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Giant Garnet Crystals in Wollastonite–Grossularite–Diopside-Bearing Marbles from Tamarispa (NE Sardinia, Italy): Geosite Potential, Conservation, and Evaluation as Part of a Regional Environmental Resource

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Abstract

The wollastonite–garnet–diopside-bearing marbles cropping out in the Migmatite Complex west to the Tamarispa and San Lorenzo villages share a common metamorphic and deformational history with the surrounding migmatite, with metamorphic peak conditions between 650 and 850 °C. Within the marble, there is an interesting and rare garnet mineralization. The peculiar characteristic and geological–cultural and touristic attraction of this geosite is the presence of large garnet crystals (up to 20 cm). The whitish rock matrix is characterized by coarse-grained rock-forming minerals (mainly wollastonite, calcite, diopside and subordinately pectolite, quartz, plagioclase, epidote, apatite, titanite) with a compositional layering and a weak foliation (S2 schistosity), parallel to that of the surrounding gneiss and migmatites. At the outcrop scale, the giant garnet crystals often show a brown core in high relief surrounded by a darker rim with less relief. Under conservation state, the wollastonite–garnet–diopside-bearing marbles show an evident differential alteration with dissolution processes of the matrix and an increasingly pronounced enucleation of the garnet crystals. The Tamarispa outcrop with spectacular giant garnet crystals is here proposed as a new, potential geosite relevant for didactic, cultural, and touristic purposes. Conservation and valorization aspects are discussed within the more general framework of the geological, natural, and environmental resources of the local territory.

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References

  • Advokaat EL, van Hinsbergen DJJ, Maffione M, Langereis CG, Vissers RLM, Cherchi A, Schroeder R, Madani H, Columbu S (2014) Eocene rotation of Sardinia, and the paleogeography of the western Mediterranean region. Earth Planet Sci Lett 401:183–195

    Google Scholar 

  • Agashev AM (2019) Geochemistry of garnet megacrysts from the Mir Kimberlite Pipe (Yakutia) and the nature of protokimberlite melts. Dokl Earth Sci 486:675–678

    Google Scholar 

  • Amoroso G (2002) Trattato di scienza della conservazione dei monumenti. Alinea editrice, Florence

    Google Scholar 

  • Aseeva A, Avchenko O (2020) Unusual Garnet Megacryst with a partly–crystallized melt inclusion from Cenozoic alkali basalts of Shavaryn Tsaram Paleovolcano (Mongolia): a captured material of the Earth’s interior or a ‘melt pocket’. Abstract of the EGU General Assembly 2020

  • Baxter EF, Caddick MJ, Ague JJ (2013) Garnet: common mineral, uncommonly useful. Elements 9:415–419

    Google Scholar 

  • Brandelik A (2009) CALCMIN—An EXCELTM Visual Basic application for calculating mineral structural formulae from electron microprobe analyses. Comput Geosci 35:1540–1551

    Google Scholar 

  • Butlin RN, Yates TJS, Martin W (1995) Comparison of traditional and modern treatments for conserving stone. Methods of evaluating products for the conservation of porous building materials in mon- uments: international colloquium. Italy, Rome, pp 111–119

    Google Scholar 

  • Camaiti M, Benvenuti E, Paciulli L (2011) Formulati a base di poliammidi parzialmente fluorurate e fluoroelastomeri per la protezione e il consolidamento di manufatti lapidei. Arkos Scienza e Restauro 28:29–33

    Google Scholar 

  • Camaiti M, Cerri F, Rescic S, Sacchi B, Tiano P (2002) Ethyl silicate as reinforcing agent for stone materials: laboratory and in situ tests. International Congress on the silicates in the conservative treat- ments, Torino, Italy, pp 137–145

    Google Scholar 

  • Camaiti M, Dei L, Errico V (2006) Consolidation treatment of tuff: in situ polymerization or traditional methods? In: Proceedings of V Int. Conference on Structural Analysis of Historical constructions, New Delhi, India

  • Cao Y, Salvini A, Camaiti M (2017) Oligoamide grafted with perfluoropolyether blocks: a potential protective coating for stone materials. Prog Org Coat 111:164–174

    Google Scholar 

  • Carmignani L, Oggiano G, Barca S, Conti P, Salvadori I, Eltrudis A, Funedda A, Pasci S (2001) Geologia della Sardegna. Note illustrative della Carta Geologica della Sardegna a scala 1:200.000. Mem Soc Geol It 60, pp 283

  • Casini L, Cuccuru S, Maino M, Oggiano G, Tiepolo, (2012) Emplacement of The Arzachena pluton (Corsica–Sardinia batholith) and the geodynamics of incoming Pangaea. Tectonophysics 544–545:31–49

