Strong Motion Database for Crustal Earthquakes in Greece and Surrounding Area

Author(s): Scordilis, Emmanouel; Theodoulidis, Nikolaos; Kalogeras, Ioannis; Margaris, Basil; Klimis, Nikolaos; Skarlatoudis`, Andreas; Stewart, Jonathan P; Boore, David M; Seyhan, Emel; Savvaidis, Alexandros; Mylonakis, George; Pelekis, Panagiotis | Abstract: An updated Hellenic database of strong ground motion recordings together with the earthquake source properties and the site characterization of the recording stations are described here. The strong motion database consists of 2751 corrected recordings from 497earthquakes of focal depths hl45km and 338 recording stations, with source to site distances up to 300 km, covering the period from 1973-2015. The strong motion recordings were collected from Hellenic Strong Motion Networks operated by the Institute of Engineering Seismology and Earthquake Engineering (ITSAK), the Institute of Geodynamics, National Observatory of Athens (NOA-IG), as well as from the Civil Engineering Department, University of Patras (UPAN). All recordings were processed based on well-established routines and methodologies applied in worldwide strong motion databases such as the PEER, NGA-West2 database. The final database includes epicenter locations, focal depths, moment magnitudes (directly estimated or equivalently derived after a conversion procedure) for a significant number of earthquakes with Mg4.5and a number of finite fault plane solutions corresponding to earthquakes with Mg6.0. The data is compiled from existing catalogs published by Hellenic and international seismological centers. The properties for each recording station include surface geology, a measured or estimated time-averaged shear wave velocity in the upper 30m (VS30), and information on instrument housing. Out of the 338sites, 75 have in-situ shear wave velocity measurements while for the rest VS30 values are derived from proxy-based relationships based on terrain or geology combined with surface gradient.