𝔖 Bobbio Scriptorium
✦   LIBER   ✦

An estimate of probabilistic seismic hazard for five cities in Greece by using the parametric-historic procedure

✍ Scribed by Päivi Mäntyniemi; Theodoros M. Tsapanos; Andrzej Kijko


Publisher
Elsevier Science
Year
2004
Tongue
English
Weight
987 KB
Volume
72
Category
Article
ISSN
0013-7952

No coin nor oath required. For personal study only.

✦ Synopsis


A probabilistic procedure was applied to assess seismic hazard for the sites of five Greek cities (Athens, Heraklion, Patras, Thessaloniki and Volos) using peak ground acceleration as the hazard parameter. The methodology allows the use of either historical or instrumental data, or a combination of both. It has been developed specifically for the estimation of seismic hazard at a given site and does not require any specification of seismic sources or/and seismic zones. A new relation for the attenuation of peak ground acceleration was employed for the shallow seismicity in Greece. The computations involved the area-and sitespecific parts. When assessing magnitude recurrence for the areas surrounding the five cities, the maximum magnitude, m max , was estimated using a recently derived equation. The site-specific results were expressed as probabilities that a given peak ground acceleration value will be exceeded at least once during a time interval of 1, 50 and 100 years at the sites of the cities. They were based on the maximum peak ground acceleration values computed by assuming the occurrence of the strongest possible earthquake (of magnitude m max ) at a very short distance from the site and using the mean value obtained with the help of the attenuation law. This gave 0.24 g for Athens, 0.53 g for Heraklion (shallow) and 0.39 g Heraklion (intermediate-depth seismicity), 0.30 g for Patras, 0.35 g for Thessaloniki and 0.30 g for Volos. In addition, the probabilities of exceedance of the estimated maximum peak ground acceleration values were calculated for the sites. The standard deviation of the new Greek attenuation law demonstrates the uncertainty and large variation of predicted peak ground acceleration values.