Analysis of multiscalar, brittle to ductile structural features aiming at unraveling fundamental structural processes

We study fundamental structural geological processes through a multidisciplinary and multiscale approach that combines field observations and geological mapping with multiscalar analytical and modelling procedures, tectonic considerations and balanced cross sections with the goal to shed light on the processes that steer the deformation of geological materials. We provide important scientific results, with feasible implication for the professional activities.

Paleostress inversion studies aim at reconstructing the stress field evolution of a region through time based on the study of appropriate brittle structural evidence found in rocks (fractures, joints, veins, dykes, stylolites, faults, folds). The assumption is that tectonic stresses from the past have left traces in the rocks in the form of strain.

The intrinsic importance of this approach is that it represents a step towards quantification of geological processes. We have engaged on studies dealing with deformational processes observed in the Southern European Alps (Valsugana and Belluno Thrust, Foiana Line, Cima Marana Thrust, Trento-Cles Line), the Ligurian Alps (Voltri Group), the Northern Apennines (Elba Island and western Tuscany region), the Central Apennines (Amatrice Basin, Lazio Magmatic Province), and the Southern Apennines (the Gargano Promontory, Mattinata Line), Norway, Oman, Thracia (Kavala-Xanthi Line), South Africa, Namibia, Vietnam, Mozambique, Finland, Norway, Sweden, Argentina, central Iran (Kuh-e-Sarhangi Fault, Kuh-E-Faghan Fault), the north Victoria Land in Antarctica (McMurdo Volcanic Group).

Selected references

- Selli L. (1991): Strutture compressive medio-triassiche e alpine nell'area del Passo Valles (Dolomiti). Rendiconti della Società Geologica Italiana, 14, 149-154.

- Prosser G. and Selli L. (1991): Thrusts of the Mezzocorona- Mendola Pass area (Southern Alps, Italy): structural analysis and kinematic reconstruction. Bollettino della Società Geologica Italiana, 110, 805-821.

- Basson I. and Viola G. (2003): Structural overview of selected Group II kimberlite dyke arrays in South Africa: implications for kimberlite emplacement mechanisms. South African Journal of Geology, 106, 4, 375-394.

- Viola G., Mancktelow N., Seward D., Meier A. and Martin S. (2003): The Pejo fault system: an example of multiple tectonic activity in the Italian Eastern Alps. GSA Bulletin, 115, 5, 515-532.

- Viola G., Odonne F. and Mancktelow N. (2004): Analogue modelling of inverse fault reactivation in strike-slip and transpressive regimes: application to the Giudicarie fault system, Italian eastern Alps. Journal of Structural Geology, 26, 401-418.

- Jelsma H., de Wit M., Thiart C., Dirks, P. Viola G., Basson I. and Anckar E. (2004): Preferential distribution along transcontinental corridors of kimberlites and related rocks of Southern Africa. South African Journal of Geology, 107, 1/2, 301-324.

- Basson I. and Viola G. (2004): Passive kimberlite intrusion into actively dilating dyke-fracture arrays: evidence from fibrous calcite veins and extensional fracture cleavage. Lithos, 76, 283-297.

- Viola G. and Mancktelow N. (2005): From XY tracking to buckling: axial plane cleavage fanning and folding during progressive deformation. Journal of Structural Geology, 27, 409-417.

- Viola G., Andreoli, M., Ben Avraham, Z., Stengel I., and Reshef M. (2005): Offshore mud volcanoes and onland faulting in southwestern Africa: Neotectonic implications and constraints on the regional stress field. Earth and Planetary Science Letters, 231, 147-160.

- Bird, P., Ben Avraham, Z., Schubert, J., Andreoli M. and Viola, G. (2006): Patterns of stress and strain rate in southern Africa. Journal of Geophysical Research, Solid Earth, 111, B08402, doi: 10. 1029/2005JB003882.

- Viola, G., Mancktelow, N. and Miller J (2006): Cyclic frictional-viscous slip oscillations along the base of an advancing nappe complex: Insights into brittle-ductile nappe emplacement mechanisms from the Naukluft Nappe Complex, Central Namibia. Tectonics, 25, TC3016, doi: 10.1029/2005TC001939.

