A detailed seismic zonation model for shallow earthquakes in the broader Aegean area

Abstract

Abstract. In the present work we propose a new seismic zonation model of area type sources for the broader Aegean area, which can be readily used for seismic hazard assessment. The definition of this model is based not only on seismicity information but incorporates all available seismotectonic and neotectonic information for the study area, in an attempt to define zones which show not only a rather homogeneous seismicity release but also exhibit similar active faulting characteristics. For this reason, all available seismological information such as fault plane solutions and the corresponding kinematic axes have been incorporated in the analysis, as well as information about active tectonics, such as seismic and active faults. Moreover, various morphotectonic features (e.g. relief, coastline) were also considered. Finally, a revised seismic catalogue is employed and earthquake epicentres since historical times (550 BC-2008) are employed, in order to define areas of common seismotectonic characteristics, that could constitute a discrete seismic zone. A new revised model of 113 earthquake seismic zones of shallow earthquakes for the broader Aegean area is finally proposed. Using the proposed zonation model, a detailed study is performed for the catalogue completeness for the recent instrumental period.Using the defined completeness information, seismicity parameters (such as G-R values) for the 113 new seismic zones have been calculated, and their spatial distribution was also examined. The spatial variation of the obtained b values shows an excellent correlation with the geotectonic setting in the area, in good agreement with previous studies. Moreover, a quantitative estimation of seismicity is performed in terms of the mean return period, T m , of large (M ≥ 6.0) earthquakes, as well as the most frequent maximum magnitude, M t , for a typical time period (T = 50 yr), revealing significant spatial variations of seismicity levels within the study area. The new proposed seismic zonation model and its parameters can be readily employed for seismic hazard assessment for the broader Aegean area.

Seismic hazard for the Trans Adriatic Pipeline (TAP). Part 1: probabilistic seismic hazard analysis along the pipeline

“…The seismogenic model proposed for the TAP route (400-km wide from the TAP route itself) is, then, based on all available geological literature (Aliaj 1998(Aliaj , 1999(Aliaj , 2000Velaj et al 1999;Robertson and Shallo 2000;Nieuwland et al 2001;Zelilidis et al;Roure et al 2004;Frasheri et al 2009;Lacombe et al 2009;Vilasi et al 2009;Silo et al 2010;Jardin et al 2011;Jouanne et al 2012), on earthquakes distribution (Fig. 5), and previous proposed seismogenic zonation for Albania (Aliaj et al 2000(Aliaj et al , 2004Aliaj 2002;Sulstarova and Aliaj 2001), for Greece (Papaioannou and Papazachos 2000;SEAHELLARC Working Group 2010, 2014Vamvakaris et al 2016), for Bulgaria (Orozova-Stanishkova and Slejko 1994; Simeonova et al 2006), for North Macedonia (Salic et al 2010), and Italy (Meletti et al 2008).…”

“…The seismogenic model for broader Greece (Pavlides et al 2010;Caputo et al 2012;Vamvakaris et al 2016) has been fully adopted with very minor changes along its peripheral margins to take into proper consideration also the national seismogenic models proposed for Bulgaria (Simeonova et al 2006). In particular, as these areas are quite far from the TAP route and can contribute very marginally to the expected ground motion, fewer details have been incorporated to allow a conservative distribution of the seismicity.…”

Recent seismic activity at Cephalonia (Greece): a study through candidate electromagnetic precursors in terms of non-linear dynamics

“…Following the detailed study presented in Vamvakaris et al (2016), we incorporated the seismic zones proposed there for our area of study. Thus, as presented in Fig.…”

“…Thus, as presented in Fig. 8, we defined five separate seismic zones, based on the criteria explored in Vamvakaris et al (2016) and the seismic zonation proposed by them. Since the study area comprises the most seismically active zone in Greece, assigned also the highest value in the Earthquake Building Code for the country, a large number of source, stress, and strain studies have been used in their study to establish such a definition of zoning.…”

The Seismological Network of Aristotle University of Thessaloniki, Greece (AUTHnet)

“…Thus, the completeness magnitude for the broader Thessaloniki area is M c =2.9 since 1981 and M c =2.4 since 1990 (Vamvakaris et al, 2016). Recently, the completeness in this area is further improved with M c =2.0, while for the rest of the network area the completeness magnitude increases to 2.5 or more, especially close to the network boundaries ( Figure 6.6).…”