Grid araştırma yöntemi ile yerel ve bölgesel depremlerin konumlarının belirlenmesi

Öz

Bu çalışmada deprem konumu belirleme probleminin çözümünde “Grid Arama” yönteminin kullanılması ve yöntemin değişik durumlardaki etkinliği incelenmiştir. Bu amaçla ağ geometrisinin çözüm üzerindeki etkisini araştırmak için farklı istasyon dağılım geometrisine sahip üç ayrı yapay istasyon ağı seçilmiştir. Ayrıca tüm istasyon ağları için depremin; istasyon ağının içinde, hemen dışında ve daha da uzağında olma durumları göz önüne alınmaktadır. Bunun yanı sıra, ortam hızının yanlış seçilmesi, oluş zamanının yanlış belirlenmesi ve hata içeren veri olması durumlarında yöntemin etkinliği incelenmiştir. Yöntem, sadece Pg ve Sg dalga fazları okumaları içeren 54 adet, Karadeniz’de deniz içinde meydana gelmiş ve sismolojik merkezlerince çözümü yapılmış 54 adet gerçek deprem verisi üzerinde uygulanarak depremlerin yeniden konumları belirlenmiş ve diğer sonuçlarla mukayese edilmiştir. Bu çalışma ile elde edilen sonuçlara göre, çözümlenen birçok depremin hiposantır konumu klasik yöntemle elde edilen konumlara oldukça yakın olduğu bulunmuştur.

Anahtar Kelimeler

• Grid arama yöntemi
• Hiposantır
• Episantır
• Deprem konumu belirleme
• Doğu Karadeniz depremleri

Determination of locations of local and regional earthquakes by grid search methods

Abstract

In this study, “Grid Search method” has been examined for both its efficiency and capability in solving earthquake location problems even if various situations. For this reason, three simulated (or artificial) seismic networks that pose different station geometries have been investigated effects of the network geometry on the solution. Three cases in which earthquakes occurred in, near, and far from the networks have been also considered in this study. In addition, the effectiveness of the method has been examined in cases where the seismic velocity is incorrect, origin time is misdetermined and data is contained errors. The method has been applied on 54 real earthquakes, which both Pg and Sg phase readings are available, that occurred near the coast of the Eastern Black Sea and have been previously located by the Seismological Centers and obtained results have been compared with the previous results. It has been found that the most earthquake hypocenters determined by this method were close to the locations determined by the classic methods.

Keywords

• Grid search method
• Hyposantr
• Epicenter
• Earthquake Location problem
• Eastern black sea Earthquakes

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