Dr Rousakis main research fields are Marine Geology, Sedimentology and Geophysics, Holocene Geology, Sea level changes and sediment sequences/facies, Geotechnical properties of sediments, Slope stability, Cold seeps and Mud volcanoes, Neotectonics – Active faulting – Marine Paleoseismology, Submarine Volcanism Deep sea habitat mapping, Deep sea observatories, Paleoceanography, Environmental Monitoring, Underwater Geoarchaeology. Applied research related to submarine surveys (cables and pipeline route surveys, artiphicial reefs, offshore windparks, submarine groundwater discharges etc).

During the last 34 years in the Institute of Oceanography of HCMR, he has been involved in a variety of research projects, most of which have been funded by the EU (CINCS, MATER, METROMED ASSEM, ANAXIMANDER, 3HAZ CORINTH, ΚM3NeT, SEAHELLARC, MEDECOS, CORAL FISH, EMSO-HELLENIC SITE, AEGEAN EXPLORATIONS, TERRA SUBMERSA, DISPERSE, EMODNET GEOLOGY etc.). He has been chief scientist of more than 23 national and international research cruises onboard oceanographic vessels.

He has published more than 32 scientific papers in peer-reviewed journal and more than 100 chapter books, original contributions in international and Greek conferences proceedings with a total citation record of 601/h-index 15.