The new empirical magnitude conversion relations using an improved earthquake catalogue for Turkey and its near vicinity (1900–2012)

Abstract

Empirical magnitude conversion relationships are one of the important parameters for not only seismological studies but also seismic hazard analysis and development of the attenuation relationships. Particularly, for seismic hazard analysis, conversion of various types of magnitudes to moment magnitude, which is the most reliable and common magnitude scale, is a key requirement. Within this scope, different magnitude conversion equations have been derived by various researchers in the literature. In this study, new empirical magnitude conversion formulas for conversion from m b , M L , M d , and M S to M w were derived by using a recently established earthquake catalogue. The most important feature of the new relationships is the use of the maximum data with respect to the literature. It is a wellknown fact that having a greater number of data increases the sensitivity of the equations derived. Both orthogonal regression (OR) and ordinary least squares (OLS) were used to derive conversion equations, and the results obtained from these two methods were compared. In the derivation, 489 events with magnitudes in M w scale taken from the Harvard GCMT Catalogue were used. Residual graphs created for both methods showed that the OR method gives better results than OLS for conversion from M S to M w . On the other hand, the OLS method showed preferable performance for conversions from m b , M L , and M d to M w . The equations proposed in this study were also compared with other empirical relations in the literature.

Homogenized earthquake catalog and b-value mapping for Ethiopia and its adjoining regions

“…5(c) is again in good agreement with Scordilis (2006). On the other hand, the relationship proposed by (Akkar et al, 2010;Das and Sharma, 2011;Karimiparidari et al, 2013;Kadirioglu and Kartal, 2016) for both MW-mb and Ms. pairs has calculated slightly lower MW estimations when compared to the present study results and the estimations by Scordilis (2006) relation.…”

“…Similarly, the empirical magnitude conversion equations for Ms. vs Mw presented in this study (see equations (16, 17)) are compared with the previously developed magnitude conversion equations (8,9,10,11,12,14,15) respectively by different authors (Scordilis, 2006;Akkar et al, 2010;Das and Sharma, 2011;Karimiparidari et al, 2013;Kadirioglu and Kartal (2016). The comparisons are given in Fig.…”

“…However, relations proposed by Karimiparidari et al (2013) was used to develop conversion from M L to Mw by using equation (18,19). Relation proposed by Akkar et al (2010) (Scordilis, 2006;Akkar et al, 2010;Das and Sharma, 2011;Karimiparidari et al, 2013) (b) Result comparison MW versus M S of this study and obtained by (Scordilis, 2006;Akkar et al, 2010;Das and Sharma, 2011;Karimiparidari et al, 2013;Kadirioglu and Kartal, 2016) other hand which has relatively good R 2 and RMSE, were used for the conversion of M D to M W by using equations (23, 24).…”

Geomorphic evidence for active tectonic deformation in the coastal part of Eastern Black Sea, Eastern Pontides, Turkey

“…NAF: North Anatolian Fault, EAF; East Anatolian Fault, NEAF; Northeast Anatolian Fault, BSF; Borjomi-Kazbegi Fault, BKF; Black sea Fault. b) Inset map showing seismicity of Turkey and its vicinity(Kadirioğlu & Kartal, 2016).…”

A practical probabilistic earthquake hazard analysis tool: case study Marmara region

“…Historical events that occurred in the region are included in the catalogue using data from Ambraseys and Jackson (2000). A catalogue homogenisation was necessary to convert M s , M L and m b magnitude scales into moment magnitude, M w , and this was done using conversion equations specifically developed for Turkey by Kadirioğlu and Kartal (2016). After homogenisation, the data need to be declustered for the removal of dependent events (fore-and after-shocks).…”