    Google Scholar 

  • Chopin C (1984) Coesite and pure pyrope in high–grade blueschists of the Western Alps: a first record and some consequences. Contrib Mineral Petrol 86:107–118

    Google Scholar 

  • Cnudde V, Dierick M, Vlassenbroeck J, Masschaele B, Lehmann E, Jacobs P, Van Hoorebeke L (2007) Determination of the impregnation depth of siloxanes and ethylsilicates in porous material by neutron radiography. J Cult Herit 8:331–338

    Google Scholar 

  • Columbu S, Lisci C, Sitzia F, Buccellato G (2017) Physical-mechanical consolidation and protection of Miocenic limestone used on Mediterranean historical monuments: the case study of Pietra Cantone (southern Sardinia, Italy). Environ Earth Sci 76(4):148. https://doi.org/10.1007/s12665-017-6455-6

    Article  Google Scholar 

  • Costamagna LG, Elter FM, Gaggero L, Mantovani F (2016) Contact metamorphism in Middle Ordovician arc rocks (SW Sardinia, Italy): new paleogeographic constraints. Lithos 264:577–593

    Google Scholar 

  • Cruciani G, Fancello D, Franceschelli M, Scodina M, Spano ME (2014a) Geothermobarometry of Al–silicate–bearing migmatites from the Variscan chain of NE Sardinia, Italy: a P-T pseudosection approach. Per Mineral 83(1):19–40

    Google Scholar 

  • Cruciani G, Franceschelli M, Foley SF, Jacob DE (2014b) Anatectic amphibole and restitic garnet in some Variscan migmatite from NE Sardinia, Italy: insights into partial melting from mineral trace elements. Eur J Mineral 26:381–395

    Google Scholar 

  • Cruciani G, Franceschelli M, Groppo C (2011) P-T evolution of eclogite–facies metabasite from NE Sardinia, Italy: insights into the prograde evolution of Variscan eclogites. Lithos 121:135–150

    Google Scholar 

  • Cruciani G, Franceschelli M, Groppo C, Oggiano G, Spano ME (2015a) Re–equilibration history and P-T path of eclogites from Variscan Sardinia, Italy: a case study from the medium–grade metamorphic complex. Int J Earth Sci 104:797–814

    Google Scholar 

  • Cruciani G, Franceschelli M, Langone A, Puxeddu M, Scodina M (2015b) Nature and age of pre–Variscan eclogite protoliths from the Low– to Medium-Grade Metamorphic Complex of north–central Sardinia (Italy) and comparisons with coeval Sardinian eclogites in the northern Gondwana context. J Geol Soc 172:792–807

    Google Scholar 

  • Cruciani G, Franceschelli M, Massonne H-J, Musumeci G, Scodina M (2020) Garnet–rich veins in an ultrabasic amphibolite from NE Sardinia, Italy: an example of vein mineralogical re–equilibration during the exhumation of a granulite terrane. Geosciences 10(9):344. https://doi.org/10.3390/geosciences10090344

    Article  Google Scholar 

  • Cruciani G, Franceschelli M, Massonne H-J, Musumeci G, Spano ME (2016) Thermomechanical evolution of the high–grade core in the nappe zone of Variscan Sardinia, Italy: the role of shear deformation and granite emplacement. J Metamorphic Geol 34:321–342

    Google Scholar 

  • Cruciani G, Franceschelli M, Musumeci G, Scodina M (2020b) Geology of the Montigiu Nieddu metamorphic basement, NE Sardinia (Italy). J Maps 16(2):543–551

    Google Scholar 

  • Cruciani G, Franceschelli M, Musumeci G, Spano ME, Tiepolo M (2013) U-Pb zircon dating and nature of metavolcanics and metarkoses from the Monte Grighini Unit: new insights on Late Ordovician magmatism in the Variscan belt in Sardinia, Italy. Int J Earth Sci 102:2077–2096

    Google Scholar 

  • Cruciani G, Franceschelli M, Puxeddu M, Tiepolo M (2018) Metavolcanics from Capo Malfatano, SW Sardinia, Italy: new insight on the age and nature of Ordovician volcanism in the Variscan foreland zone. Geol J 53:1573–1585

    Google Scholar 

  • Cruciani G, Montomoli C, Carosi R, Franceschelli M, Puxeddu M (2015c) Continental collision from two perspectives: a review of Variscan metamorphism and deformation in northern Sardinia. Per Mineral 84:657–699

    Google Scholar 

  • Cussler EL (2009) Diffusion: mass transfer in fluid systems. Cambridge University Press, Cambridge(United Kingdom), p 631

