Comparison of frequency of occurrence of earthquakes with slip rates from long-term seismicity data: the cases of Gulf of Corinth, Sea of Marmara and Dead Sea Fault Zone

Abstract

In this article, through the comparison of knowledge relating to historical earthquakes with the understanding of present-day earthquake mechanics and overall GPS slip rates in the eastern Mediterranean region, it has been possible to obtain an idea of how frequently large earthquakes may be expected in some parts of the region. It has also been possible to make an assessment from these early events of slip rates over a long period of time for the Gulf of Corinth in Greece, the Marmara Sea in Turkey and the Dead Sea Fault System, as well as deriving long-term magnitude–frequency relations for these same regions. It has been demonstrated that slip rates calculated from historical data are in general comparable to those calculated from GPS measurements and field observations, while the size of historical earthquakes and their uncertainty can be quantified. This permits a more reliable estimation of the long-term hazard, the calculation of which is the concern of the engineering seismologist. It has also been shown that in most cases large earthquakes are less frequent when they are estimated from long-term data sets rather than from the instrumental period making the notion of recurrence time and of hazard assessment, questionable. This study focuses on some of the few areas in the world for which long-term macroseism information exists and which facilitate this kind of analysis.