- Wilson, C.J.L., Russel-Head D.S., Kunze K. and Viola G. (2007): The analysis of quartz c-axis fabrics using a modified optical microscope. Journal of Microscopy, 227, 30-41.

- Miller, J.A., Viola, G. and Mancktelow, N. (2008): Oxygen, carbon and strontium isotope constraints on the mechanisms of nappe emplacement and fluid rock interaction along the subhorizontal Naukluft Thrust, central Namibia. Journal of the Geological Society of London, 165, 739-753.

- Viola G. (2008): Ductile and brittle deformation history of the Laxemar-Simpevarp area; an independent analysis based on local and regional constraints. SKB R-08-124. Svensk Kärnbränslehantering AB. Available on line from

- Viola, G., Venvik Ganerød G. and Wahlgren, C.-H. (2009): Unravelling 1.5 Gyr of brittle deformation history in the Laxemar-Simpevarp area, SE Sweden: a contribution to the Swedish site investigation study for the disposal of highly radioactive nuclear waste. Tectonics, 28, TC5007, doi:10.1029/2009TC002461.

- Saintot, A., Stephens, M.B., Viola, G. and Nordgulen, Ø. (2011): Brittle tectonic evolution and paleostress field reconstruction in the southwestern part of the Fennoscandian Shield, Forsmark, Sweden. Tectonics, 30, TC4002, doi:10.1029/2010TC002781.

- Dufréchou. G., Odonne, F. and Viola, G. (2011): Analogue models of second order faults genetically linked to a circular strike-slip fault system. Journal of Structural Geology, 33, 1193-1205.

- Viola, G., Kounov, A., Andreoli, M. and Mattila, J. (2012). Brittle tectonic evolution along the western margin of South Africa: more than 500 Myr of continued reactivation. Tectonophysics, 514, 93-114.

- Torgersen, E. and Viola, G. (2014): Structural and temporal evolution of a reactivated brittle-ductile fault: Part I. Fault architecture, strain localization mechanisms and deformation history. Earth and Planetary Science Letters, 407, 205-220.

- Mattila, J. and Viola, G. (2014): New constraints on 1.7 Gyr of brittle tectonic evolution in southwestern Finland derived from a structural study at the site of a potential nuclear waste repository (Olkiluoto Island). Journal of Structural Geology, 67, 50-74.

- Scheiber, T., Viola, G., Bingen, B., Peters, M. and Solli, A. (2015): Multiple reactivation and strain localization along a Proterozoic orogen-scale deformation zone: the Kongsberg-Telemark boundary of southern Norway revisited. Precambrian Research, 265, 78-103.

- Kjøll, H.J., Viola, G., Menegon, L. and Sørensen, B.E. (2015): Brittle-viscous deformation of vein quartz under fluid-rich low greenschist facies conditions. Solid Earth, 6, 681-669.

- Scheiber, T., Fredin, O., Viola, G., Jarna, A., Gasser, D and Łapińska-Viola, R. (2015): Manual extraction of bedrock lineaments from high resolution LiDAR data: methodological bias and human perception. GFF, 137, 4, 362-372, doi: 10.1080/11035897.2015.1085434

- Scheiber, T., Viola, G., Wilkinson, C.M., Ganerød, M., Skår, Ø. and Gasser, D. (2016): Direct 40Ar/39Ar dating of Late-Ordovician and Silurian brittle faulting in the southwestern Norwegian Caledonides. Terra Nova, 28, 5, 374-382.

- Traforti, A., Massironi, M., Bistacchi, A., Zampieri, D. and Viola, G.(2018): Slip-tendency analysis as a tool to constrain the mechanical properties of T anisotropic rocks. Journal of Structural Geology, 117, 136-147, doi: 10.1016/j.jsg.2018.09.001.

- Fransson, Å., Viola, G. and Lönnqvist, M. (2019): Rock mechanical modelling of the Bentonite Rock Interaction Experiment, Äspö Hard Rock Laboratory, Sweden. International Journal of Rock Mechanics and Mining Sciences, 113, 255-267.

- Carlini, M., Viola, G., Mattila, J. and Castellucci, L. (2019): The role of mechanical stratigraphy on the refraction of strike-slip faults. Solid Earth, 10, 343-356, doi: 10.5194/se-10-343-2019.

