transported and deposited by fast-flowing rivers (Ponte Raut succession), that episodically flooded their alluvial plains (Bourcet succession) or invaded ephemeral lakes (Pons succession). This is quite typical of all "intramontane" basins developed on top of the collapsing Variscan belt during the Late Carboniferous (e.g. Ballèvre et al., 2018).

## 7.3 Permian history

Accepting the Carboniferous age of the Pinerolo meta-sediments and considering the Permian age of the orthogneisses found in the Pinerolo Unit (Bussy and Cadoppi, 1996), we should expect to find evidence of primary intrusive relationships of the granitic and dioritic magmatic bodies into the Carboniferous sediments. From sample to outcrop scale and map scale, the contact between the orthoderivates and the meta-sediments is parallelized to the main Alpine foliation. Decisive field evidence that the magmatic bodies were intruded into the sediments of the Pinerolo Unit has not been found yet. However, one can note that Novarese (1895b) reported the occurrence of cm-sized aggregates consisting of white mica ± chloritoid ± chlorite in graphite-rich schists close to the Freidour Orthogneiss (lower Sangone Valley) and dioritic bodies (lower and middle Chisone Valley). Novarese (1895b) interpreted them as pseudomorphs after andalusite derived from the contact metamorphism associated with emplacement of the magmatic bodies.

Permian acidic and intermediate magmatism (both intrusive and extrusive) is widespread in the Dora-Maira Massif and, in general, in the Briançonnais Domain, whereas it is essentially absent in the External Massifs, where a Carboniferous magmatism is recorded instead (Ballèvre et al., 2018, 2020, and references therein). During the Permian, high temperature metamorphism and partial melting was occurring in the lower crust, whereas melt was emplaced in the upper crust, with volcanism and opening of fault-bounded basins at the surface. The Permian volcanic and volcaniclastic rocks in the Serre Unit represents such upper crustal products. This dynamic event records the collapse of the Variscan belt, possibly concurrent with the activation of transcurrent faults such as the East Variscan Shear Zone (Ballèvre et al., 2018; Elter et al., 2020; Simonetti et al., 2020; Fréville et al., 2022, Vanardois et al., 2022; Bühler et al., 2023). The new data provided in this study are consistent with the palaeogeography as depicted in Ballèvre et al. (2018).

## 7.4 Mesozoic history

Given the intensity of the Alpine deformation, the Mesozoic history can only be rather poorly documented. In

the Serre Unit, dolostones, marbles and calcschists, are generally found on top of the Permian magmatic and sedimentary rocks. This carbonate-bearing succession is characteristic of the Mesozoic cover (Fig. 10). Although we have not been able to find fossils in the studied area, some have been found in similar lithologies further south, in the Maira Valley (Franchi, 1911; Michard, 1967), and north, in the Susa Valley (Franchi 1911; Marthaler et al., 1986). By comparison with the “classical” Mesozoic successions in the External Briançonnais (e.g. Ellenberger, 1958) or with the “Pre-Piemonte-type” successions in the Internal Briançonnais (including the Val Maira-Sampeyre Unit and Val Grana Unit along the south-eastern margin of the Dora-Maira Massif; Balestro et al., 2022; Michard et al., 2022; Pantet et al., 2022; Dana et al., 2023), dolostones are typically considered Middle to Upper Triassic in age and limestones and calcschists can be considered Jurassic and Cretaceous in age, respectively (Fig. 10).

This sedimentation is the result of Triassic crustal extension, subsequent Jurassic rifting of Pangea with development of the Briançonnais passive margin, and final oceanic spreading starting from the Mid- to Late Jurassic (e.g. Lemoine and Trümpy, 1987; Cordey and Bailly, 2007). It has been proposed that the units of the Dora-Maira Massif constituted different crustal fragments already during the Mesozoic as part of the extended Briançonnais palaeomargin (Ballèvre et al., 2020; Bonnet et al., 2022). In such a hypothesis, the different units were separated by normal faults or, in case they represented extensional allochthons, by exhumed mantle or oceanic crust. Tectonic slices of serpentinites and meta-basites are, in fact, found along the boundary between two units (the Rocca-Solei Dronero Units) in the southern part of the massif, where they constitute the Valmala-Piasco Shear Zone. This hypothesis may also be valid in the northern Dora-Maira Massif, being supported by the occurrence of serpentinites at the contact between the Muret and the Serre Units.

## 7.5 Alpine history

The Alpine tectonic history of the northern Dora-Maira Massif consists of several superposed episodes (Fig. 18). The oldest recognizable stages are associated with the burial of the thinned continental margin in a subduction zone. Witnesses of this stage are, paradoxically, the lack of Mesozoic cover on top of the Pinerolo Unit, because it should have been detached already in the earliest stages of burial. More direct evidence of this burial is recorded by the early growth stages of garnet in the Chasteiran (Manzotti et al., 2022) and Muret Units (Nosenzo et al., 2023). The development of HP to UHP assemblages is associated, with a few exceptions, to a pervasive ductile deformation (D₁).
Stacking of the different units from the Dora-Maira Massif has taken place during exhumation, associated to the main, regional, ductile deformation (D₂), in the albite stability field. The main ductile boundary in the nappe stack is the one separating in the footwall the Pinerolo Unit and in the hangingwall the Muret Unit. The *UHP* Chasteiran Unit is located along this boundary (Fig. 3), in a similar position than the *UHP* Brossasco-Isasca Unit in the southern Dora-Maira Massif (e.g. Henry et al., 1993). In the studied area, the mylonitic deformation of the Granero Orthogneiss is the clearest expression of the tectonic boundary between the Pinerolo and Muret Units, in this case characterized by a top-to-the-West displacement of the hangingwall with respect to the footwall. Details of these two deformation stages (D₁ and D₂) need due consideration of the *P–T–t* history of the units now in contact, but widely separated in the subduction zone, a topic that requires further geochronological and petrological data, beyond the scope of this paper.

Late reworking of some tectonic boundaries at the ductile to brittle transition has taken place, especially along the western margin of the Dora-Maira Massif. Specifically, the contact between the Muret and Serre Units is marked by a thin (a few metres thick) but marked zone of deformation, with CS structures and asymmetric folds overprinting the D₂ deformation (Figs. 15, 16, 17). These top-to-the-NW structures may be related to the late deformation along the Vallanta-Susa Shear Zone, a D₃ structure cutting across and reworking most of the nappe stack along the western margin of the Dora-Maira Massif (Ballèvre et al., 1990; Ghignone et al., 2020).

Finally, late brittle normal faults (i.e. the Trossieri Fault in the study area), cut across the nappe stack as well as the Vallanta-Susa Shear Zone. These late faults are identified inside the Dora-Maira Massif and may be linked to the present seismotectonic frame (e.g. Perrone et al., 2009).

## 8 Conclusions and perspectives

The main conclusions of our field and geochronological investigations in the northern Dora-Maira Massif are as follows (Fig. 18).

1. The lowermost unit, i.e. the Pinerolo Unit, consists of Late Carboniferous sediments deposited in a variety of environments, from fluvial to lacustrine. The sediments have been intruded by granitic and dioritic plutonic bodies. Their putative sedimentary cover has been detached from the downgoing slab at the onset of the Alpine orogenic history.

2. A major ductile shear zone, assumed to be a westward thrust, emplaces the Chasteiran and Muret Units on top of the Pinerolo Unit. The polycyclic basement of the Muret Unit consists of late Neoproterozoic to early Palaeozoic sediments intruded by late Ordovician to early Silurian granitoid bodies. At map scale, we propose that the basal contact of the Muret Unit is best defined by a remarkable reference layer, namely the Granero Orthogneiss.

3. On top of the nappe stack, the Serre Unit, consisting of Permian plutonic, volcanic and volcano-clastic rocks, and a thin Mesozoic cover, is separated from its footwall by a narrow, ductile to brittle, shear zone (La Fracho Shear Zone).

4. The nappe stack is lately affected by normal faulting, indicating a NNW-SSE extensional episode.

Overall, the tectonic stack of the Dora-Maira Massif is consistent from north to south. The metamorphic architecture is analogous in the northern and southern part of the massif, with a *UHP* unit sandwiched between two lower *P* units, the Pinerolo Unit below and a basement unit above. Further investigations in the Pinerolo and Serre Units, will be necessary to evaluate differences of *P–T* conditions, and their potential link with the tectonic history.