    Google Scholar 

  • Davidson A, Brown GW (2012) ParaloidTM B-2: practical tips for the vertebrate fossil preparatory. Coll Forum 26:99–19

    Google Scholar 

  • De Clercq H, De Witte E (2001) Effectiveness of commercial silicon based water repellents at different application conditions. In: Proceedings of Hydrophobe III - 3rd International Conference on Surface Technology with Water Repellent Agents, Freiburg, Germany, 179–190

  • Doehene E, Price CA (2010) Stone conservation—an overview of current research, 2nd edn. Getty Publications Book Distribution Center, Los Angeles, pp 978-1-60606-046–9

    Google Scholar 

  • Down JL, MacDonald MA, Tetreault J, Williams RS (1996) Adhesive testing at the Canadian Conservation Institute: an evaluation of selected poly (vinyl acetate) and acrylic adhesives. Stud Conserv 41:19–44

    Google Scholar 

  • Elter FM, Musumeci G, Pertusati PC (1990) Late Hercynian shear zones in Sardinia. Tectonophysics 176:387–404

    Google Scholar 

  • Elter FM, Padovano M, Kraus RK (2010) The Variscan HT metamorphic rocks emplacement linked to the interaction between Gondwana and Laurussia plates: structural constraints in NE Sardinia (Italy). Terra Nova 22:369–377

    Google Scholar 

  • Elter FM, Palmeri R (1992) The calc–silicate marble of Tamarispa (NE Sardinia), in: Carmignani, L. Sassi, F.P. (Eds.), Contributions to the Geology of Italy with Special Regards to the Paleozoic Basement, Newsletter 5, Pisa, 117–122

  • Fancello D, Cruciani G, Franceschelli M, Massonne H-J (2018) Trondhjemitic leucosomes in paragneisses from NE Sardinia: geochemistry and PT conditions of melting and crystallization. Lithos 304–307:501–517

    Google Scholar 

  • Ferrero S, Wannhoff I, Laurent O, Yakymchuk C, Darling R, Wunder B, Borghini A, O’Brien PJ (2021) Embryos of TTGs in Gore Mountain garnet megacrysts from water-fluxed melting of the lower crust. Earth Planet Sci Let 569:117058. https://doi.org/10.1016/j.epsl.2021.117058

    Article  Google Scholar 

  • Franceschelli M, Puxeddu M, Cruciani G, Dini A, Loi M (2005) Layered amphibolite sequence in NE Sardinia, Italy: remnant of a pre–Variscan mafic–silicic layered intrusion? Contrib Mineral Petrol 149:164–180

    Google Scholar 

  • Franzoni E, Pigino B, Pistolesi C (2013) Ethyl silicate for surface protection of concrete: performance in comparison with other inorganic surface treatments. Cem Concr Compos 44:69–76

    Google Scholar 

  • Goins ES, Wheeler GS, Wypphski MT (1996) Proceedings of the 8th international congress on deterioration and conservation of stone. vol. III, Berlin, Germany, 1255–1264

  • Hartung RF, Simões LSA, Trouw RAJ, Silva AJCA (2020) Growth mechanism of garnet megaporphyroblasts of the Passos Nappe, Southern Brasília Orogen. Brazil. J South Am Earth Sci 102:102649

    Google Scholar 

  • Helbing H, Tiepolo M (2005) Age determination of Ordovician magmatism in NE Sardinia and its bearing on Variscan basement evolution. J Geol Soc 162:689–700

    Google Scholar 

  • Kim EK, Won J, Do J, Kim SD, Kang YS (2009) Effects of silica nano-particle and GPTMS addition on TEOS-based stone consolidants. J Cult Herit 10:221–241

    Google Scholar 

  • Koob SP (1986) The use of Paraloid B-72 as an adhesive: its application for archaeological ceramics and other materials. Stud Conserv 31:7–14

    Google Scholar 

  • La Russa MF, Barone G, Belfiore CM, Mazzoleni P, Pezzino A (2011) Application of protective products to Noto calcarenite (south-eastern Sicily): a case study for the conservation of stone materials. Environ Earth Sci 62:1263–1272

    Google Scholar 

  • Luo Y, Xiao L, Zhang X (2015) Characterization of TEOS/PDMS/HA nanocomposites for application as consolidant/hydrophobic products on sandstones. J Cult Herit 16:470–478

    Google Scholar 

  • Marchetti M (1999) Il censimento dei “beni geologici.” G. Poli (a cura di), Geositi Testimoni del tempo (Fondamenti per la conservazione del patrimonio geologico), Bologna, pp 69–87

    Google Scholar 

  • Massonne HJ, Cruciani G, Franceschelli M (2013) Geothermobarometry on anatectic melts—a high–pressure Variscan migmatite from northeast Sardinia. Int Geol Rev 55:1490–1505

