26 Kasım 2019, ML=6.3, Kuzey Durrës, Arnavutluk Depreminin Artçı Şok Dizisinin Davranışları Üzerine Bir Değerlendirme

Abstract

26 Kasım 2019, ML=6.3, kuzey Durrës, Arnavutluk depreminin artçı şok oluşumunun detaylı bir değerlendirmesi yapılmıştır. b-değeri 0.88 ±0.07 olarak hesaplanmıştır. b-değeri 1.0’e yakındır ve nispeten küçük b-değeri ML4.0 olan büyük artçı şokların fazla oluşundan kaynaklanmış olabilir. p-değeri, Mmin=3.1 ve Tstart=0.0034 gün alınarak 1.23±0.08 olarak hesaplanmıştır. Bu yüksek p-değeri artçı şok aktivitesinin nispeten hızlı azalım oranının bir sonucu olabilir. Dc-değeri 1.74±0.09 olarak hesaplanmıştır ve buda artçı şokların daha büyük ölçeklerde homojen olarak dağıldığı anlamına gelir. En küçük b-değerleri ve en büyük p-değerleri ana şokun kuzey, kuzeybatı ve kuzey kısımlarında gözlenmiştir. Daha düşük b-değerleri daha büyük gerilme değişişimler ile ilişkiliyken, daha büyük p-değerleri ana şoktan sonraki maksimum atım ile ilişkilidir. Sonuç olarak, artçı şok oluşumlarının bölge-zaman-magnitüd analizleri gerçek zamanlı artçı şok tehlikesinin hızlı değerlendirmeleri için önemli ipuçları sağlayabilir.

Keywords

• Arnavutluk
• Durrës depremi
• artçı şok
• b-değeri
• p-değeri
• Dc-değeri

An Evaluation on the Behaviors of Aftershock Sequence of November 26th, 2019 Earthquake, ML=6.3, North of Durrës, Albania

Abstract

A comprehensive assessment of aftershocks occurrence for the November 26th, 2019 earthquake, ML=6.3, 16 km north of Durrës, Albania was achieved. b-value was estimated as 0.88 ±0.07. b-value is close to 1.0 and relatively small b-value may be resulted from the plenty of larger aftershocks with ML4.0. p-value was calculated as 1.23±0.08 with Mmin=3.1 and Tstart=0.0034 days. This high p-value may be a result of the relative fast decay rate of aftershock activity. Dc-value was calculated as 1.74±0.09 and it means that aftershocks are homogeneously distributed at larger scales. The smallest b-values and the largest p-values were observed in the north, northwest and northeast parts of the mainshock. The smaller b-values correlate with the larger stress variations, whereas the larger p-values are related to the maximum slip after mainshock. Consequently, region-time-magnitude analyses of the aftershocks occurrence may supply important clues for the fast evaluations of real time aftershock hazard.

Keywords

• Albania
• Durrës earthquake
• aftershock
• b-value
• p-value
• Dc-value

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