## Supplementary Information

The online version contains supplementary material available at https://doi.org/10.1186/s00015-024-00459-2.

**Additional file 1: Appendix S1.** Operating conditions of LA-ICP-MS equipment for zircon U–Pb analysis. Working conditions for session1 refer to the samples OG34, OG36 and OG9, whereas those for session2 refer to samples OG49, PG3 and PG41, as the samples were analysed on different days. **Appendix S2.** Operating conditions of LA-ICP-MS equipment for zircon trace element analysis. Working conditions for session1 refer to the samples OG34, OG36 and OG9, whereas those for session2 refer to sample OG49, as the samples were analysed on different days. **Figure S1.** Whole-rock geochemistry of the studied orthogneiss (sample OG34, OG36 and OG49, Granero Orthogneiss; sample OG7 and OG9, Clapier Orthogneiss). a R1–R2 classification diagram for plutonic and volcanic rocks (De La Roche et al., 1980). The Muret Orthogneiss (sample OG27, Nosenzo et al., 2022), the Sangone Orthogneiss, the Freidour Orthogneiss, the Cavour Orthogneiss and the Malanaggio Meta-diorite (San., Fre., Cav. and Mal., respectively; Bussy & Cadoppi, 1990) are also plotted for comparison. b Total alkali vs. silica (TAS) classification diagram for volcanic rocks (Le Maitre et al., 2002). **Figure S2.** Concordia diagram for the Granero Orthogneiss. Data from samples OG34, OG36, and OG49 are plotted together. Empty dashed ellipses represent dates excluded from the concordia age calculation, as they are affected by Pb loss or mixing with metamorphic rims. **Table S1.** Bulk-rock compositions of orthogneisses in the northern Dora-Maira Massif.

**Additional file 2: Table S2.** Zircon U–Pb and trace element dataset.

## Acknowledgements

An excursion with Stefan Schmid helped us clarifying some of the major questions in our field area. We have been also pleased to show the Bourcet section to the Torino team (Rodolfo Carosi, Chiara Montomoli and Salvatore Iaccarino and Davide Dana) who is now in charge of mapping the Foglio 172—Pinerolo. William Westin, a Swedish MSc student, accompanied during one field season. We also warmly thank Andrea Pane and Manuela Juvenal for their introduction
Stacking of the different units from the Dora-Maira Massif has taken place during exhumation, associated to the main, regional, ductile deformation (D₂), in the albite stability field. The main ductile boundary in the nappe stack is the one separating in the footwall the Pinerolo Unit and in the hangingwall the Muret Unit. The *UHP* Chasteiran Unit is located along this boundary (Fig. 3), in a similar position than the *UHP* Brossasco-Isasca Unit in the southern Dora-Maira Massif (e.g. Henry et al., 1993). In the studied area, the mylonitic deformation of the Granero Orthogneiss is the clearest expression of the tectonic boundary between the Pinerolo and Muret Units, in this case characterized by a top-to-the-West displacement of the hangingwall with respect to the footwall. Details of these two deformation stages (D₁ and D₂) need due consideration of the *P–T–t* history of the units now in contact, but widely separated in the subduction zone, a topic that requires further geochronological and petrological data, beyond the scope of this paper.

Late reworking of some tectonic boundaries at the ductile to brittle transition has taken place, especially along the western margin of the Dora-Maira Massif. Specifically, the contact between the Muret and Serre Units is marked by a thin (a few metres thick) but marked zone of deformation, with CS structures and asymmetric folds overprinting the D₂ deformation (Figs. 15, 16, 17). These top-to-the-NW structures may be related to the late deformation along the Vallanta-Susa Shear Zone, a D₃ structure cutting across and reworking most of the nappe stack along the western margin of the Dora-Maira Massif (Ballèvre et al., 1990; Ghignone et al., 2020).

Finally, late brittle normal faults (i.e. the Trossieri Fault in the study area), cut across the nappe stack as well as the Vallanta-Susa Shear Zone. These late faults are identified inside the Dora-Maira Massif and may be linked to the present seismotectonic frame (e.g. Perrone et al., 2009).

## 8 Conclusions and perspectives

The main conclusions of our field and geochronological investigations in the northern Dora-Maira Massif are as follows (Fig. 18).

1. The lowermost unit, i.e. the Pinerolo Unit, consists of Late Carboniferous sediments deposited in a variety of environments, from fluvial to lacustrine. The sediments have been intruded by granitic and dioritic plutonic bodies. Their putative sedimentary cover has been detached from the downgoing slab at the onset of the Alpine orogenic history.

2. A major ductile shear zone, assumed to be a westward thrust, emplaces the Chasteiran and Muret Units on top of the Pinerolo Unit. The polycyclic basement of the Muret Unit consists of late Neoproterozoic to early Palaeozoic sediments intruded by late Ordovician to early Silurian granitoid bodies. At map scale, we propose that the basal contact of the Muret Unit is best defined by a remarkable reference layer, namely the Granero Orthogneiss.

3. On top of the nappe stack, the Serre Unit, consisting of Permian plutonic, volcanic and volcano-clastic rocks, and a thin Mesozoic cover, is separated from its footwall by a narrow, ductile to brittle, shear zone (La Fracho Shear Zone).

4. The nappe stack is lately affected by normal faulting, indicating a NNW-SSE extensional episode.

Overall, the tectonic stack of the Dora-Maira Massif is consistent from north to south. The metamorphic architecture is analogous in the northern and southern part of the massif, with a *UHP* unit sandwiched between two lower *P* units, the Pinerolo Unit below and a basement unit above. Further investigations in the Pinerolo and Serre Units, will be necessary to evaluate differences of *P–T* conditions, and their potential link with the tectonic history.

## Supplementary Information

The online version contains supplementary material available at https://doi.org/10.1186/s00015-024-00459-2.

**Additional file 1: Appendix S1.** Operating conditions of LA-ICP-MS equipment for zircon U–Pb analysis. Working conditions for session1 refer to the samples OG34, OG36 and OG9, whereas those for session2 refer to samples OG49, PG3 and PG41, as the samples were analysed on different days. **Appendix S2.** Operating conditions of LA-ICP-MS equipment for zircon trace element analysis. Working conditions for session1 refer to the samples OG34, OG36 and OG9, whereas those for session2 refer to sample OG49, as the samples were analysed on different days. **Figure S1.** Whole-rock geochemistry of the studied orthogneiss (sample OG34, OG36 and OG49, Granero Orthogneiss; sample OG7 and OG9, Clapier Orthogneiss). a R1–R2 classification diagram for plutonic and volcanic rocks (De La Roche et al., 1980). The Muret Orthogneiss (sample OG27, Nosenzo et al., 2022), the Sangone Orthogneiss, the Freidour Orthogneiss, the Cavour Orthogneiss and the Malanaggio Meta-diorite (San., Fre., Cav. and Mal., respectively; Bussy & Cadoppi, 1990) are also plotted for comparison. b Total alkali vs. silica (TAS) classification diagram for volcanic rocks (Le Maitre et al., 2002). **Figure S2.** Concordia diagram for the Granero Orthogneiss. Data from samples OG34, OG36, and OG49 are plotted together. Empty dashed ellipses represent dates excluded from the concordia age calculation, as they are affected by Pb loss or mixing with metamorphic rims. **Table S1.** Bulk-rock compositions of orthogneisses in the northern Dora-Maira Massif.

**Additional file 2: Table S2.** Zircon U–Pb and trace element dataset.

## Acknowledgements

An excursion with Stefan Schmid helped us clarifying some of the major questions in our field area. We have been also pleased to show the Bourcet section to the Torino team (Rodolfo Carosi, Chiara Montomoli and Salvatore Iaccarino and Davide Dana) who is now in charge of mapping the Foglio 172—Pinerolo. William Westin, a Swedish MSc student, accompanied during one field season. We also warmly thank Andrea Pane and Manuela Juvenal for their introduction
to the past mining activities in the studied area. The two reviewers (Giancarlo Molli and Francesca Piccoli) are thanked for their useful remarks on the manuscript. The editorial work of Adrian Pfiffner has been greatly appreciated.