    Google Scholar 

  • Morimoto N (1988) Nomenclature of Pyroxenes Mineral Petrol 39:55–76

    Google Scholar 

  • Padovano M, Dörr W, Elter FM, Gerdes A (2014) The East Variscan Shear Zone: geochronological constraints from the Capo Ferro area (NE Sardinia, Italy). Lithos 196–197:27–41

    Google Scholar 

  • Price CA (1996) Stone conservation: an overview of current research. Getty conservation institute

  • Rossi P, Oggiano G, Cocherie A (2009) A restored section of the “southern Variscan realm” across the Corsica-Sardinia microcontinent. C R Geoscience 341:224–238

    Google Scholar 

  • Sasse HR, Honsinger D, Schwamborn B (1993) PINS: a new technology in porous stone conservation. In: The conservation of stone and other materials, vol. 2, New York, US, pp 705–716

  • Scodina M, Cruciani G, Franceschelli M, Massonne H-J (2019) Anticlockwise P–T evolution of amphibolites from NE Sardinia, Italy: geodynamic implications for the tectonic evolution of the Variscan Corsica-Sardinia block. Lithos 324:763–775

    Google Scholar 

  • Scodina M, Cruciani G, Franceschelli M, Massonne H-J (2020) Multilayer corona textures in the high–pressure ultrabasic amphibolite of Mt. Nieddu, NE Sardinia (Italy): equilibrium versus disequilibrium. Per Miner 89:169–186

    Google Scholar 

  • Siegesmund S, Weiss T, Vollbrecht A (2002) Natural stone, weathering phenomena, conservation strategies and case studies. Geological society special publications no. 205, The Geological Society, London

    Google Scholar 

  • UNESCO Convention (1972) No. 15511 - MULTILATERAL Convention for the protection of the world cultural and natural heritage. Adopted bythe General Conference of the United Nations Educational, Scientific and Cultural Organization at its seventeenthsession, Paris, 16 November 1972. Registered by the United Nations Educational, Scientific and CulturalOrganization on 9 March 1977.https://whc.unesco.org/en/conventiontext/

  • Vernon RH (2004) A practical guide to rock microstructure. Cambridge University Press, Cambridge (United Kingdom), pp. 594, https://doi.org/10.1017/CBO9780511807206

  • Wheeler G (2005) Alkoxysilane and stone conservation. Getty publica- tion, Los Angeles, pp 83–100

    Google Scholar 

  • Wheeler GS, Fleming SA, Ebersole S (1991) Evaluation of some current treatments for marble. In: Second International Symposium on the Conservation of Monuments in the Mediterranean Basin, Geneva, Ville de Geneve, Museum d'Histoire naturelle & Musee d'art et d'histoire

  • Wheeler GS, Fleming SA, Ebersole S (1992) Comparative strengthening effect of several consolidants on Wallace sandstone and Indiana limestone. In: Seventh International Congress on Deterioration and Conservation of Stone, Lisbon, Portugal, pp 1033–1041

  • Whitney DL, Evans BW (2010) Abbreviations for names of rock–forming minerals. Am Miner 95:185–187

    Google Scholar 

  • Winter JD (2001) An introduction to igneous and metamorphic petrology. Prentice Hall, Upper Saddle River (State of New Jersey, United States), p 697

    Google Scholar 

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Acknowledgements

We thank the Municipality and the Tourist Office of the ProLoco of Budoni and the Museum of the Stazzo and peasant civilization.

Funding

Financial support was provided by Regione Autonoma della Sardegna, L.R. 7/2007, research program “Il blocco Sardo–Corso: area chiave per la ricostruzione della geodinamica varisica” CUP J81G17000110002.

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Authors and Affiliations

  1. Dipartimento di Scienze Chimiche e Geologiche, Università di Cagliari, Cittadella Universitaria, 09042, Monserrato, Italy

    M. Franceschelli, S. Columbu & G. Cruciani

  2. Dipartimento di Scienze della Terra dell’Ambiente e della Vita, Università di Genova, Corso Europa 26, 16132, Genova, Italy

    F. M. Elter

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  1. M. Franceschelli
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  2. S. Columbu
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  3. F. M. Elter
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  4. G. Cruciani
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Correspondence to S. Columbu.

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Franceschelli, M., Columbu, S., Elter, F.M. et al. Giant Garnet Crystals in Wollastonite–Grossularite–Diopside-Bearing Marbles from Tamarispa (NE Sardinia, Italy): Geosite Potential, Conservation, and Evaluation as Part of a Regional Environmental Resource. Geoheritage 13, 96 (2021). https://doi.org/10.1007/s12371-021-00622-3

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