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

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

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

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.

Keywords:

Site effect, amplification, Gokceada Island earthquake, accelerometer,

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