**Author contributions**

FN: Investigation (fieldwork, geochronological data acquisition), figures preparation, writing—original draft. PM: conceptualization, supervision, funding acquisition, investigation (fieldwork), figures preparation, writing—original draft. MK: Investigation (geochronological data acquisition) writing—review and editing. MB: Investigation (fieldwork), figures preparation, writing—original draft. MP: geochronological data curation and processing, writing—review and editing. All authors contributed to the discussion and read and approved the final version of the manuscript.

**Funding**

Open access funding provided by Stockholm University. This work was financially supported by the Swiss National Science Foundation (Advanced Post-Doc Mobility: Project P300P2_147762, Ambizione: Project PZ00P2_161202), the Carl Tryggers Stiftelse (Fund CTS21:1301) and a Starting Grant from Stockholm University to Paola Manzotti. Fieldwork conducted by Francesco Nosenzo was partially supported by the Jubileumsdonationen K & A Wallenbergs Stiftelse 2020. Field work conducted by Michel Ballèvre was supported by his pension.

**Availability of data and materials**

The online version contains supplementary material available at XXXX (Additional files).

**Declarations**

**Ethics approval and consent to participate**

Not applicable.

**Consent for publication**

Not applicable.

**Competing interests**

Paola Manzotti is Associate Editor of this journal. The authors have no other competing interests to declare that are relevant to the content of this article.

Received: 14 February 2024 Accepted: 11 March 2024

Published online: 22 April 2024

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Álvaro, J. J., Sánchez-García, T., Puddu, C., Casas, J. M., Díez-Montes, A., Liesa, M., & Oggiano, G. (2020). Comparative geochemical study on Furongian—earliest Ordovician (Toledanian) and Ordovician (Sardic) felsic magmatic events in south-western Europe: Underplating of hot mafic magmas linked to the opening of the Rheic Ocean. *Solid Earth, 11*, 2377–2409.

Avigad, D. (1992). Exhumation of coesite-bearing rocks in the Dora Maira massif (Western Alps, Italy). *Geology, 20*, 747–950.

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Balestro, G., Festa, A., Cadoppi, P., Groppo, C., & Roà, M. (2022). Pre-orogenic tectonostratigraphic evolution of the European distal margin-Alpine Tethys transition zone in high-pressure units of the southwestern Alps. *Geosciences, 12*, 385.

Balestro, G., Fioraso, G., & Lombardo, B. (2011). Geological map of the upper Pellice valley (Italian Western Alps). *Journal of Maps, 7*, 634–654.

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Ballèvre, M., Fourcade, S., Capdevila, R., Peucat, J.-J., Cocherie, A., & Fanning, C. M. (2012). Geochronology and geochemistry of Ordovician felsic volcanism in the Southern Armorican Massif (Variscan belt, France): Implications for the breakup of Gondwana. *Gondwana Research, 21*, 1019–1036.

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to the past mining activities in the studied area. The two reviewers (Giancarlo Molli and Francesca Piccoli) are thanked for their useful remarks on the manuscript. The editorial work of Adrian Pfiffner has been greatly appreciated.

**Author contributions**

FN: Investigation (fieldwork, geochronological data acquisition), figures preparation, writing—original draft. PM: conceptualization, supervision, funding acquisition, investigation (fieldwork), figures preparation, writing—original draft. MK: Investigation (geochronological data acquisition) writing—review and editing. MB: Investigation (fieldwork), figures preparation, writing—original draft. MP: geochronological data curation and processing, writing—review and editing. All authors contributed to the discussion and read and approved the final version of the manuscript.

**Funding**

Open access funding provided by Stockholm University. This work was financially supported by the Swiss National Science Foundation (Advanced Post-Doc Mobility: Project P300P2_147762, Ambizione: Project PZ00P2_161202), the Carl Tryggers Stiftelse (Fund CTS21:1301) and a Starting Grant from Stockholm University to Paola Manzotti. Fieldwork conducted by Francesco Nosenzo was partially supported by the Jubileumsdonationen K & A Wallenberg's Stiftelse 2020. Field work conducted by Michel Ballèvre was supported by his pension.

**Availability of data and materials**

The online version contains supplementary material available at XXXX (Additional files).

**Declarations**

**Ethics approval and consent to participate**

Not applicable.

**Consent for publication**

Not applicable.

**Competing interests**

Paola Manzotti is Associate Editor of this journal. The authors have no other competing interests to declare that are relevant to the content of this article.

Received: 14 February 2024 Accepted: 11 March 2024

Published online: 22 April 2024

**References**

Agard, P. (2023). Oceanic subduction in the Alps: lessons from the rock record. In: Rosenberg, C.L., Bellahsen, N., Geodynamics of the Alps, Pre-colli- sional Processes, 2, pp. 205–244.

Álvaro, J. J., Sánchez-García, T., Puddu, C., Casas, J. M., Díez-Montes, A., Liesa, M., & Oggiano, G. (2020). Comparative geochemical study on Furongian— earliest Ordovician (Toledanian) and Ordovician (Sardic) felsic magmatic events in south-western Europe: Underplating of hot mafic magmas linked to the opening of the Rheic Ocean. *Solid Earth, 11*, 2377–2409.

Avigad, D. (1992). Exhumation of coesite-bearing rocks in the Dora Maira massif (Western Alps, Italy). *Geology, 20*, 747–950.

Avigad, D., Chopin, C., & Le Bayon, R. (2003). Thrusting and extension in the southern Dora-Maira ultra-high-pressure massif (Western Alps): View from below the coesite-bearing unit. *The Journal of Geology, 111*, 57–70.

Balestro, G., Festa, A., Cadoppi, P., Groppo, C., & Roà, M. (2022). Pre-orogenic tectonostratigraphic evolution of the European distal margin-Alpine Tethys transition zone in high-pressure units of the southwestern Alps. *Geosciences, 12*, 385.

Balestro, G., Fioraso, G., & Lombardo, B. (2011). Geological map of the upper Pellice valley (Italian Western Alps). *Journal of Maps, 7*, 634–654.

Ballèvre, M., Camonin, A., Manzotti, P., & Poujol, M. (2020). A step towards unraveling the paleogeographic attribution of pre-Mesozoic basement complexes in the Western Alps based on U-Pb geochronology of Permian magmatism. *Swiss Journal of Geosciences, 133*, 12.

Ballèvre, M., Fourcade, S., Capdevila, R., Peucat, J.-J., Cocherie, A., & Fanning, C. M. (2012). Geochronology and geochemistry of Ordovician felsic volcanism in the Southern Armorican Massif (Variscan belt, France): Implications for the breakup of Gondwana. *Gondwana Research, 21*, 1019–1036.

Ballèvre, M., Manzotti, P., & Dal Piaz, G. V. (2018). Pre-Alpine (Variscan) inheritance: A key for the location of the future Valaisan Basin (Western Alps). *Tectonics, 37*, 786–817.

Ballèvre, M., Lagabrielle, Y., & Merle, O. (1990). Tertiary ductile normal faulting as a consequence of lithospheric stacking in the western Alps. *Mémoires de la Société Géologique de France, 156*, 227–236.

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Corno, A., Mosca, P., Groppo, C., Borghi, A., & Gattiglio, M. (2022). More wide-spread than supposed: Preserved lawsonite in the blueschist-facies ophiolitic bodies from the Albergian Unit (Liguria-Piemonte Zone, Western Alps). *Ofioliti*, 47, 137–154.

Cruciani, G., Franceschelli, M., Musumeci, G., Spani, M. E., & Tiepolo, M. (2013). U-Pb zircon dating and nature of metavolcanics and metarkoses from the Monte Grigni Unit: New insights on Late Ordovician magmatism in the Variscan belt in Sardinia, Italy. *International Journal of Earth Sciences*, 102, 2077–2096.

Coleman, R. G., & Wang, X. (1995). *Ultrahigh pressure metamorphism* (p. 528). Cambridge University Press.

Dana, D., Iaccarino, S., Schmid, S. M., Petroccia, A., & Michard, A. (2023). Structural and metamorphic evolution of a subducted passive margin: Insights from the Briançonnais nappes of the Western Alps (Ubaye-Maira valleys, France-Italy). *Swiss Journal of Geosciences*, 116, 18.

De La Roche, H., Leterrier, J., Grandclaude, P., & Marchal, M. (1980). A classification of volcanic and plutonic rocks using R₁R₂-diagram and major element analyses—Its relationships with current nomenclature. *Chemical Geology*, 29, 183–210.

