Seismic quiescence and magnitude-frequency statistics of current earthquake activity in the Central Anatolian Region (Turkey) and its vicinity

Year 2019, , 645 - 652, 26.12.2019

Serkan Öztürk

https://doi.org/10.18586/msufbd.619968

Abstract

In this study, seismic
quiescence and magnitude-frequency statistics of current seismic activity in
and around the Central Anatolian Region of Turkey were achieved. Seismicity
studies in this region have gained considerable importance due to the
strong/large earthquake occurrences in recent years. b-value shows a tendency to decrease after 2002 and
decreases from 1.58±0.03 to 1.25±0.05 at the beginning of
2019. Region-time distribution of b-value shows significant changes in NF and its vicinity along the
south, west, northwest and southwest directions, among MFZ, KKFZ and KOFZ, in
and around SRF and along its northwest direction, between SRF and EAFZ. Seismic
quiescence regions at the beginning of 2019 consist the northwest ends of TGFZ and study area including AF, the northeast of SF, between
SF and CAFS, the northeast parts of CAFS, the west of MF, between SRF and EAFZ,
the southeast end of TGFZ, KKFZ and its vicinity, the southwest of Tuzgölü. Consequently,
these regions may be considered as one of the most likely areas for future
strong/large earthquakes.

Keywords

b-value, earthquake potential, seismic quiescence, seismic hazard

Orta Anadolu Bölgesi (Türkiye) ve civarındaki güncel deprem aktivitesinin sismik durgunluk ve magnitüd-deprem sayısı istatistiği

Abstract

Bu
çalışmada, Türkiye’nin Orta Anadolu Bölgesi ve civarındaki güncel deprem
aktivitesinin sismik durgunluk ve magnitüd-deprem sayısı istatistikleri
gerçekleştirilmiştir. Son yıllardaki güçlü/büyük
deprem oluşumları nedeniyle bu bölgedeki depremsellik çalışmaları oldukça önem
kazanmıştır. b-değeri 2002 yılından sonra bir azalma eğilimi göstermektedir ve 2019’un
başında 1.58±0.03’ten 1.25±0.05’e düşmüştür. b-değerinin bölge-zaman dağılımları, güney, batı, kuzeybatı ve
güneybatı yönleri boyunca NF ve civarında, MFZ, KKFZ ve KOFZ arasında,
kuzeybatı yönü boyunca SRF ve civarında, SRF ile DAFZ arasında önemli
değişimler göstermektedir. 2019 yılı başlangıcındaki sismik durgunluk
bölgeleri, TGFZ’nin kuzeybatı sonlarını ve AF’yi içeren çalışma alanını, SF’nin
kuzeydoğusunu, SF ile OAFS arasını, OAFS’nin kuzeydoğu kısımlarını, MF’nin
batısını, SRF ile DAFZ arasını, TGFZ’nin güneydoğu sonunu, KKFZ ve civarını,
Tuzgölü’nün güneybatısını içermektedir. Sonuç olarak, Bu bölgeler, gelecekteki
güçlü/büyük depremler için en olası alanlardan birisi olarak düşünülebilir.

Keywords

b-değeri, sismik tehlike, deprem potansiyeli, sismik durgunluk, sismik tehlike

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