Third party funded individual grant
Acronym: PAPHSANIAS
Start date : 15.04.2017
End date : 31.03.2018
Andesite magmas at active continental margins may form due to assimilation-fractional crystallization processes from basaltic mantle melts or due to direct partial melting of unusual mantle rocks resulting, for example, from mixing of sediment melts with peridotite. Magmas of the Aegean Arc indicate a reaction of the melts with the crust during the ascent as well as a strong input of sediment into the melting zone of the mantle wedge. These different mixing processes are difficult to define in most rocks and require detailed studies of melt (glass) and mineral compositions. Thus, submarine lavas are best suited for a study of andesite formation because melts are quenched and their composition including volatile contents can be determined. The volcanoes of the western Aegean mainly erupted effusive lavas in domes and flows rather than showing explosive activity. We propose a cruise to the westernmost submarine volcano Paphsanias of the Aegean Arc that has not been studied petrologically and geochemically. We suggest studying and sampling this volcano using an ROV that will give us stratigraphic control of the samples. The ROV dives will allow determining the relative abundance of lavas and volcaniclastic rocks and yield insights into the apparently different magma ascent and eruption processes in the western volcanoes. Given the young age of the Paphsanias volcano the crater may also show hydrothermal activity that we will be able to observe and sample using the ROV.Andesite magmas at active continental margins may form due to assimilation-fractional crystallization processes from basaltic mantle melts or due to direct partial melting of unusual mantle rocks resulting, for example, from mixing of sediment melts with peridotite. Magmas of the Aegean Arc indicate a reaction of the melts with the crust during the ascent as well as a strong input of sediment into the melting zone of the mantle wedge. These different mixing processes are difficult to define in most rocks and require detailed studies of melt (glass) and mineral compositions. Thus, submarine lavas are best suited for a study of andesite formation because melts are quenched and their composition including volatile contents can be determined. The volcanoes of the western Aegean mainly erupted effusive lavas in domes and flows rather than showing explosive activity. We propose a cruise to the westernmost submarine volcano Paphsanias of the Aegean Arc that has not been studied petrologically and geochemically. We suggest studying and sampling this volcano using an ROV that will give us stratigraphic control of the samples. The ROV dives will allow determining the relative abundance of lavas and volcaniclastic rocks and yield insights into the apparently different magma ascent and eruption processes in the western volcanoes. Given the young age of the Paphsanias volcano the crater may also show hydrothermal activity that we will be able to observe and sample using the ROV.