Dickinson, W. R., & Gehrels, G. E. (2009). Use of U-Pb ages of detrital zircons to infer maximum depositional ages of strata: A test against a Colorado Plateau Mesozoic database. *Earth and Planetary Science Letters*, 288, 115–125.

Ellenberger, F. (1958). Etude géologique du Pays de Vanoise (Savoie). Paris: Mémoires de la Carte Géologique de la France, Imprimerie Nationale. p. 561.

Elter, F. M., Gaggero, L., Mantovani, F., Pandeli, E., & Costamagna, L. C. (2020). The Atlas-East Variscan-Elbe shear system and its role in the formation of the pull-apart Late Palaeozoic basins. *International Journal of Earth Sciences*, 109, 739–760.

Epard, J.-L., & Steck, A. (2008). Structural development of the Tso Morari ultra-high pressure nappe of the Ladakh Himalaya. *Tectonophysics*, 451, 242–264.

Ewing, T. A., Rubatto, D., Lemke, K., & Hermann, J. (2023). Timescales and mechanisms of felsic lower continental crust formation: Insights from U-Pb geochronology of detrital zircon (Malenco Unit, eastern Central Alps). *Lithos*, 456–457, 107286.

Fielding, C. R. (2021). Late Palaeozoic cyclothems—A review of their stratigraphy and sedimentology. *Earth-Science Reviews*, 217, 103612.

Forno, M. G., Fubelli, G., Gattiglio, M., Taddia, G., & Ghignone, S. (2022). Object-based geomorphological mapping: Application on an Alpine deep-seated gravitational slope deformation contest (Germanasca Valley, Western Alps—Italy). *Applied Sciences*, 12, 778.

Forster, M. A., & Lister, G. S. (2005). Several distinct tectono-metamorphic slices in the Cycladic eclogite-blueschist belt, Greece. *Contribution to Mineralogy and Petrology*, 150, 523–545.

Franchi, S. (1911). Il Retico quale zona di transizione fra la Dolomia principale ed il Lias a "facies piemontese"-calcescisti con Belemniti e pietre verdi - nell'alta Valle di Susa. *Bollettino del Reale Comitato Geologico d'Italia*, XLI(3), 1–37.

Fréville, K., Trap, P., Vanardois, J., Melleton, J., Faure, M., Bruguier, O., Pojoul, M., & Lach, P. (2022). Carboniferous-Permian tectono-metamorphic evolution

of the Pelvoux Massif (External Crystalline Massif, Western Alps), with discussion on flow kinematics of the Eastern-Variscan Shear Zone. *BSGF Earth Science Bulletin*, 193, 13.

García-Arias, M., Díez-Montes, A., Villaseca, C., & Blanco-Quintero, I. F. (2018). The Cambro-Ordovician Ollo de Sapo magmatism in the Iberian Massif and its Variscan evolution: A review. *Earth-Science Reviews*, 176, 345–372.

Gasco, I., Gattiglio, M., & Borghi, A. (2011). Lithostratigraphic setting and P-T metamorphic evolution for the Dora-Maira Massif along the Piedmont Zone boundary (middle Susa Valley, NW Alps). *International Journal of Earth Sciences*, 100, 1065–1085.

Ghignone, S., Balestro, G., Gattiglio, M., & Borghi, A. (2020). Structural evolution along the Susa Shear Zone: The role of a first-order shear zone in the exhumation of meta-ophiolite units (Western Alps). *Swiss Journal of Geosciences*, 113, 17.

Ghignone, S., Borghi, A., Balestro, G., Castelli, D., Gattiglio, M., & Groppo, C. (2021). HP tectono-metamorphic evolution of the Internal Piedmont Zone in Susa Valley (Western Alps): New petrologic insight from garnet+chloritoid-bearing micaschists and Fe-Ti metagabbro. *Journal of Metamorphic Geology*, 39, 391–416.

Gilotti, J. A. (2013). The realm of ultrahigh-pressure metamorphism. *Elements*, 9, 255–260.

Gilotti, J. A., McClelland, W. C., Schorn, S., Compagnoni, R., & Coble, M. A. (2023). Provenance, protolith and metamorphic ages of jadeite-bearing orthogneiss and host paragneiss at Tavagnasco, the Sesia Zone, Lower Aosta Valley, Italy. *European Journal of Mineralogy*, 35, 645–658.

Glodny, J., & Ring, U. (2022). The Cycladic Blueschist Unit of the Hellenic subduction orogen: Protracted high-pressure metamorphism, decompression and reimbrication of a diachronous nappe stack. *Earth-Science Reviews*, 224, 103883.

Grasemann, B., Huet, B., Schneider, D. A., Rice, H. N., Lemonnier, N., & Tschegg, C. (2018). *Geological Society of America Bulletin*, 130, 238–262.

Groppo, C., Ferrando, S., Gilio, M., Botta, S., Nosenzo, F., Balestro, G., Festa, A., & Rolfo, F. (2019). What's in the sandwich? New P-T constraints for the (U) HP nappe stack of southern Dora-Maira Massif (Western Alps). *European Journal of Mineralogy*, 31, 665–683.

Handy, M. R., Schmid, S. M., Bousquet, R., Kissling, E., & Bernoulli, D. (2010). Reconciling plate-tectonic reconstructions of Alpine Tethys with the geological–geophysical record of spreading and subduction in the Alps. *Earth-Science Reviews*, 102, 121–158.

Henry, C., Michard, A., & Chopin, C. (1993). Geometry and structural evolution of ultra-high pressure and high pressure rocks from the Dora-Maira massif, western Alps, Italy. *Journal of Structural Geology*, 15, 965–981.

Horstwood, M. S. A., Košler, J., Gehrels, G., Jackson, S. E., Mc, L. N., Paton, C., Pearson, N. J., Sircombe, K., Sylvester, P., Vermeesch, P., Bowring, J. F., Condon, D. J., & Schoene, B. (2016). Community-derived standards for LA-ICP-MS U-(Th-) Pb geochronology—Uncertainty propagation, age interpretation and data reporting. *Geostandards and Geoanalytical Research*, 40, 311–332.

Hoskin, P.W.O., & Schaltegger, U (2003) The composition of zircon and igneous and metamorphic petrogenesis. In: Hanchar, J.M., & Hoskin, P.W.O. (eds) Zircon. Mineralogical Society of America, Washington, 53, 27–62.

Jackson, S. E., Pearson, N. J., Griffin, W. L., & Belousova, E. A. (2004). The application of laser ablation-inductively coupled plasma-mass spectrometry to in situ U-Pb zircon geochronology. *Chemical Geology*, 211, 47–69.

Jannin, P., & Magri, F. (2017). *Antiche miniere delle Alpi Cozie. Guida storico-escursinistica (volume 2)* (p. 350). Alzani Editore.

Le Bayon, B., & Ballèvre, M. (2006). Deformation history of a subducted continental crust (Gran Paradiso, Western Alps): Continuing crustal shortening during exhumation. *Journal of Structural Geology*, 28, 793–815.

Le Maitre, R. W. (2002). *Igneous rocks. A classification and glossary of terms*. Cambridge: Cambridge University Press.

Lemoine, M., & Trümpy, R. (1987). Pre-oceanic rifting in the Alps. *Tectonophysics*, 133, 305–320.

Liu, F. L., Gerdes, A., & Xue, H. M. (2009). Differential subduction and exhumation of crustal slices in the Sulu HP-UHP metamorphic terrane: Insights from mineral inclusions, trace elements, U-Pb and Lu-Hf isotope analyses of zircon in orthogneiss. *Journal of Metamorphic Geology*, 27, 805–825.

Liu, F. L., Xu, Z. Q., & Liou, J. G. (2004). Tracing the boundary between UHP and HP metamorphic slices in the southwestern Sulu terrane, eastern China:
Western Alps and implications for subduction dynamics. *Natural Science Review, 10*, rwad023.

Chopin, C. (1984). Coesite and pure pyrope in high-grade blueschists of the Western Alps: A first record and some consequences. *Contribution to Mineralogy and Petrology, 86*, 107–118.

Chopin, C., Henry, C., & Michard, A. (1991). Geology and petrology of the coesite-bearing terrain, Dora-Maira massif, Western Alps. *European Journal of Mineralogy, 3*, 263–291.

