Abstract Records of Variscan structural and metamorphic imprints in the Alps indicate that before Pangaea fragmentation, continental lithosphere was thermally mechanically perturbed during subduction collision. A diffuse igneous activity associated with high-temperature (HT) metamorphism, accounting for a Permian–Triassic high thermal regime, is peculiar to Alpine area has been interpreted as induced either by late-orogenic collapse or lithospheric extension thinning leading rifting....

Abstract Petrological investigations supported by multi‐scale structural analysis of eclogitized serpentinite in the Zermatt–Saas Zone Western Alps allows for determination mineral assemblages related to successive fabrics, upon which P–T–d–t path these hydrated mantle rocks can be inferred. Serpentinites upper Valtournanche, with lenses and dykes metagabbro meta‐rodingite, display an Alpine polyphase metamorphic evolution from eclogite epidote‐amphibolite facies conditions associated three...

The Red Sea and Gulf of Aden represent two young basins that formed between Africa Arabia since the early Oligocene, floored by oceanic crust or transitional thinned continental crust.While in easternmost Aden, rift-drift transition can be dated chron C6 (∼20.1 Ma), here we show first pulse seafloor spreading occurred during C3n.2n (∼4.6 Ma) around ∼17.1 • N (present-day coordinates) propagated southwards from this location, separating Danakil microplate Arabia.It is also shown Nubia started...

Abstract Multiscale structural analysis and petrological modelling were used to establish the pressure‐peak mineral assemblages pressure–temperature ( P–T ) conditions recorded in rodingites of upper Valtournanche portion oceanic Zermatt‐Saas Zone (ZSZ; Western Alps, northwestern Italy) during Alpine subduction. Rodingites occur form deformed dykes boudins within hosting serpentinites. A field showed that serpentinites record four ductile deformation stages (D1–D4) cycle, with first three...

In the Alps, numerous mafic, ultramafic, and sedimentary protoliths have been affected by Variscan metamorphism due to processes including subduction, collision, late-orogenic extension, persisting until Early Permian times. eclogites derived from oceanic lithosphere are extensively documented, particularly in External Crystalline Massifs (EMC) of Western Alps (Helvetic-Dauphinois-Provençal domain). These typically found as lenses boudins enclosed within migmatitic gneiss offer...

Within the Zermatt-Saas Zone (Western Alps), Riffelberg-Garten Unit is part of ophiolite meta-sedimentary cover, which in uppermost Valtournanche contains metabasite (some with gabbro texture) and minor ultramafite elements. Seven types are distinguished based on rock matrix composition amount, shape, composition, size enclosed The varies between carbonate-rich quartz-rich, white mica most types. These rocks record four groups Alpine syn-metamorphic ductile structures. first two, developed...

Abstract The Zermatt-Saas Zone was part of the Middle to Late Jurassic Tethyan lithosphere that underwent oceanic metamorphism during Mesozoic time and subduction Eocene (HP UHP metamorphism). In upper Valtournanche, serpentinite, metarodingite eclogite record a dominant S2 foliation developed under 2.5±0.3 GPa 600±20°C Alpine subduction. Serpentinites contain clinopyroxene rare zircon porphyroclasts. Clinopyroxene porphyroclasts show fringes within with similar compositions grains defining...

Since the beginning of last century, tectonic history polyphase metamorphic tectonites orogenic basement complexes is often related to primary links with metasediments, presumably known origin, and location their original basins. However such worth be compared results an alternative, independent investigation that pursues: i) objective reconstruction evolutionary steps modifying lithostratigraphic setting its deformation-metamorphism interactions during plate-scale events, ii) a privileged...

The ∼30 Ma Biella and Traversella late-collisional intermediate to granitic plutons intruded the innermost part of Sesia-Lanzo Zone (SLZ) in western Alps. SLZ represents an early-Alpine continental high-pressure (HP) metamorphic complex forms subducted Adria margin along Periadriatic lineament, internal boundary axial Alpine belt. Intrusions postdate ductile deformation country rocks, but predate most late-orogenic brittle deformation. These cut across regional foliations that are dominated...

