EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Mantle metasomatism recorded upon bimodal chromitites (E. Chalkidiki, Greece): a tool to unravel metasomatic processes

Petros Koutsovitis1, Alkiviadis Sideridis1, Pavlos Tsitsanis2, Federica Zaccarini3, Basilios Tsikouras4, Christoph Hauzenberger5, Tassos Grammatikopoulos6, Luca Bindi7, Giorgio Garuti3, and Konstantin Hatzipanagiotou1
Petros Koutsovitis et al.
  • 1University of Patras (Greece), Univerisity, Department of Geology, Patra, Greece (
  • 2Independent scholar, Makedonias 21, Nea Moudania 63200, Greece
  • 3Department of Applied Geological Sciences and Geophysics, University of Leoben, A-8700 Leoben, Austria
  • 4Faculty of Science, Physical and Geological Sciences, Universiti Brunei Darussalam, Gadong BE 1410, Brunei Darussalam
  • 5NAWI Graz Geocenter, University of Graz, Universitätsplatz 2, Graz 8010, Austria
  • 6SGS Canada Inc., 185 Concession Street, PO 4300, Lakefield, ON K0L 2H0, Canada
  • 7Dipartimento di Scienze della Terra, Università degli Studi di Firenze, I-50121 Florence, Italy

Nea Roda and Gomati ultramafic bodies (east Chalkidiki, north Greece) consist of both Cr- and Al- podiform chromitites, which are highly altered. Their PGE geochemistry and subsequently PGE-mineralogy (PGM) demonstrate abnormal element concentrations with an enrichment in PPGE (Pd, Pt), leading to high Pd/Ir ratios. Secondary PGM and base metal assemblages are dominated by Sb and As, whereas primary phases form sulphides. At a more mature stage, desulphurization of the aforementioned phases led to formation of native metals. Diopside hosted within diopsidite and chromitite show both an alkaline melt- and a fluid- rock interaction, depicted by LREE enrichment. The temperature of the metasomatic fluids was lower than 600oC, as recorded by chlorite and garnet geothermometry. A raise in fluid mobile elements (FME: B, Sb, Li, As, Cs, Pb, U, Ba and Sr) is noted in the whole rock and clinopyroxene analysis. All these characteristics along with the distinctive spinel textures (porous, zoned grains) point to a metasomatic event during subduction that led to the post-magmatic modification of the chromitites and the mantle section causing a LREE, Pb, As, Sb, Pd and Pt enrichment. 

How to cite: Koutsovitis, P., Sideridis, A., Tsitsanis, P., Zaccarini, F., Tsikouras, B., Hauzenberger, C., Grammatikopoulos, T., Bindi, L., Garuti, G., and Hatzipanagiotou, K.: Mantle metasomatism recorded upon bimodal chromitites (E. Chalkidiki, Greece): a tool to unravel metasomatic processes, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9331,, 2022.