Tectonostratigraphy of the northern Monviso Meta-ophiolite Complex (Western Alps)

• DOI: 10.3301/ijg.2014.13
• Publication Date: 2014-11-03T03:47:15Z
• Authors: Gianni Balestro; Bruno Lombardo; Gloria Vaggelli; Alessandro Borghi; Andrea Festa; Marco Gattiglio
• Keywords: HP meta-ophiolites; Monviso; Western Alps; tectonic units; Monviso; hp meta-ophiolite; tectonic units; Western Alps; 01 natural sciences; 0105 earth and related environmental sciences

The Monviso Meta-Ophiolite Complex is a remnant of the Piedmont-Ligurian oceanic lithosphere stacked in Western Alps, andconsisting dismembered HP meta-ophiolite sequences. In thiswork, focused on northern sector Complex, we differen -tiate six tectonic units which structural, petrographic and stratigraphiccharacteristics are described detail discussed thelight comparison with overall geology MonvisoMeta-Ophiolite Complex. structural evolution has been referredto i) an early syn-eclogitic deformation phase (D1), ii) main deformationphase (D2) occurred blueschist- to greenschist-faciestransition characterized by development regional foliation(S2) that parallel contacts axialplane map-scale W-verging folds, iii) late-metamorphicdeformation (D3) westward extensionaltectonic. characterizedby poor preservation paragenesis widespreadoverprint greenschist-facies metamorphism,but occurrence garnet-, omphacite-, talc- lawsoniteassemblagein Fe-Ti metagabbro indicates P-T eclogitic conditions(2.5-2.7 GPa for 550-570 �C) very similar those calculated thesouthern stratigraphic characteristics ofthe sequences point out that, differently from where basalt-poor basalt-richoceanic have distinguished, different types metasedimentsmay be key restore tectonostratigraphy, markedby gabbro mantle peridotite exposition puzzle-like oceanfloor basalt effusion sedimentation processestook place.