Marine Hazards and Geohazards

Some 20 years ago the Institute of Oceanography launched a long-term, strategic plan with the objective to map, study and characterize the submarine active faults and landslides. The main aim of this project is to detect and highlight the offshore areas where marine geohazards have occurred and may occur in the future and may generate disastrous phenomena, including the generation of tsunamis.

Swath bathymetry coverage and seismic profiles in the Aegean, Ionian and Libyan Seas
Fig. 1. Swath bathymetry coverage and seismic profiles in the Aegean, Ionian and Libyan Seas

Mapping of marine geohazards requires the acquisition, processing, analysis and interpretation of swath bathymetry, side scan sonar and seismic profiling data (Fig. 1). Reprocessing and evaluation of the available data-sets in the data base of the Institute are in progress along with the work on new data acquired during the research cruises.

The first, comprehensive map of the offshore fault network and interpretation of the kinematics of the faults in Aegean Sea and the Hellenic Trench has been recently published (Fig. 2). This is an ongoing effort aiming at continuous updating and refining the offshore fault map and understanding the kinematic regime and active tectonic deformation processes.

Offshore active faults, volcanoes of the Hellenic Volcanic Arc and Plio-Quaternary sedimentary basins
Fig. 2. Offshore active faults, volcanoes of the Hellenic Volcanic Arc and Plio-Quaternary sedimentary basins in the Aegean (from Sakellariou & Tsampouraki-Kraounaki, 2018)

The spatial and temporal distribution of the volcanic/hydrothermal activity in the South Aegean and their relationship with the active faulting and seismicity remain among the foci of research on marine geohazards.
Systematic mapping of submarine landslides, identification of areas prone to landslides and potential tsunami source areas are among the research priorities of the IO. Recent advances in bathymetric coverage and high-resolution seismic profiling, side scan sonar data and sediment coring from various areas are used for the interpretation of mass transport deposits and their potential relationship with known tsunamis in the past. Elaboration of various scenarios for the generation and propagation of tsunamis will be based on realistic simulations and studied source areas.