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The Jurassic ophiolites in the Northern Apennines and the Western Alps represent fossil mid-ocean ridge (MOR) oceanic lithosphere that formed in the Mesozoic Ligurian-Piedmont Ocean Basin (LPOB). Their sedimentary covers include chaotic rock units containing ophiolite-derived material. The processes of formation and the lithostratigraphic position of these chaotic units in the Western Alps remain a matter of debate, unlike their counterparts in the Northern Apennines. This is because of pervasive tectonic deformation and high-pressure metamorphism that affected their internal structure during collisional tectonics. A comparative analysis of these chaotic units in both mountain belts reveals the nature of processes involved in their formation. Chaotic deposits of gravitational origin occur both below and above the extrusive sequences in the ophiolites. They represent synextensional, hyperconcentrated deposits associated with the seafloor-spreading evolution of the LPOB lithosphere during Middle and Late Jurassic times. Mass transport deposits (MTDs) occur as intercalations within turbiditic sequences above the ophiolites. They represent syncontractional submarine slides that occurred on frontal accretionary prism slopes during the Late Cretaceous-Paleocene closure of the LPOB. The results of our comparative analysis imply that (1) the structure-stratigraphy of the chaotic deposits and MTDs of the Northern Apennines can be used as a proxy to better identify their metamorphosed and highly deformed counterparts in the Western Alps, (2) sedi-mentological processes associated with slow-spreading MOR tectonics and accretionary prism development in convergent-margin tectonics contributed to the sediment budgets of the cover sequences, and (3) magmatic, tectonic, and sedimen-tological processes that occurred during the formation of the Jurassic oceanic lithosphere and its sedimentary cover in the LPOB were remarkably uniform and synchronous.

Il Ghiacciaio Superiore di Coolidge, localizzato in alta Valle Po nel territorio comunale di Crissolo (CN), è l'ultimo sopravvissuto di un gruppo di apparati glaciali originariamente ospitati sul versante nord-orientale del Monviso. L'area, dominata dalla maestosa piramide del "Re di Pietra", oltre a comprendere la riserva naturale speciale del Pian del Re è a sua volta parte integrante del Sito di Interesse Comunitario (SIC) denominato "Gruppo del Monviso e Bosco dell'Allevè" (Codice IT1160058) nonché parte del Parco Naturale del Fiume Po. Nel 2013 il Massiccio del Monviso è stato formalmente riconosciuto come nuova Riserva della Biosfera nazionale e transfrontaliera nell'ambito del programma UNESCO Man and Biosphere. La fitta rete di sentieri e punti di appoggio, che consente un'agevole esplorazione a 360° del massiccio, rende inoltre questo settore delle Alpi Cozie uno dei luoghi più frequentati della catena alpina occidentale. L'itinerario descritto si sviluppa a partire dalle sorgenti del F. Po, situate al Pian del Re (2020 m), per giungere fino al Rifugio Quintino Sella (2640 m), localizzato alla base dell'imponente parete NE del Monviso. Il percorso si snoda attraverso un paesaggio suggestivo, profondamente segnato dal modellamento delle successioni meta-ofiolitiche da parte dei ghiacciai pleistocenici e, nell'area più prossima alla piramide del Monviso, dalla riavanzata delle fronti glaciali che ha contraddistinto la Piccola Età Glaciale. Le evidenze lasciate dal crollo di buona parte del Ghiacciaio pensile di Coolidge, avvenuto nell'estate del 1989, consentono inoltre di effettuare interessanti osservazioni sugli effetti indotti dal ritiro (generalmente graduale, talvolta parossistico) delle masse glaciali.

