Formation and evolution of magmas due to sediment subduction: a case study of the submarine Paphsanias volcano, Aegean arc

• Applicant: Professor Dr. Karsten Matthias Haase
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: from 2017 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 378188864

The effects of sediment recycling on the formation and evolution of magmas at subduction zones and on the growth of the continental crust are poorly known. Melts of subducted sediments mix into the mantle and cause melting of basaltic or andesitic magmas that are important for the formation of the continental crust. Up to 8 km thick sediment deposits exist at the Aegean arc and signficant portions of these are subducted leading to a strong sediment signature in the arc lavas. One of the westernmost volcanoes of the Aegean arc is the submarine volcano Paphsanias that was found only in 1987 and that apparently was active some 2000 years ago. During cruise Poseidon 512 in April/May 2017 we plan to explore this volcano for the first time using the remotely operated vehicle (ROV) PHOCA and here we apply for the cost of the rental of the ROV. The ROV allows detailed observations and stratigraphic sampling of the lavas and volcaniclastic rocks as well as an understanding of eruptive units and potential hydrothermal activity. We suspect abundant volcanic glasses in the eruptive units of Paphsanias volcano so that the composition of liquids and their volatile contents can be directly determined. This will provide important new insights into the processes of sediment subduction and magma formation, of mixing and degassing as well as of eruption. This project will lead to a better understanding of continental growth and of potential volcanic hazards of the Paphsanias volcano that lies only 50 km SW of Athens.

• DFG Programme: Research Grants