Cordey, F., & Bailly, A. (2007). Alpine ocean seafloor spreading and onset of pelagic sedimentation: New radiolarian data from the Chenaillet-Mont-genèvre ophiolite (French-Italian Alps). *Geodinamica Acta, 20*, 131–138.

Compagnoni, R., & Rolfo, F. (2003). UHPM Units in the Western Alps. *EMU Notes Mineral, 5*, 13–49.

Compagnoni, R., Rolfo, F., Groppo, C., Hirajima, T., & Turello, R. (2012). Geological map of the ultra-high pressure Brossasco-Isasca unit (Western Alps, Italy). *Journal of Maps, 8*, 465–472.

Compagnoni, R., Elter, G., & Lombardo, B. (1974). Eterogeneità stratigrafica del complesso degli "gneiss minuti" nel massiccio del Gran Paradiso. *Memorie della Società Geologica Italiana, 13*, 227–239.

Corno, A., Mosca, P., Groppo, C., Borghi, A., & Gattiglio, M. (2022). More wide-spread than supposed: Preserved lawsonite in the blueschist-facies ophiolitic bodies from the Albergian Unit (Liguria-Piemonte Zone, Western Alps). *Ofioliti, 47*, 137–154.

Cruciani, G., Franceschelli, M., Musumeci, G., Spani, M. E., & Tiepolo, M. (2013). U-Pb zircon dating and nature of metavolcanics and metarkoses from the Monte Grigni Unit: New insights on Late Ordovician magmatism in the Variscan belt in Sardinia, Italy. *International Journal of Earth Sciences, 102*, 2077–2096.

Coleman, R. G., & Wang, X. (1995). *Ultrahigh pressure metamorphism* (p. 528). Cambridge University Press.

Dana, D., Iaccarino, S., Schmid, S. M., Petroccia, A., & Michard, A. (2023). Structural and metamorphic evolution of a subducted passive margin: Insights from the Briançonnais nappes of the Western Alps (Ubaye-Maira valleys, France-Italy). *Swiss Journal of Geosciences, 116*, 18.

De La Roche, H., Leterrier, J., Grandclaude, P., & Marchal, M. (1980). A classification of volcanic and plutonic rocks using R₁R₂-diagram and major element analyses—Its relationships with current nomenclature. *Chemical Geology, 29*, 183–210.

Dickinson, W. R., & Gehrels, G. E. (2009). Use of U-Pb ages of detrital zircons to infer maximum depositional ages of strata: A test against a Colorado Plateau Mesozoic database. *Earth and Planetary Science Letters, 288*, 115–125.

Ellenberger, F. (1958). Etude géologique du Pays de Vanoise (Savoie). Paris: Mémoires de la Carte Géologique de la France, Imprimerie Nationale. p. 561.

Elter, F. M., Gaggero, L., Mantovani, F., Pandeli, E., & Costamagna, L. C. (2020). The Atlas-East Variscan-Elbe shear system and its role in the formation of the pull-apart Late Palaeozoic basins. *International Journal of Earth Sciences, 109*, 739–760.

Epard, J.-L., & Steck, A. (2008). Structural development of the Tso Morari ultra-high pressure nappe of the Ladakh Himalaya. *Tectonophysics, 451*, 242–264.

Ewing, T. A., Rubatto, D., Lemke, K., & Hermann, J. (2023). Timescales and mechanisms of felsic lower continental crust formation: Insights from U-Pb geochronology of detrital zircon (Malenco Unit, eastern Central Alps). *Lithos, 456–457*, 107286.

Fielding, C. R. (2021). Late Palaeozoic cyclothem—A review of their stratigraphy and sedimentology. *Earth-Science Reviews, 217*, 103612.

Forno, M. G., Fubelli, G., Gattiglio, M., Taddia, G., & Ghignone, S. (2022). Object-based geomorphological mapping: Application on an Alpine deep-seated gravitational slope deformation contest (Germanasca Valley, Western Alps—Italy). *Applied Sciences, 12*, 778.

Forster, M. A., & Lister, G. S. (2005). Several distinct tectono-metamorphic slices in the Cycladic eclogite-blueschist belt, Greece. *Contribution to Mineralogy and Petrology, 150*, 523–545.

Franchi, S. (1911). Il Retico quale zona di transizione fra la Dolomia principale ed il Lias a "facies piemontese"-calcescisti con Belemniti e pietre verdi - nell'alta Valle di Susa. *Bollettino del Reale Comitato Geologico d'Italia, XLI(3)*, 1–37.

Fréville, K., Trap, P., Vanardois, J., Melleton, J., Faure, M., Bruguier, O., Pojoul, M., & Lach, P. (2022). Carboniferous-Permian tectono-metamorphic evolution

of the Pelvoux Massif (External Crystalline Massif, Western Alps), with discussion on flow kinematics of the Eastern-Variscan Shear Zone. *BSGF Earth Science Bulletin, 193*, 13.

García-Arias, M., Díez-Montes, A., Villaseca, C., & Blanco-Quintero, I. F. (2018). The Cambro-Ordovician Ollo de Sapo magmatism in the Iberian Massif and its Variscan evolution: A review. *Earth-Science Reviews, 176*, 345–372.

Gasco, I., Gattiglio, M., & Borghi, A. (2011). Lithostratigraphic setting and P-T metamorphic evolution for the Dora-Maira Massif along the Piedmont Zone boundary (middle Susa Valley, NW Alps). *International Journal of Earth Sciences, 100*, 1065–1085.

Ghignone, S., Balestro, G., Gattiglio, M., & Borghi, A. (2020). Structural evolution along the Susa Shear Zone: The role of a first-order shear zone in the exhumation of meta-ophiolite units (Western Alps). *Swiss Journal of Geosciences, 113*, 17.

Ghignone, S., Borghi, A., Balestro, G., Castelli, D., Gattiglio, M., & Groppo, C. (2021). HP tectono-metamorphic evolution of the Internal Piedmont Zone in Susa Valley (Western Alps): New petrologic insight from garnet+chloritoid-bearing micaschists and Fe-Ti metagabbro. *Journal of Metamorphic Geology, 39*, 391–416.

Gilotti, J. A. (2013). The realm of ultrahigh-pressure metamorphism. *Elements, 9*, 255–260.

Gilotti, J. A., McClelland, W. C., Schorn, S., Compagnoni, R., & Coble, M. A. (2023). Provenance, protolith and metamorphic ages of jadeite-bearing orthogneiss and host paragneiss at Tavagnasco, the Sesia Zone, Lower Aosta Valley, Italy. *European Journal of Mineralogy, 35*, 645–658.

Glodny, J., & Ring, U. (2022). The Cycladic Blueschist Unit of the Hellenic subduction orogen: Protracted high-pressure metamorphism, decompression and reimbrication of a diachronous nappe stack. *Earth-Science Reviews, 224*, 103883.

Grasemann, B., Huet, B., Schneider, D. A., Rice, H. N., Lemonnier, N., & Tschegg, C. (2018). *Geological Society of America Bulletin, 130*, 238–262.

Groppo, C., Ferrando, S., Gilio, M., Botta, S., Nosenzo, F., Balestro, G., Festa, A., & Rolfo, F. (2019). What's in the sandwich? New P-T constraints for the (U) HP nappe stack of southern Dora-Maira Massif (Western Alps). *European Journal of Mineralogy, 31*, 665–683.

Handy, M. R., Schmid, S. M., Bousquet, R., Kissling, E., & Bernoulli, D. (2010). Reconciling plate-tectonic reconstructions of Alpine Tethys with the geological–geophysical record of spreading and subduction in the Alps. *Earth-Science Reviews, 102*, 121–158.

Henry, C., Michard, A., & Chopin, C. (1993). Geometry and structural evolution of ultra-high pressure and high pressure rocks from the Dora-Maira massif, western Alps, Italy. *Journal of Structural Geology, 15*, 965–981.

Horstwood, M. S. A., Košler, J., Gehrels, G., Jackson, S. E., Mc, L. N., Paton, C., Pearson, N. J., Sircombe, K., Sylvester, P., Vermeesch, P., Bowring, J. F., Condon, D. J., & Schoene, B. (2016). Community-derived standards for LA-ICP-MS U-(Th-) Pb geochronology—Uncertainty propagation, age interpretation and data reporting. *Geostandards and Geoanalytical Research, 40*, 311–332.

