Search


 
Issue Title
 
Vol 44, No 2 (2019) Deformation history of ultra high-pressure ophiolitic serpentinites in the Zermatt-Saas Zone, Créton, Upper Valtournanche (Aosta Valley, Western Alps) Abstract  PDF
Pietro Luoni, Davide Zanoni, Gisella Rebay, Maria Iole Spalla
 
Vol 44, No 2 (2019) Lithostratigraphy and petrography of the Monte Banchetta-Punta Rognosa oceanic succession (Troncea and Chisonetto Valleys, Western Alps) Abstract  PDF
Alberto Corno, Pietro Mosca, Alessandro Borghi, Marco Gatteggio
 
Vol 29, No 2 (2004) THE PRE-OROGENIC VOLCANO-SEDIMENTARY COVERS OF THE WESTERN TETHYS OCEANIC BASIN: A REVIEW Abstract  PDF
Gianfranco Principi, Valerio Bortolotti, Marco Chiari, Luciano Cortesogno, Laura Gaggero, Marta Marcucci, Emilio Saccani, Benedetta Treves
 
Vol 32, No 2 (2007) The Versoyen Unit (Western Alps) and its mafic rocks have been long considered the remnants of the oceanic crust that supposedly floored the Valaisan basin during the Cretaceous. Here we present U-Pb dating of zircons from a metaleucogabbro and a metagranite from the Versoyen Unit challenging this view. Magmatic zircon cores yield Permian ages of 267±1 and 272±2 Ma, respectively, which are interpreted as dating the crystallization of the magmas. Older inherited crystals and rare Cretaceous zircon rims (~110-100 Ma) are also present. The young rims are characterized by very high U and REE contents. We speculate that the Cretaceous ages are related to a thermal/fluid event possibly induced by the opening of the Valaisan basin. The proposed Permian age for the Versoyen magmatism, together with the lack of geochronological evidence for a Cretaceous oceanic crust in the Valaisan domain sensu stricto, may force to reconsider the oceanic nature of the Valaisan Basin. We propose a model in which the Versoyen Unit is unrelated to and pre-dates the extensional tectonics that led to the formation of the Valaisan Basin and the Cretaceous deposition of sediments on this Permian basement. The Permian ages for the Versoyen intrusives correlate with extensive Permian intra-plate magmatism related to lithospheric stretching prior to the break-up of Pangea. The Versoyen Unit becomes the most external Alpine terrane that displays traces of this Permian basic magmatism. Traces of Cretaceous magmatism are preserved in the more internal Chiavenna and Balma units, located in the Central and Western Alps, respectively. However, several lines of evidence suggest that such units may have been unrelated to the Valaisan Basin. Therefore, we propose a new palaeogeographic scenario for the western Tethys, where two independent basins, the Valaisan Basin and the Chiavenna/Balma Ocean, were located between the Briançonnais micro-Plate and the European Plate sensu stricto.  PDF
Marco Beltrando, Daniela Rubatto, Roberto Compagnoni, Gordon Lister
 
Vol 32, No 1 (2007) THE PLAGIOGRANITE - FeTi-OXIDE GABBRO ASSOCIATION OF VERNE (MONVISO METAMORPHIC OPHIOLITE, WESTERN ALPS) Abstract  PDF
Daniele Castelli, Bruno Lombardo
 
Vol 30, No 2 (2005) STRUCTURAL AND COMPOSITIONAL FEATURES OF THE MT. MUSINÈ PERIDOTITES (LANZO MASSIF, WESTERN ALPS, ITALY) Abstract  PDF
Franco M. Elter, Giovanni B. Piccardo, Riccardo Polino, Alberto Zanetti, Gianluca Spagnolo, Eugenio Poggi, Pietro Balbi
 
Vol 30, No 2 (2005) RECENT RESEARCHES ON MELT-ROCK INTERACTION IN THE LANZO SOUTH PERIDOTITE Abstract  PDF
Giovanni B. Piccardo, Alberto Zanetti, Gianluca Spagnolo, Eugenio Poggi
 
Vol 30, No 2 (2005) EXHUMATION OF MANTLE LITHOSPHERE: FIELD RELATIONS, AND INTERACTION PROCESSES BETWEEN MAGMATISM AND DEFORMATION (FIELD TRIP TO THE NORTHERN LANZO PERIDOTITE) Abstract  PDF
Mary-Alix Kaczmarek, Othmar Müntener
 
