Blueschists, eclogites, and decompression assemblages of the Zermatt-Saas ophiolite: High-pressure metamorphism of subducted Tethys lithosphere

  title={Blueschists, eclogites, and decompression assemblages of the Zermatt-Saas ophiolite: High-pressure metamorphism of subducted Tethys lithosphere},
  author={Kurt Bucher and Yvonne Fazis and Christian de Capitani and Rodney H. Grapes},
  journal={American Mineralogist},
  pages={821 - 835}
Abstract The Zermatt-Saas ophiolite of the Swiss Alps represents a complete sequence of Mesozoic Tethys oceanic lithosphere. The ophiolite was subducted during early phases of the Alpine orogeny and the mafic rocks were transformed to eclogites and blueschists. Metabasalts locally preserve pillow structures in which glaucophanite forms rims on eclogitic pillow cores. Omphacite-garnet-glaucophane-epidote-ferroan dolomite-Mg-chloritoid-talc-paragonite-chlorite. rutile form characteristic coeval… 
Fluid‐driven transformation of blueschist to vein eclogite during the Early Eocene in a subducted sliver of continental crust (Monte Emilius, Italian Western Alps)
In the Penninic nappe stack of the Western Alps, high‐ to ultrahigh‐pressure metamorphic ophiolites of the Zermatt‐Saas Zone are associated with slivers of continental crust. In one of these slivers,
The Theodul Glacier Unit, a slab of pre-Alpine rocks in the Alpine meta-ophiolite of Zermatt-Saas, Western Alps
The Theodul-Glacier-Unit (TGU) is a 100 m thick and 2 km long slab of pre-Alpine schist, gneiss and mafic rocks tectonically emplaced in the eclogite-facies Zermatt-Saas meta-ophiolite nappe (ZSU).
The Eclogite-facies Allalin Gabbro of the Zermatt–Saas Ophiolite, Western Alps: a Record of Subduction Zone Hydration
The Allalin gabbro is a 2 km � 0� 5 km block of layered olivinegabbro and troctolite included in the Zermatt^Saas ophiolite nappe of the Western Alps. Comprehensive texture, mineral and rock
Dating of ultramafic rocks from the Western Alps ophiolites discloses Late Cretaceous subduction ages in the Zermatt-Saas Zone
Abstract The Zermatt-Saas Zone was part of the Middle to Late Jurassic Tethyan lithosphere that underwent oceanic metamorphism during Mesozoic time and subduction during Eocene time (HP to UHP
Metasediments Covering Ophiolites in the HP Internal Belt of the Western Alps: Review of Tectono-Stratigraphic Successions and Constraints for the Alpine Evolution
Ophiolites of the Alpine belt derive from the closure of the Mesozoic Tethys Ocean that was interposed between the palaeo-Europe and palaeo-Adria continental plates. The Alpine orogeny has intensely
The Antrona ophiolite (western Central Alps) represents a tectonic fragment of the oceanic lithosphere of the Upper Jurassic - Lower Cretaceous Ligurian- Piedmont basin, a section of the Western
Textural Fingerprints of Magmatic, Metamorphic and Sedimentary Rocks Associated with the Naga Hills Ophiolite, Northeast India
The Naga Hills Ophiolite (NHO) in the northern sector of Indo-Myanmar Ranges (IMR) constitutes a long (200 km), narrow (2–15 km wide), NNE-SSW trending, westerly convex sigmoidal belt of
Eclogitization of the Monviso ophiolite (W. Alps) and implications on subduction dynamics
To constrain deep (40–100 km) subduction dynamics, extensive P–T data are provided on the eclogitic Monviso ophiolite derived from the subducted Liguro‐Piemontese oceanic lithosphere (which was
Tectono-Metamorphic Evolution of Serpentinites from Lanzo Valleys Subduction Complex (Piemonte—Sesia-Lanzo Zone Boundary, Western Italian Alps)
In the upper Tesso Valley the folded contact between Piemonte Zone ophiolites and Sesia-Lanzo Zone continental crust is exposed. Here serpentinites, metabasites, calcschists and fine-grained gneisses


High-pressure metamorphism of the Zermatt-Saas ophiolite zone, Switzerland
Within the Zermatt–Saas ophiolite zone of the western Alps a record of polystadial high-pressure metamorphism is well preserved. Early blueschist assemblages, retained as inclusions in garnets, were
Serpentinites of the Zermatt‐Saas ophiolite complex and their texture evolution
The Zermatt‐Saas serpentinite complex is an integral member of the Penninic ophiolites of the Central Alps and represents the mantle part of the oceanic lithosphere of the Tethys. Metamorphic
Jurassic formation and Eocene subduction of the Zermatt–Saas-Fee ophiolites: implications for the geodynamic evolution of the Central and Western Alps
Abstract The Zermatt–Saas-Fee ophiolites (ZSFO) are one of the best preserved slices of eclogitic oceanic crust in the Alpine chain. They formed during the opening of the Mesozoic Tethys and
The formation of eclogite facies metatroctolites and a general petrogenetic grid in Na2O–CaO–FeO–MgO–Al2O3–SiO2–H2O (NCFMASH)
Eclogite facies metatroctolites from a variety of Western Alps localities (Voltri, Monviso, Lanzo, Allalin, Zermat–Saas, etc.) that preserve textural evidence of their original form as bimineralic
‘Forbidden zone’ subduction of sediments to 150 km depth— the reaction of dolomite to magnesite + aragonite in the UHPM metapelites from western Tianshan, China
The solid‐state reaction magnesite (MgCO3) + calcite (aragonite) (CaCO3) = dolomite (CaMg(CO3)2) has been identified in metapelites from western Tianshan, China. Petrological studies show that two