Hoskin, P.W.O., & Schaltegger, U (2003) The composition of zircon and igneous and metamorphic petrogenesis. In: Hanchar, J.M., & Hoskin, P.W.O. (eds) Zircon. Mineralogical Society of America, Washington, 53, 27–62.

Jackson, S. E., Pearson, N. J., Griffin, W. L., & Belousova, E. A. (2004). The application of laser ablation-inductively coupled plasma-mass spectrometry to in situ U-Pb zircon geochronology. *Chemical Geology, 211*, 47–69.

Jannin, P., & Magri, F. (2017). *Antiche miniere delle Alpi Cozie. Guida storico-escursinistica (volume 2)* (p. 350). Alzani Editore.

Le Bayon, B., & Ballèvre, M. (2006). Deformation history of a subducted continental crust (Gran Paradiso, Western Alps): Continuing crustal shortening during exhumation. *Journal of Structural Geology, 28*, 793–815.

Le Maitre, R. W. (2002). *Igneous rocks. A classification and glossary of terms*. Cambridge: Cambridge University Press.

Lemoine, M., & Trümpy, R. (1987). Pre-oceanic rifting in the Alps. *Tectonophysics, 133*, 305–320.

Liu, F. L., Gerdes, A., & Xue, H. M. (2009). Differential subduction and exhumation of crustal slices in the Sulu HP-UHP metamorphic terrane: Insights from mineral inclusions, trace elements, U-Pb and Lu-Hf isotope analyses of zircon in orthogneiss. *Journal of Metamorphic Geology, 27*, 805–825.

Liu, F. L., Xu, Z. Q., & Liou, J. G. (2004). Tracing the boundary between UHP and HP metamorphic slices in the southwestern Sulu terrane, eastern China:
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Manzotti, P., Schiavi, F., Nosenzo, F., Pitra, P., & Ballèvre, M. (2022). A journey towards the forbidden zone: A new cold UHP unit in the Dora-Maira Massif (Western Alps). *Contributions to Mineralogy and Petrology*, **177**, 59.

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Mattirolo, E., Novarese, V., Franchi, S., & Stella, A. (1913). Carta Geologica d'Italia alla scala 1:100.000, Foglio 67 Pinerolo. Geological Survey of Italy, Roma.

Mattirolo, E., Novarese, V., Franchi, S., & Stella, A. (1951). Carta Geologica d'Italia alla scala 1:100.000, Foglio 67 Pinerolo. Geological Survey of Italy, Roma.

McDonough, W. F., & Sun, S. S. (1995). The composition of the Earth. *Chemical Geology*, **120**, 223–253.

Mertz, J. D., & Siddans, A. W. B. (1985). Finite strain states, quartz textures and the significance of lineation in permcarboniferous metasediments of the Dora Maira Massif, Val Germanasca, Italy. *Tectonophysics*, **118**, 61–73.

Michard, A. (1967). *Etudes Géologiques dans les Zones Internes des Alpes Cottiniennes*. Paris: CNRS éditions. available online at https://tel.archives-ouvertes.fr/tel-00802836.

Michard, A., Chopin, C., & Henry, C. (1993). Contraction versus extension in the exhumation of the Dora Maira massif, western Alps, Italy. *Tectonophysics*, **221**, 173–193.

Michard, A., Schmid, S. M., Lahfid, A., Ballèvre, M., Manzotti, P., Chopin, C., Iaccarino, S., & Dana, D. (2022). The Maira-Sampeyre and Val Grana allochthons (south Western Alps): Review and new data on the tectonometamorphic evolution of the Briançonnais distal Margin. *Swiss Journal of Geosciences*, **115**, 19.

Navidad, M., Castiñeiras, P., Casas, J. M., Liesa, M., Belousova, E., Proenza, J., & Aiglsperger, T. (2018). Ordovician magmatism in the Eastern Pyrenees: Implications for the geodynamic evolution of northern Gondwana. *Lithos*, **314–315**, 479–496.

Nosenzo, F., Manzotti, P., Poujol, M., Ballèvre, M., & Langlade, J. (2022). A window into an older orogenic cycle: P-T conditions and timing of the pre-Alpine history of the Dora-Maira Massif (Western Alps). *Journal of Metamorphic Geology*, **40**, 789–821.

Nosenzo, F., Manzotti, P., & Robyr, M. (2023). H₂O budget and metamorphic re-equilibration in polycyclic rocks as recorded by garnet textures and chemistry. *Lithos*, **452**, 107230.

Novarese, V. (1985). Sul rilevamento eseguito nel 1894 in valle della Germanasca (Alpi Cozie). *Bollettino del Reale Comitato Geologico d'Italia*, **26**, 253–282.

Novarese, V. (1985). Appunti geologici e petrografici sui dintorni di Pinerolo. *Bollettino del Reale Comitato Geologico d'Italia*, **26**, 385–429.

Novarese, V. (1898). I giacimenti di grafite delle Alpi Cozie. *Bollettino del Reale Comitato Geologico d'Italia*, **29**, 3–35.

Novarese, V. (1905). La grafite nelle Alpi piemontesi. *Atti Della Accademia Reale Delle Scienze Di Torino*, **40**, 1–16.

Pantet, A., Epard, J.-L., & Masson, H. (2020). Mimicking Alpine thrusts by passive deformation of synsedimentary normal faults: A record of the Jurassic extension of the European margin (Mont Fort nappe, Penine Alps). *Swiss Journal of Geosciences*, **113**, 13.

Pantet, A., Epard, J.-L., Masson, H., Baumgartner-Mora, C., Baumgartner, P. O., & Baumgartner, L. (2022). Schistes Lustrés in a hyper-extended continental margin setting and reinterpretation of the limit between the Mont Fort and Tsaté nappes (Middle and Upper Penninics, Western Swiss Alps). *Swiss Journal of Geosciences*, **116**, 2.

Paton, C., Hellstrom, J., Paul, B., Woodhead, J., & Hergt, J. (2011). Iolite: Free-ware for the visualisation and processing of mass spectrometric data. *Journal of Analytical Atomic Spectrometry*, **26**, 2508–2518.

Paton, C., Woodhead, J. D., Hellstrom, J. C., Herget, J. M., Greig, A., & Maas, R. (2010). Improved laser ablation U-Pb zircon geochronology through robust downhole fractionation correction. *Geochemistry, Geophysics, Geosystems*, **11**(3), Q0AA06.

Perrone, G., Morelli, M., Cadoppi, P., Tallone, S., & Giardino, M. (2009). A multidisciplinary approach to the study of the fault network in the internal Cottian Alps (Western Alps). *Italian Journal of Geosciences*, **128**, 541–549.

Petroccia, A., & Iaccarino, S. (2022). Metaconglomerate in the Pinerolo Unit (Dora Maira Massif, Western Alps): A key outcrop for Alpine geology and training structural geologists. *International Journal of Earth Sciences*, **111**, 317–319.

Pognante, U. (1979). The Orsiera-Rocciavrè metaphiolitic complex (Italian Western Alps). *Ofioliti*, **4**(2), 183–198.

Pognante, U. (1985). Coronitic reactions and ductile shear zones in eclogitized ophiolite metagabbro, Western Alps, North Italy. *Chemical Geology*, **50**, 99–109.

Rolfo, F., Benna, P., Cadoppi, P., Castelli, D., Favero-Longo, S. E., Giardino, M., & Rossetti, P. (2015). The monviso massif and the Cottian Alps as symbols of the alpine chain and geological heritage in Piemonte, Italy. *Geoheritage*, **7**, 65–84.

Sandrone, R., & Borghi, A. (1992). Zoned garnets in the northern Dora-Maira Massif and their contribution to a reconstruction of the regional metamorphic evolution. *European Journal of Mineralogy*, **4**, 465–474.

Sandrone, R., Cadoppi, P., Sacchi, R., & Vialon, P. (1993). The Dora-Maira massif. In J. F. Raumer & F. Neubauer (Eds.), *Pre-Mesozoic geology in the Alps* (pp. 317–325). Berlin: Springer.

Sandrone, R., Sacchi, R., Cordola, M., & Fontan, D. (1988). Metadiorites in the Dora-Maira polymetamorphic basement (Cottian Alps). *Rendiconti della Società Italiana di Mineralogia e Petrologia*, **43–1**, 593–608.

