Region-Time-Magnitude Analyses of the Seismicity in and around the Central Anatolian Region and Current Earthquake Potential

Abstract

The purpose of this study is to make detailed statistical analyses of earthquake occurrences in and around the Central Anatolian Region of Turkey and to forecast the possible earthquake regions in the future. In this scope, by performing the region-time-magnitude analyses of seismotectonic variables such as Mc-value, b-value, Dc-value, Z-value, the current/future earthquake potential was defined. b-value was computed as 1.26±0.07 by taking Mc=2.6 and this large value indicates that the earthquakes with small magnitude are dominant. Dc-value was calculated as 1.31±0.03 and this relatively small value shows that distance between the epicenters approaches the diameter of cluster, and earthquake activity is more clustered in larger regions/at smaller scales. Anomaly regions with low b-value and large Z-value at the beginning of 2019 were found in and around Tuz Gölü Fault Zone, Central Anatolian Fault Zone, Salanda and Niğde faults. As an important result, these regions may be considered as the most likely regions for strong/large earthquakes in the future.

Keywords

• Central Anatolia,b-value,Dc-value,Z-value,Earthquake potential

Orta Anadolu Bölgesi ve Civarındaki Depremselliğin Bölge-Zaman-Magnitüd Analizleri ve Güncel Deprem Potansiyeli

Abstract

Bu çalışmanın amacı, Türkiye’nin Orta Anadolu Bölgesi ve civarındaki deprem oluşumlarının detaylı istatistiksel analizlerini yapmak ve gelecekteki olası deprem bölgelerini tahmin etmektir. Bu kapsamda, Mc-değeri, b-değeri, Dc-değeri, Z-değeri gibi sismotektonik değişkenlerin bölge-zaman-magnitüd analizleri yapılarak, güncel/gelecek deprem potansiyeli ortaya konulmuştur. Mc=2.6 alınarak b=1.26±0.07 olarak hesaplanmıştır. Bu büyük değer küçük magnitüdlü depremlerin baskın olduğuna işaret etmektedir. Dc-değeri 1.31±0.03 olarak hesaplanmıştır ve bu nispeten küçük değer, episantrlar arasındaki uzaklığın kümelenme çapına yaklaştığını ve deprem aktivitesinin daha küçük ölçeklerde veya daha büyük alanlarda kümelendiğini göstermektedir. 2019 yılı başında düşük b-değerli ve yüksek Z-değerli anomali bölgeleri, Tuz Gölü Fay Zonu ve civarında, Orta Anadolu Fay Zonunda, Salanda ve Niğde faylarında gözlenmiştir. Önemli bir sonuç olarak, bu bölgeler gelecekteki büyük/güçlü depremler için en olası bölgeler olarak düşünülebilir.

Keywords

• Orta Anadolu,b-değeri,Dc-değeri,Z-değeri,Deprem potansiyeli

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