Simulated Annealing Method: A Seismological Application for The Black Sea Basin

Yıl 2020, Cilt: 25 Sayı: 3, 95 - 106, 30.12.2020

Hamdi Alkan , Hakan Çınar

Öz

In this study, the current crust and upper mantle structure of the Black Sea Basin and its surroundings have been studied using data of broad-band earthquake stations. P-wave velocity, S-wave velocity, and Vp/Vs ratio (up to 300 km depth) were obtained for each station and they were associated with recent tectonic situation. To calculate the velocities, the P- and S-wave Receiver Functions were performed to the simultaneous inversion by the using Simulated Annealing method. The dataset included more than 400 teleseismic events. According to velocity histograms, while the Lithosphere-Asthenosphere boundary beneath the Eastern Black Sea Basin increased from north to south with a dome-like slope, a flat increase was observed in the Western Black Sea Basin in the same direction. Mean P-wave and S-wave velocities indicate the presence of the continental lithosphere around the Black Sea and its coastal area. According to these results, tectonically, it may be said that there is southward subduction beneath the Pontides.

Benzetilmiş Tavlama Yöntemi: Karadeniz Havzası için Bir Sismolojik Uygulama

Öz

Öz: Bu çalışmada Karadeniz Havza’nın ve civarının güncel kabuk ve üst manto yapısı çalışılmıştır. Bu amaç doğrultusunda, Karadeniz’in çevresinden seçilen geniş-bantlı deprem istasyonlarının telesismik kayıtları kullanılmıştır. Her bir istasyon altı için P-dalgası hızı, S-dalgası hızı ve Vp/Vs oranı (300 km derinliğe kadar) elde edilmiş ve güncel tektonik durum yorumlanmıştır. Hızların hesaplanması için P- ve S-dalgası Alıcı Fonksiyonları Benzetilmiş Tavlama yöntemi vasıtasıyla birleşik ters çözüm işlemine tabi tutulmuştur. Veri seti yaklaşık olarak 400 adet depremi kapsamaktadır. Elde edilen hız histogramlarına göre, Doğu Karadeniz Havzası’nda kuzeyden güneye doğru Litosfer-Astenosfer geçişi kubbe gibi bir eğim ile artmaktayken, Batı Karadeniz Havzası’nda ise aynı doğrultuda daha yassı bir artış gözlemlenmiştir. Ortalama P-dalgası ve S-dalgası hızları Karadeniz Havzası’nın çevresinde kıtasal özellikli bir litosferin varlığını işaret etmektedir. Tüm bu sonuçlara göre, tektonik olarak güneye eğimli bir yitimin var olduğu söylenebilir.

Anahtar Kelimeler

Karadeniz Havzası, Litosferik Yapı, Alıcı Fonksiyonları

Kaynakça

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