Vol 30, No 2 (2005) REVISITING THE LANZO PERIDOTITE (NW-ITALY): ‘ASTHENOSPHERIZATION’ OF ANCIENT MANTLE LITHOSPHERE Abstract  PDF
Othmar Müntener, Giovanni B. Piccardo, Riccardo Polino, Alberto Zanetti
 
Vol 41, No 2 (2016) QUARTZ FABRIC VARIATIONS ACROSS THE GREENSCHIST FACIES SHEAR ZONE SEPARATING THE ZERMATT-SAAS AND COMBIN OPHIOLITIC ZONES, UPPER VAL GRESSONEY, WESTERN ALPS Abstract  PDF
Elisa Savignano, Steven M. Reddy, Jed Bridges, Stefano Mazzoli
 
Vol 37, No 1 (2012) ECLOGITE-FACIES SEA-FLOOR HYDROTHERMALLY-ALTERED ROCKS: CALCULATED PHASE EQUILIBRIA FOR AN EXAMPLE FROM THEWESTERN ALPS AT SERVETTE Abstract  PDF
Gisella Rebay, Roger Powell
 
Vol 33, No 2 (2008) EVOLUTION OF RODINGITIC DYKES: METASOMATISM AND METAMORPHISM IN THE MOUNT AVIC SERPENTINITES (ALPINE OPHIOLITES, SOUTHERN AOSTA VALLEY) Abstract  PDF
Matteo Panseri, Emanuele Fontana, Paola Tartarotti
 
Vol 29, No 1 (2004) THE LANZO SOUTH PERIDOTITE: MELT/PERIDOTITE INTERACTION IN THE MANTLE LITHOSPHERE OF THE JURASSIC LIGURIAN TETHYS Abstract  PDF
Giovanni B. Piccardo, Othmar Müntener, Alberto Zanetti, Anna Romairone, Stefano Bruzzone, Eugenio Poggi, Gianluca Spagnolo
 
Vol 33, No 2 (2008) OCEANIC RELICT TEXTURES IN THE MOUNT AVIC SERPENTINITES, WESTERN ALPS Abstract  PDF
Emanuele Fontana, Matteo Panseri, Paola Tartarotti
 
Vol 28, No 1 (2003) LITHOSTRATIGRAPHY AND STRUCTURE OF THE LAGO NERO UNIT (CHENAILLET MASSIF, WESTERN ALPS): COMPARISON WITH INTERNAL LIGURIDE UNITS OF NORTHERN APENNINES Abstract  PDF
Alessandro Burroni, Nicola Levi, Michele Marroni, Luca Pandolfi
 
Vol 33, No 1 (2008) AN ECLOGITISED OCEANIC PALAEO-HYDROTHERMAL FIELD FROM THE ST. MARCEL VALLEY (ITALIAN WESTERN ALPS) Abstract  PDF
Silvana Martin, Gisella Rebay, Jean-Robert Kienast, Catherine Mével
 
Vol 27, No 2 (2002) ION MICROPROBE U-PB DATING OF ZIRCON FROM A MONVISO METAPLAGIOGRANITE: IMPLICATIONS FOR THE EVOLUTION OF THE PIEDMONT-LIGURIA TETHYS IN THE WESTERN ALPS Abstract  PDF
Bruno Lombardo, Daniela Rubatto, Daniele Castelli
 
Vol 27, No 2 (2002) JD-QTZ-BEARING METAPLAGIOGRANITE FROM THE MONVISO META-OPHIOLITE (WESTERN ALPS) Abstract  PDF
Daniele Castelli, Claudia Rostagno, Bruno Lombardo
 
1 - 18 of 18 Items

Search tips:

  • Search terms are case-insensitive
  • Common words are ignored
  • By default only articles containing all terms in the query are returned (i.e., AND is implied)
  • Combine multiple words with OR to find articles containing either term; e.g., education OR research
  • Use parentheses to create more complex queries; e.g., archive ((journal OR conference) NOT theses)
  • Search for an exact phrase by putting it in quotes; e.g., "open access publishing"
  • Exclude a word by prefixing it with - or NOT; e.g. online -politics or online NOT politics
  • Use * in a term as a wildcard to match any sequence of characters; e.g., soci* morality would match documents containing "sociological" or "societal"