The Gokceada Island (Northwest of Turkey) Earthquake of Mw 6.5 on 24 May 2014: Strong-Motion Examinations

Yıl 2018, Cilt: 20 Sayı: 60, 982 - 999, 15.09.2018

Elçin Gök

Öz

This
paper aims to study the Gokceada Island earthquake from an engineering
seismological point of view. On May 24, 2014, a large earthquake of magnitude
6.5 occurred in the Northwest of Turkey. The highest recorded peak ground
acceleration is at Gokceada Island station. The evaluation of site
amplification effects has been carried out, using the data from the main shock
and aftershocks of the earthquake. For each site, the standard spectral ratio
(SSR) and horizontal to vertical spectral ratio (H/V) methods were calculated
for 29 strong motion stations. The results show a clear influence of the site
soil conditions on the amplification of ground motion. Furthermore, the peak
ground acceleration (PGA) study was performed using attenuation relationships
at 53 location sites to find out how they were affected by the ground motion.
The highest PGA value was found near the epicenter, and it's attenuated with
distance. We used some ground motion prediction equations to compare observed
PGA values at stations with them. The measured values were significantly higher than the
prediction models.

Anahtar Kelimeler

Site effect, amplification, Gokceada Island earthquake, accelerometer

24 Mayıs 2014, Mw 6.5 Gökçeada (Kuzeybatı Türkiye) Depremi: Kuvvetli Yer Hareketi Çalışmaları

Öz

Bu
çalışma, Gökçeada depremini mühendislik sismolojisi açısından incelemeyi
amaçlamaktadır. 24 Mayıs 2014' de, Türkiye’nin kuzeybatısında 6.5 büyüklüğünde
bir deprem meydana geldi. En yüksek yer ivmesi, Gökçeada istasyonunda
kaydedilmiştir. Zemin büyütme etkilerinin değerlendirilmesi için depremin ana
şok ve artçı sarsıntılarından elde edilen veriler kullanılmıştır. Depremi
kaydeden 29 adet ivme-ölçer istasyonunda standart spektral oran ve yatay-düşey
spektral oran yöntemleri kullanılarak hesaplama yapılmıştır. Sonuçlar, yer
hareketinin zeminler üzerindeki net bir etkisini göstermektedir. Ayrıca depremi
kaydeden 53 yerleşim yerindeki en büyük yer ivmesi değerleri azalım ilişkileri
kullanılarak incelenmiştir. En büyük yer ivme değeri merkez üssün yakınında bulunmuş
ve mesafeye bağlı olarak azaldığı gözlenmiştir. Bazı yer hareketi tahmin
modelleri kullanarak, ölçülen değerlerle modelleri karşılaştırdığımızda
istasyonlarda ölçülen değerler tahmin modellerinden oldukça yüksek çıkmıştır.

Anahtar Kelimeler

Zemin etkisi, büyütme, Gökçeada depremi, ivme-ölçer

Kaynakça

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