Lithospheric slices preserving pre-Alpine metamorphic imprints are widely described in the Alps. The Variscan parageneses recorded continental, oceanic, and mantle rocks suggest a heterogeneous evolution across Alpine domains. In this contribution, we collect quantitative ages of samples that document tectonometamorphic from 420 to 290 Ma. Based on age distribution imprint, three main stages can be identified for region: Devonian (early Variscan), late Devonian–late Carboniferous (middle...

The Sassa gabbro complex outcrops in the upper Valpelline and is part of Permian gabbros Collon – Matterhorn group, set Dent Blanche nappe Western Austroalpine tectonic system. This 1:2500-scale map was constructed through synergic use meso- microscopic analysis fabrics to identify relationships superposed foliations with growth equilibrium mineral assemblages. Throughout foliation trajectories, a mosaic rock volumes, which strain differently partitioned, highlighted on for all successive...

Abstract Microstructural analysis and P–T estimates of metamorphic pebbles in Permian conglomerates the Central Southern Alps, representing erosion product collapsing Variscan chain, are discriminating tools for determining sequences potential sources conglomerates. In selected case, basement units precisely outlined on basis quality P–T–d–t paths that allow reconstruction their evolutions (tectonometamorphic units); this facilitates individuation with much better confidence. The lower...

This work reconstructs the metamorphic evolution recorded in cobbles of Ponteranica Formation to be compared with evolutions basements central Southern Alps and clasts Aga Vedello Dosso dei Galli conglomerates. The is part lower volcano-sedimentary cycle Permian sequences western Orobic basin. These sequencescap Variscan basement which different tectono-metamorphic units were recognized contoured. We sampled all crystalline rock types preserved as such metapelites, meta-intrusives,...

Within the Zermatt-Saas Zone (ZSZ, northwestern Alps), Ti-chondrodite- and Ti-clinohumite-bearing assemblages in serpentinites indicate UHP conditions. Multiscale structural analysis (1:20 scale mapping) petrological investigation of at Créton (upper Valtournanche) evidenced a polyphasic deformation metamorphic history. In this locality regional scale, S2 is dominant foliation that developed under HP-UHP Pre-D2 mineral textural relicts are preserved despite pervasiveness S2. olivine +...

In this work a new form surface map at 1:5000 scale of the north-eastern margin Oligocene Traversella pluton, synthesized from field structural study assisted by optical petrography, is presented. Relative chronology superposed foliations and effects progress contact metamorphic reactions in aureole are shown on for each country rock-types Sesia-Lanzo Zone. The evolution was reconstructed across pluton separating pre- post-intrusive tectonic history defining outline. Contact assemblages...

The Lago della Vecchia-Valle d'Irogna rocks are part of the Eclogitic Micaschists Complex (EMC) Sesia-Lanzo Zone, western Austroalpine domain. 1:10,000 scale map includes metaintrusive, minor micaschist, banded gneiss, and metabasic boudins. multiscale structural analysis reveals successive magmatic tectono-metamorphic stages: during M0 metaintrusive protoliths emplaced; D1 took place under eclogite-facies conditions; D2 stage, a pervasive foliation developed retrograde blueschist-facies...

Abstract Italy, with 2% of the world's emissions and 13% European Union's emissions, has adopted a legally binding commitment to reduce its greenhouse gases by 6.5% below 1990 levels 2008 – 2012. This target will be reached implementing both domestic policies (80%) using Kyoto mechanisms (20%). The success mitigation effort depend on coordination at national local level incentives rewards given central government for initiatives undertaken ones. paper addresses question: What climate change...

A new foliation trajectory map at 1:10000 scale, represented here with an interpretative structural map, is derived from original field analysis 1:5000 scale in the southern Sesia-Lanzo Zone (SLZ). It shows relative chronology of overprinting foliations, characterised by mineral assemblages that mark superposed fabrics each rock type. This and associated cross-sections, which synthesise 3D outline tectonic contact between Eclogitic Micaschists Complex (EMC), Rocca Canavese Thrust Sheets...