Schmid, S. M., Fügenschuh, B., Kissling, E., & Schuster, R. (2004). Tectonic map and overall architecture of the Alpine orogeny. *Eclogae Geologicae Helvetiae*, **97**, 93–117.

Schmid, S. M., & Kissling, E. (2000). The arc of the western Alps in the light of geophysical data on deep crustal structure. *Tectonics*, **19**, 62–85.

Schmid, S. M., Kissling, E., Diehl, T., van Hinsbergen, D. J. J., & Molli, G. (2017). Ivrea mantle wedge, arc of the Western Alps, and kinematic evolution of the Alps-Apennines orogenic system. *Swiss Journal of Geosciences*, **110**, 581–612.

Schneider, F. M., Tuan, X., Schurr, B., Mechie, J., Sippl, C., Haberland, C., Minaev, V., Oimahmadvov, I., Gadoev, M., Radjabov, N., Avdybachaev, U., Orunbaev, S., & Negmatullaev, S. (2013). Seismic imaging of subducting continental crust beneath the Pamir. *Earth and Planetary Science Letters*, **375**, 101–112.

Simonetti, M., Carosi, R., Montomoli, C., Cottle, J. M., & Law, R. D. (2020). Transpressive deformation in the Southern European Variscan belt: new insights from the Aiguilles Rouges Massif (Western Alps). *Tectonics*, **39**, e2020TC006153.

Sláma, J., & Košler, J. (2012). Effects of sampling and mineral separation on accuracy of detrital zircon studies. *Geochemistry, Geophysics, Geosystems*, **13**(5), Q05007.

Sláma, J., Košler, J., Condon, D. J., Crowley, J. L., Gerdes, A., Hanchar, J. M., & Whitehouse, J. M. (2008). Plesovice zircon—A new natural reference material for U-Pb and Hf isotopic microanalysis. *Chemical Geology*, **249**, 1–35.
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Manzotti, P., Schiavi, F., Nosenzo, F., Pitra, P., & Ballèvre, M. (2022). A journey towards the forbidden zone: A new cold UHP unit in the Dora-Maira Massif (Western Alps). *Contributions to Mineralogy and Petrology*, **177**, 59.

Marthaler, M., Fudral, S., Deville, E., & Rampnoux, J.-P. (1986). Mise en évidence du Crétacé supérieur dans la couverture septentrionale de Dora-Maira, région de Suse, Italie (Alpes occidentales). Conséquences paléogéographiques et structurales. *Comptes-Rendus de l'académie des Sciences de Paris*, **II**, 302, 91–96.

Mattirolo, E., Novarese, V., Franchi, S., & Stella, A. (1913). Carta Geologica d'Italia alla scala 1:100.000, Foglio 67 Pinerolo. Geological Survey of Italy, Roma.

Mattirolo, E., Novarese, V., Franchi, S., & Stella, A. (1951). Carta Geologica d'Italia alla scala 1:100.000, Foglio 67 Pinerolo. Geological Survey of Italy, Roma.

McDonough, W. F., & Sun, S. S. (1995). The composition of the Earth. *Chemical Geology*, **120**, 223–253.

Mertz, J. D., & Siddans, A. W. B. (1985). Finite strain states, quartz textures and the significance of lineation in permcarboniferous metasediments of the Dora Maira Massif, Val Germanasca, Italy. *Tectonophysics*, **118**, 61–73.

Michard, A. (1967). *Etudes Géologiques dans les Zones Internes des Alpes Cottiniennes*. Paris: CNRS éditions. available online at https://tel.archives-ouvertes.fr/tel-00802836.

Michard, A., Chopin, C., & Henry, C. (1993). Contraction versus extension in the exhumation of the Dora Maira massif, western Alps, Italy. *Tectonophysics*, **221**, 173–193.

Michard, A., Schmid, S. M., Lahfid, A., Ballèvre, M., Manzotti, P., Chopin, C., Iaccarino, S., & Dana, D. (2022). The Maira-Sampeyre and Val Grana allochthons (south Western Alps): Review and new data on the tectonometamorphic evolution of the Briançonnais distal Margin. *Swiss Journal of Geosciences*, **115**, 19.

Navidad, M., Castiñeiras, P., Casas, J. M., Liesa, M., Belousova, E., Proenza, J., & Aiglsperger, T. (2018). Ordovician magmatism in the Eastern Pyrenees: Implications for the geodynamic evolution of northern Gondwana. *Lithos*, **314–315**, 479–496.

Nosenzo, F., Manzotti, P., Poujol, M., Ballèvre, M., & Langlade, J. (2022). A window into an older orogenic cycle: P-T conditions and timing of the pre-Alpine history of the Dora-Maira Massif (Western Alps). *Journal of Metamorphic Geology*, **40**, 789–821.

Nosenzo, F., Manzotti, P., & Robyr, M. (2023). H₂O budget and metamorphic re-equilibration in polycyclic rocks as recorded by garnet textures and chemistry. *Lithos*, **452**, 107230.

Novarese, V. (1985). Sul rilevamento eseguito nel 1894 in valle della Germanasca (Alpi Cozie). *Bollettino del Reale Comitato Geologico d'Italia*, **26**, 253–282.

Novarese, V. (1985). Appunti geologici e petrografici sui dintorni di Pinerolo. *Bollettino del Reale Comitato Geologico d'Italia*, **26**, 385–429.

Novarese, V. (1898). I giacimenti di grafite delle Alpi Cozie. *Bollettino del Reale Comitato Geologico d'Italia*, **29**, 3–35.

Novarese, V. (1905). La grafite nelle Alpi piemontesi. *Atti Della Accademia Reale Delle Scienze Di Torino*, **40**, 1–16.

Pantet, A., Epard, J.-L., & Masson, H. (2020). Mimicking Alpine thrusts by passive deformation of synsedimentary normal faults: A record of the Jurassic extension of the European margin (Mont Fort nappe, Penine Alps). *Swiss Journal of Geosciences*, **113**, 13.

Pantet, A., Epard, J.-L., Masson, H., Baumgartner-Mora, C., Baumgartner, P. O., & Baumgartner, L. (2022). Schistes Lustrés in a hyper-extended continental margin setting and reinterpretation of the limit between the Mont Fort and Tsaté nappes (Middle and Upper Penninics, Western Swiss Alps). *Swiss Journal of Geosciences*, **116**, 2.

Paton, C., Hellstrom, J., Paul, B., Woodhead, J., & Hergt, J. (2011). Iolite: Free-ware for the visualisation and processing of mass spectrometric data. *Journal of Analytical Atomic Spectrometry*, **26**, 2508–2518.

Paton, C., Woodhead, J. D., Hellstrom, J. C., Herget, J. M., Greig, A., & Maas, R. (2010). Improved laser ablation U-Pb zircon geochronology through robust downhole fractionation correction. *Geochemistry, Geophysics, Geosystems*, **11**(3), Q0AA06.

Perrone, G., Morelli, M., Cadoppi, P., Tallone, S., & Giardino, M. (2009). A multidisciplinary approach to the study of the fault network in the internal Cottian Alps (Western Alps). *Italian Journal of Geosciences*, **128**, 541–549.

Petroccia, A., & Iaccarino, S. (2022). Metaconglomerate in the Pinerolo Unit (Dora Maira Massif, Western Alps): A key outcrop for Alpine geology and training structural geologists. *International Journal of Earth Sciences*, **111**, 317–319.

Pognante, U. (1979). The Orsiera-Rocciavrè metaphiolitic complex (Italian Western Alps). *Ofioliti*, **4**(2), 183–198.

Pognante, U. (1985). Coronitic reactions and ductile shear zones in eclogitized ophiolite metagabbro, Western Alps, North Italy. *Chemical Geology*, **50**, 99–109.

Rolfo, F., Benna, P., Cadoppi, P., Castelli, D., Favero-Longo, S. E., Giardino, M., & Rossetti, P. (2015). The monviso massif and the Cottian Alps as symbols of the alpine chain and geological heritage in Piemonte, Italy. *Geoheritage*, **7**, 65–84.

Sandrone, R., & Borghi, A. (1992). Zoned garnets in the northern Dora-Maira Massif and their contribution to a reconstruction of the regional metamorphic evolution. *European Journal of Mineralogy*, **4**, 465–474.

