Understanding Extreme Geohazards: The Science of the Disaster Risk Management Cycle European Science Foundation Conference November 28 to December 1, 2011, Sant Feliu de Guixols, Spain

Hazards in the Aegean: in-Depth Experiment to Study Tectonic Structure and Seismic Activity

C.R. Ranero (1), R. Urgeles (2), X. Garcia (3), V. Sallares (3), G. Booth-Rea (4), I. Grevemeyer (5), M. Jegen (5), C. Berndt (5), G. Papadopulos (6), F. Vallinatos (7), D. Sakellariou (8)
(1) ICREA at Instituto de Ciencies del Mar (CSIC), Passeig Maritim de la Barceloneta, 37-49, 08003 Barcelona, Spain
(2) Instituto de Ciencias del Mar (CSIC), Passeig Maritim de la Barceloneta, 37-49, 08003 Barcelona, Spain
(3) Unitat de Tecnologia Marina (CSIC), Passeig Maritim de la Barceloneta, 37-49, 08003 Barcelona, Spain
(4) Universidad de Granada, Departamento de Geodinamica, Av. Fuentenueva s/n, E-18071 Granada, Spain
(5) IFM-GEOMAR, Wischhofstr. 1-3. 24148 Kiel, Germany
(6) National Observatory of Athens, P.O. Box 200 48, 118 10 Thissio, Athens, Greece
(7) Technological Educational Institute of Crete, 3 Romanou Str., Chalepa GR-73133 Chania Crete, Greece
(8) Inst. Oceanography, Hellenic Centre for Marine Research, PO Box 712, 19013 Anavyssos, Greece

The Mediterranean region is threatened by numerous geo-hazards that destroyed even entire communities in the historically recent past . However, in most Mediterranean regions, the geological processes that govern the occurrence, location, magnitude, recurrence and inter-relations among different geo-hazards are poorly known. To advance in their understanding is therefore of upmost scientific interest and societal relevance. We present the HADES project, starting in Fall 2011, that will undertake an interdisciplinary, basic-research investigation of the relationships among tectonics, magmatism, and sediment dynamics, and their influence on geo-hazards in the most tectonically active area of the Mediterranean Realm: the Aegean basin. The project aims at investigating geohazards by understanding an entire geological system: from the large-scale structure and physical properties of the subducting slab, mantle wedge, overriding lithosphere, and the seismic activity across the system to the crustalscale tectonics and sediment dynamics, including fault style and structure, long-term activity of fault systems, fault slip rates, marine paleo-seismology, and seismically-induced sediment dynamics. The project will integrate the data from several marine cruises and field campaigns that will take place during 2012, 2013 and 2014. During the project cruises we will acquire multichannel seismic reflection and wide-angle seismic data, sub-bottom profiler, multi-beam bathymetry, side-scan sonar data, and sediment coring. Further we will collect marine and land deep-penetrating electromagnetic data, and deploy a marine and land seismological network to obtain the multidisciplinary observations needed to study active geological processes and related geo-hazards. The project will provide a holistic understanding of how those phenomena, operating at different time and space scales, inter-relate to modulate geo-hazards in the region. The Aegean basin is the best suited area in the Mediterranean for such a study as is geodynamically very active, with active volcanism and has the highest seismicity. Here, geo-hazards occur at a comparatively higher rate, and conceivably can be studied in a relatively short-duration project. Within the Aegean we will survey a region that has active crustal faulting and volcanism, and has been struck by historically documented earthquakes and tsunamis. The largest earthquake in Greece in the past 100 years occurred in the study region, in a normal fault loosely identified offshore, and caused a regional 20-m-high tsunami wave.