In order to promote geosite conservation in the project entitled 'PROactive management of GEOlogical heritage in the PIEMONTE Region', we propose a comprehensive study involving the Monviso Massif (MM) geothematic area, one of the most outstanding symbols of the Alps and particularly of the Cottian Alps. Specifically, at the MM, the inventory of a number of different geosites whose conservation and development require different geologic and some additional non-geological expertise is considered: (1) some of the best preserved ophiolites in the Alps and the associated Cu-Fe mineralizations; (2) the lithostructural units in the Germanasca Valley; (3) the first primary source of jade in the Alps at the MM and its importance in terms of Neolithic to Bronze Age-polished stone implements; (4) the world-famous minerals such as coesite and giant pyrope, as well as type localities for new minerals (including carlosturanite); (5) the area, now buried under a debris flow, where Hannibal is thought to have regrouped his army while crossing the Alps; and (6) the biodiversity of lichens, microfungi and cyanobacteria colonizing the ophiolites, which can give additional value for the environmental assessment and evaluation of the MM outcrops. Following geodiversity identification, further stages will be devoted to develop appropriate plans for geodiversity conservation in this area.

Collection and sharing of geoheritage information are nowadays enhanced by using digital tools and IT (Information Technology) applications that allow homogeneous storing of data, building of sharable databases, and transfer of knowledge between experts and communities. In the frame of the PROGEO-Piemonte project (PROactive management of GEOlogical heritage in the PIEMONTE region), the geological and geomorphological trail in the Monviso Massif (Western Alps) is an example of how IT-applications may support management of geoheritage information. The trail particularly allows walking across the meta-ophiolite succession of an ancient ocean and on glacial landforms. Its realization was supported by different tools that allow (i) capturing of data via GPS handheld mobile device, (ii) managing of field data by means of GIS (Geographic Information Systems) applications, and (iii) virtual visualization of data by means of GIS-based 3D viewer. The different (virtual) views of the geology along the trail can be implemented by adding photos and bookmarks and easily shared through web mapping tools that ensure wide accessibility of geoheritage information.

The Monviso Ophiolite (MO) in the Italian Western Alps is one of the best known relics of oceanic crust in the orogen. Moreover, it is one of the strategic areas chosen to represent the geodiversity of Piemonte Region (Rolfo et al. 2014). The MO gives the chance to see and appreciate different portions of the ancient ocean along a relatively short mountain trail; from the Po river springs at Pian del Re, a path from 2000 m up to about 2350 m a.s.l. shows all different ophiolitic lithologies - modified after the Alpine evolution - within few kilometers.

Iso-Kinematic maps have been derived from spatial statistics (Hot Spot and geostatistical analysis) of Permanent Scatterers Interferometric Synthetic Aperture Radar (PS-InSAR) data, and compared with geological, geomorphological, seismological and GPS data in order to analyse the current tectonics and the crustal mobility, at the boundary between the Cottian Alps and the Western Po Plain. This area corresponds to the subsurface junction between the Western Alpine chain and the Northern Apennines. PS data show that the Western Alps are currently uplifting with respect to the adjoining Western Po Plain, as confirmed by the GPS data. The Iso-Kinematic Boundary between these two sectors partly coincides with a regional N–S fault system developed along the inner seismogenic border of the Cottian Alps. Focal mechanisms indicate transpressive movements along this Iso-Kinematic Boundary, which separates two domains characterized by different fault geometry and kinematics, namely: (a) the Cottian Alps, where N–S transtensive/normal faults have developed, and (b) the subsurface Western Po Plain, where NW–SE transpressive/reverse faults are dominant. This articulated tectonic setting results from the complex strain partitioning of the oblique convergence between the European and Adria plates, which is still ongoing, as indicated by seismotectonic and geodetic data.

This work describes a conceptual and technical approach used to obtain a satisfactory description, representation and geometrical simulation of the fracture network of a poly-deformed blocky rock mass, characterized by tectonically coupled metamorphic and sedimentary rock units in the Ligurian Alps (Italy). The geological knowledge of the study area (about one hundred square kilometres) was obtained from recent researches that allowed relatively continuous mapping of the main macroscopic structural features and a description of their associated fault and fracture patterns to be made. An analysis of aerial photo and satellite lineaments was performed to complete the reference framework of the collected data and allowed an analysis of the fractal properties of the fracture pattern to be made. A statistical evaluation of the natural jointing parameters was carried out on the basis of the geological knowledge using different steps and techniques for the analysis and geometrical modelling for the joint set separation and their characterization, the jointing intensity measures and the joint size. This characterization enables a definition to be made of the suitable parameters of the fracture sets, the construction of a 3D geometrical model and its validation through a comparison with the original geological constraints.