Sandrone, R., Cadoppi, P., Sacchi, R., & Vialon, P. (1993). The Dora-Maira massif. In J. F. Raumer & F. Neubauer (Eds.), *Pre-Mesozoic geology in the Alps* (pp. 317–325). Berlin: Springer.

Sandrone, R., Sacchi, R., Cordola, M., & Fontan, D. (1988). Metadiorites in the Dora-Maira polymetamorphic basement (Cottian Alps). *Rendiconti della Società Italiana di Mineralogia e Petrologia*, **43–1**, 593–608.

Schmid, S. M., Fügenschuh, B., Kissling, E., & Schuster, R. (2004). Tectonic map and overall architecture of the Alpine orogeny. *Eclogae Geologicae Helvetiae*, **97**, 93–117.

Schmid, S. M., & Kissling, E. (2000). The arc of the western Alps in the light of geophysical data on deep crustal structure. *Tectonics*, **19**, 62–85.

Schmid, S. M., Kissling, E., Diehl, T., van Hinsbergen, D. J. J., & Molli, G. (2017). Ivrea mantle wedge, arc of the Western Alps, and kinematic evolution of the Alps-Apennines orogenic system. *Swiss Journal of Geosciences*, **110**, 581–612.

Schneider, F. M., Tuan, X., Schurr, B., Mechie, J., Sippl, C., Haberland, C., Minaev, V., Oimahmadvov, I., Gadoev, M., Radjabov, N., Avdybachaev, U., Orunbaev, S., & Negmatullaev, S. (2013). Seismic imaging of subducting continental crust beneath the Pamir. *Earth and Planetary Science Letters*, **375**, 101–112.

Simonetti, M., Carosi, R., Montomoli, C., Cottle, J. M., & Law, R. D. (2020). Transpressive deformation in the Southern European Variscan belt: new insights from the Aiguilles Rouges Massif (Western Alps). *Tectonics*, **39**, e2020TC006153.

Sláma, J., & Košler, J. (2012). Effects of sampling and mineral separation on accuracy of detrital zircon studies. *Geochemistry, Geophysics, Geosystems*, **13**(5), Q05007.

Sláma, J., Košler, J., Condon, D. J., Crowley, J. L., Gerdes, A., Hanchar, J. M., & Whitehouse, J. M. (2008). Plesovice zircon—A new natural reference material for U-Pb and Hf isotopic microanalysis. *Chemical Geology*, **249**, 1–35.
Steck, A., Epard, J., Vannay, J.-C., Hunziker, J., Girard, M., Morard, A., & Robyr, M. (1998). Geological transect across the Tso Morari and Spiti areas: The nappe structures of the Tethys Himalaya. *Eclogae Geologicae Helvetiae*, **91**, 103–121.

Stephan, T., Kroner, U., Romer, R. L., & Rösel, D. (2019). From a bipartite Gondwanan shelf to an arcuate Variscan belt: The early Paleozoic evolution of northern Peri-Gondwana. *Earth-Science Reviews*, **192**, 491–512.

Sue, C., & Tricart, P. (2003). Neogene to ongoing normal faulting in the inner western Alps: A major evolution of the late Alpine tectonics. *Tectonics*, **22**, 1050. https://doi.org/10.1029/2002TC001426

Talavera, C., Montero, P., Bea, F., González Lodeiro, F., & Whitehouse, M. (2013). U-Pb Zircon geochronology of the Cambro-Ordovician metagranites and metavolcanic rocks of central and NW Iberia. *International Journal of Earth Sciences*, **102**, 1–23.

Teipel, U., Eichhorn, R., Loth, G., Rohrmüller, J., Höll, R., & Kennedy, A. (2004). U-Pb SHRIMP and Nd isotopic data from the western Bohemian Massif (Bayerischer Wald, Germany): Implications for Upper Vendian and Lower Ordovician magmatism. *International Journal of Earth Sciences*, **93**, 782–801.

Thiéblemont, D., Jacob, J.-B., Lach, P., Guerrot, C., & Leguérinel M. (2023). First report of an Ediacaran basement in the Western Alps: the Serre Chevalier crystalline unit (Briançonnais domain, France). *BGFG Earth Sciences Bulletin*.

Törnebohm, A. E. (1888). Om fjällproblemet. *Geologiska Föreningens i Stockholm Förhandlingar*, **10**, 328–336.

Vanardois, J., Trap, P., Roger, F., Melleton, J., Marquer, D., Paquette, J.-L., Goncalves, P., Cagnard, F., & Le Bayon, B. (2022). Deformation, crustal melting and magmatism in the crustal-scale East-Variscan Shear Zone (Aiguilles-Rouges and Mont-Blanc massifs, Western Alps). *Journal of Structural Geology*, **163**, 104724.

Vermeesch, P. (2012). On the visualisation of detrital age distributions. *Chemical Geology*, **312–313**, 190–194.

Vermeesch, P. (2018). IsoplotR: A free and open toolbox for geochronology. *Geoscience Frontiers*, **9**, 1479–1493.

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von Raumer, J. F., & Stampfli, G. M. (2018). Ollo de Sapo Cambro-Ordovician volcanics from the Central Iberian basement—A multiphase evolution. *Terra Nova*, **30**, 350–358.

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Steck, A., Epard, J., Vannay, J.-C., Hunziker, J., Girard, M., Morard, A., & Robyr, M. (1998). Geological transect across the Tso Morari and Spiti areas: The nappe structures of the Tethys Himalaya. *Eclogae Geologicae Helvetiae*, 91, 103–121.

Stephan, T., Kroner, U., Romer, R. L., & Rösel, D. (2019). From a bipartite Gondwanan shelf to an arcuate Variscan belt: The early Paleozoic evolution of northern Peri-Gondwana. *Earth-Science Reviews*, 192, 491–512.

Sue, C., & Tricart, P. (2003). Neogene to ongoing normal faulting in the inner western Alps: A major evolution of the late Alpine tectonics. *Tectonics*, 22, 1050. https://doi.org/10.1029/2002TC001426

Talavera, C., Montero, P., Bea, F., González Lodeiro, F., & Whitehouse, M. (2013). U-Pb Zircon geochronology of the Cambro-Ordovician metagranites and metavolcanic rocks of central and NW Iberia. *International Journal of Earth Sciences*, 102, 1–23.

Teipel, U., Eichhorn, R., Loth, G., Rohrmüller, J., Höll, R., & Kennedy, A. (2004). U-Pb SHRIMP and Nd isotopic data from the western Bohemian Massif (Bayerischer Wald, Germany): Implications for Upper Vendian and Lower Ordovician magmatism. *International Journal of Earth Sciences*, 93, 782–801.

Thiéblemont, D., Jacob, J.-B., Lach, P., Guerrot, C., & Leguérinel M. (2023). First report of an Ediacaran basement in the Western Alps: the Serre Chevalier crystalline unit (Briançonnais domain, France). *BGFG Earth Sciences Bulletin*.

Törnebohm, A. E. (1888). Om fjällproblemet. *Geologiska Föreningens i Stockholm Förhandlingar*, 10, 328–336.

Vanardois, J., Trap, P., Roger, F., Melleton, J., Marquer, D., Paquette, J.-L., Goncalves, P., Cagnard, F., & Le Bayon, B. (2022). Deformation, crustal melting and magmatism in the crustal-scale East-Variscan Shear Zone (Aiguilles-Rouges and Mont-Blanc massifs, Western Alps). *Journal of Structural Geology*, 163, 104724.

Vermeesch, P. (2012). On the visualisation of detrital age distributions. *Chemical Geology*, 312–313, 190–194.

Vermeesch, P. (2018). IsoplotR: A free and open toolbox for geochronology. *Geoscience Frontiers*, 9, 1479–1493.

Vialon, P. (1966). *Etude géologique du massif cristalline Dora-Maira, Alpes Cottiennes Internes, Italie*. Grenoble: Travaux du Laboratoire de Géologie de la Faculté des Sciences de Grenoble, Mémoires. Accessible online at https://hal.archives-ouvertes.fr/tel-00723197

Vialon, P. (1961). Présence d'une discordance à affinités saaliennes dans le massif de Dora-Maira (Alpes cottiennes piémontaises). *Compte Rendus de l'Académie des Sciences de Paris*, 253, 1820–1822.

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