes may contribute to the exhumation of the lower crust in the later stage of collision. During the first stage between 320 and 310 Ma, the differential motion of tectonic blocks limited by ductile shear zones controls the post-collisional exhumation. This event could be related to orogen parallel shearing associated with crustal-scale strike-slip faults and regional folding. The final exhumation stages at around 300 Ma take place within the tectonic doming associated to magmatic intrusions in the core of antiformal structures. Local ductile to brittle normal faulting is coeval to Upper Carboniferous intracontinental basins opening

Building sustainable futures: emerging understandings of the significant contribution of the professional learning community

[Abstract]: This article draws on the experiences of a range of Australian schools engaging with a teacher-centred process of whole-school renewal known as IDEAS (Innovative Designs for Enhancing Achievement in Schools). IDEAS enhances the professional capacity of teachers to improve school outcomes such as student learning, relationships with the community, and the coherence of school operation. The article explores how through their engagement with IDEAS, teacher leaders emerge from the professional learning community of the school. After outlining the essential elements of IDEAS, the article explores: how teacher leaders can work collaboratively with administrators to create a contextualized pedagogical framework that transforms their practice; the key concepts of parallel leadership; alignment; and professional conversation. Working with IDEAS, schools create their own futures, supported by their particular pedagogical framework and ways of working. Examples are drawn from particular schools to illustrate the diversity of their experiences and of their learning

Using social knowledge while interacting at the classroom sand center: Facework and cohesion strategies

© The Author(s) 2018In this study, we investigated the ways in which young children used cohesive devices and demonstrated facework to achieve social purposes in their interactions at the sand centre in one kindergarten class. Analyses of video-recordings of five-year old children revealed that children used cohesive strategies, such as referring to objects and people using pronouns, rather than proper nouns. They used repetitions and conjunctions to tie together the ideas from one speaker to the next. Additionally, conversation partners were readily able to construct appropriate meanings from the general references using contextual information. Further, their oral communication demonstrated cooperativeness and engagement as part of their social development. Children used language primarily for imaginative purposes, in addition to communicating information, regulating others’ behavior, and expressing their individuality and emotional responses to activities at the sand centre. They were least likely to use language for interactional purposes. Children’s use of face-work strategies included complimenting peers, softening regulatory language with words, such as “just”, and showing interest in others’ activities.Social Sciences and Humanities Research Counci