Azores Plateau - Cruise No. M128 - July 2 - July 27, 2016 - Ponta Delgada (Azores, Portugal) - Ponta Delgada (Azores, Portugal) (English)

The research program of cruise M128 Azores Plateau mainly aimed at improving our understanding of the igneous and tectonic processes that occur during the initial emplacement of large igneous plateaus and the subsequent interaction between intraplate volcanism and ultraslow rifting. The sampling program targeted the oldest and youngest igneous volcanic edifices in the Azores to better constrain the age of the submarine Plateau and the processes that led to changes in the magmatic activity. During the cruise, a total of 70 TV grab stations (63 containing samples) and 19 successful ROV dives resulted in more than 330 rock samples and more than 435 biological specimens. The combination of bathymetric maps (1980 km hydroacoustic profile length) and petrological samples will allow us to better constrain the evolution of rift systems in this tectonically and magmatically active region. A major sampling focus was the ultraslow spreading Terceira Rift axis and west of the islands. Six stratigraphic dive profiles will yield important constraints on the older lavas of the Azores. Combining the geochemical, petrological, volcanological and biological data will provide a unique and detailed picture of the temporal evolution and the origin of magmatism in the Azores. The extremely detailed maps combined with the extensive sampling will allow to determine the extent to which the local tectonic processes influenced the formation and ascent of melts. The macrofauna samples will yield detailed information on the function of the Azores Plateau as a bathymetric swell in the Central Atlantic Ocean.