Le Tecnologie dell'Informazione (IT), permettendo l'applicazione di nuove metodologie di rappresentazione del dato e favorendo la condivisione delle informazioni, rappresentano un'opportunità per superare alcuni limiti nell'utilizzo e nella diffusione delle carte geologiche. Per trarre effettivi vantaggi dall'utilizzo di tecnologie quali i Sistemi Informativi Geografici e i servizi di web-mapping, è però necessario che le informazioni contenute nelle carte geologiche siano specificatamente strutturate e standardizzate. In questo ambito, i protocolli WMS (Web Map Service) e gli standard previsti dalla direttiva INSPIRE (Infrastructure for Spatial Information in Europe) rappresentano importanti strumenti per la creazione e il mantenimento di geoportali contenenti informazioni geologiche interoperabili. Il geoportale dell'Unità di Torino dell'Istituto di Geoscienze e Georisorse del CNR (CNR-IGGTO) è un esempio di condivisione delle banche dati delle carte geologiche attraverso l'utilizzo di servizi standard di web-mapping e la compilazione di metadati con contenuti geologici.

The 1:5000 scale Geological Map of the Fontane talc mineralization (FTM) aims to give new information about the origin and geological structure of an important talc mineralization occurring in the axial sector of the Italian Western Alps. The FTM is hosted within a pre-Carboniferous polymetamorphic complex which was deformed and metamorphosed during both Variscan and Alpine orogenesis, and is part of the Dora-Maira continental crust. Field mapping and underground investigations highlight that the talc bodies (i) never crop out but occur at depth along a well-defined lithostratigraphic association between micaschist, marble and gneiss and (ii) were deformed during different Alpine-related deformation phases (i.e. D1, D2 and D3 syn-metamorphic phases and post-metamorphic extensional faulting). The here defined lithostratigraphic and structural characterization of talc bodies, is an input for further research into the geodynamic context of where talc forms and for new mineral exploration outside the mapped area.

Chaotic rock units with block-in-matrix structure, commonly known as mélanges and broken formations, are one of the hallmarks of the Alpine orogenic system and of many exhumed convergent plate margins throughout the world. They commonly form in different tectonic settings and structural levels during the evolution of convergent plate margins, reflecting a close relationship between the active processes (tectonic, sedimentary and diapiric), and the physical and mechanical conditions experienced by rocks. Hence, systematic and process-oriented, inter-disciplinary studies of these units may provide much-needed information about the evolution of the Alpine orogenic system and convergent plate margins in general. The relationships between the final block-in-matrix structure and the processes of their formation commonly are, however, obscure and controversial, because of the complex and seemingly chaotic nature. The overlap of shearing, tectonic mixing, and metamorphic recrystallization lead to the reworking and change of the initial block-in-matrix structures formed by different processes (e.g., sedimentary or diapiric), and to the formation of polygenetic mélange. In this framework, block-in-matrix units formed by sedimentary processes may result very difficult-to non-distinguishable when placed in settings such as, for example, accretionary wedges or in a subduction channels or after a complete cycle from subduction to collision, exhumation and intra-continental deformation. We present here different examples of block-in-matrix bodies from the Alpine orogenic system, showing that at shallower structural levels, mélange-forming processes commonly operate in complex and mutual interactions, hence in partial superposition and rarely in isolation. In the geological record of mélanges we commonly observe as the best preserved evidence the artifacts of the last and/or more pervasive process. In most cases, the latter is consistent with tectonics, although sedimentary and/or diapiric-derived structures still characterize notably examples. We show here a comparative analysis of on-land exhumed examples of mélanges and tectonic environments where mélange-forming processes are currently operating. Main types of deformational mode leading to mélange formation include extensional, strike-slip, convergent margin/collisional tectonics, and intra-continental deformation. We discuss: (1) possible relationships between various mélange types and their tectonic setting of formation; (2) contribution of mass-transport versus contractional tectonic deformation processes at the onset of mélange formation (3) nature of the “continuum” and transition from broken formations to true tectonic mélanges.