Investigation of the seismic damage caused to the Gunung Sitoli (Tögi-Ndrawa) cave by the 2005 Great Nias earthquake

Öz

Anahtar Kelimeler

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2005 Büyük Nias depreminin Gunung Sitoli (Tögi-Ndrawa) mağarasında neden olduğu sarsıntı hasarının incelenmesi

Öz

Aletsel dönem öncesi bölgelerin depremselliğinin niceliksel olarak değerlendirilmesi oldukça önemlidir. Son yıllarda karstik mağaralardaki sarkıt ve dikitlerde oluşan hasarlar, aletsel dönem öncesi depremselliğindeğerlendirilmesinde kullanılmaktadır. 2005 yılında meydana gelen Büyük Nias depreminde hasar gören NiasAdası karstik mağaradaki 2007 yılının Temmuz ayında incelenmiştir. Bu makalede önce 2005 Nias Adası’ndadepreminin sismo-tektonik ve kuvvetli yer hareket özellikleri kısaca sunulmuştur. Daha sonra Nias adasındaGunung Sitoli veya Tögi Ndrawa olarak adlandırılan karstik mağaradaki sarkıt ve dikitlerde meydana gelmiş hasarlar sunulmuş ve 2005 Nias adası depremi ile daha önceki depremler arasındaki ilişkiler tartışılmıştır. Buçalışmadan elde edilen en önemli sonuçlardan biri, hiç kuşkusuz, karstik mağaralardaki hasarların geçmiştekidepremlerin belirlenmesinde oldukça kullanılabilir olmasıdır. Bunun yanı sıra, yeraltı kaya yapısı olarak, karstikmağaranın duraylılığı görgül ve analitik yöntemlerle değerlendirilmiştir. Sarkıt ve dikitlerin deprem sırasındakihasar görme olasılığını incelemek üzere sismik katsayı yaklaşımına dayanan bir yöntem önerilmiş ve yapılandeğerlendirmeler tartışılmıştır

Anahtar Kelimeler

• Nias depremi, sarsıntı hasarı, sarkıt, Tögi Ndrawa mağarası

Kaynakça

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