- Mazzarini, F., Musumeci, G., Viola, G., Mattila, J. and Garofalo, P.S. (2019): Structural and lithological control on fluid circulation, dilation and ore mineralization (Rio Albano Mine, Island of Elba, Italy). Journal of Structural Geology, 126, 210-230, doi: 10.1016/j.jsg.2019.06.012.

- Vignaroli G., Berardi G., Billi A., Kele S., Rossetti F., Soligo M., Bernasconi S.M. (2016). Tectonics, hydrothermalism, and paleoclimate recorded by Quaternary travertines and their spatio-temporal distribution in the Albegna basin, Italy: Insights on Tyrrhenian margin neotectonics. Lithosphere, 8 (4): 335-358, doi:10.1130/L507.1.

- Berardi G., Vignaroli G., Billi A., Rossetti F., Soligo M., Kele S., Baykara M.O., Bernasconi S.M., Castorina F., Tecce F., Shen C.C. (2016). Growth of a Pleistocene giant carbonate vein and nearby thermogene travertine deposits at Semproniano, southern Tuscany, Italy: estimate of CO2 leakage. Tectonophysics, 690, 219-239, doi: 10.1016/j.tecto.2016.04.014.

- Vignaroli G., Urru G., Rossetti F., Belardi G., Piaggi L. (2017). Tectonic structures and commercial compartments in active quarrying: a case history from the northern Italy. Bulletin of Engineering Geology and the Environment, 76, 477–496, doi: 10.1007/s10064-016-0925-z.

- Vignaroli G., Balsamo F., Giordano G., Rossetti F., Storti F. (2015). Miocene-to-Quaternary oblique rifting signature in the Western Ross Sea from fault patterns in the McMurdo Volcanic Group, north Victoria Land, Antarctica. Tectonophysics, 656, 74-90, doi:10.1016/j.tecto.2015.05.027.

- Vignaroli G., Aldega L., Balsamo F., Billi A., De Benedetti A.A., De Filippis L., Giordano G., Rossetti F. (2015). A way to hydrothermal paroxysm, Colli Albani Volcano, Italy. GSA Bulletin, 127, 672-687,. doi: 10.1130/B31139.1.

- Calzolari G., Della Seta M., Rossetti F., Nozaem R., Vignaroli G., Cosentino D., Faccenna C. (2015). Geomorphic signal of active faulting at the northern edge of Lut Block: Insights on the kinematic scenario of Central Iran. Tectonics, 35, doi:10.1002/2015TC003869.

- Vignaroli G., Pinton A., De Benedetti A.A., Giordano G., Rossetti F., Soligo M., Berardi G. (2013). Structural compartmentalization of a geothermal system, the Torre Alfina field (central Italy). Tectonophysics, 608, 482-498, doi:10.1016/j.tecto.2013.08.040.

- Nozaem R., Mohajjel M., Rossetti F., Della Seta M., Vignaroli G., Yassaghi A., Salvini F., Elyasi M. (2013). Post-Neogene right-lateral strike-slip tectonics at the north-western edge of the Lut Block (Kuh-e-Sarhangi Fault), Central Iran. Tectonophysics, 589, 220-233.

- Vignaroli G., Minelli L., Rossetti F., Balestrieri M.L., Faccenna C. (2012). Miocene thrusting in the eastern Sila Massif: Implication for the evolution of the Calabria-Peloritani orogenic wedge (southern Italy). Tectonophysics, 538-540, 105-119, doi:10.1016/j.tecto.2012.03.011.

- Vignaroli G., Faccenna C. and Rossetti F. (2009). Retrogressive fabric development during exhumation of the Voltri Massif (Ligurian Alps, Italy): arguments for an extensional origin and implications for the Alps-Apennine linkage. International Journal of Earth Sciences, 98, 1077-1093, doi: 10.1007/s00531-008-0305-4.

- Vignaroli G., Mancini M., Brilli M., Bucci F., Cardinali M., Giustini F., Voltaggio M., Yu T.-L., Shen C.-C. (2020). Spatial-temporal evolution of extensional faulting and fluid circulation in the Amatrice Basin (central Apennines, Italy) during the Pleistocene. Frontiers in Earth Science – Structural Geology and Tectonics, doi: 10.3389/feart.2020.00130.