P ve S Alıcı Fonksiyonlarının Birleşik Ters Çözümü: Van Gölü Havzası Örneği

Yıl 2018, Cilt: 23 Sayı: 3, 231 - 242, 11.12.2018

Hamdi Alkan , Hakan Çınar

Öz

Bu çalışmada, Van Gölü Havzası’nda bulunan Kandilli Rasathanesi ve Deprem Araştırma Enstiüsü tarafından işletilen AKDM ve MLAZ geniş-bantlı deprem istasyonlarının verileri kullanılarak, P- ve S-Alıcı Fonksiyonlarının Birleşik Ters Çözümü’nden P- ve S-dalgası hız histogramları elde edilmiştir. Ps dönüşüm fazları derinlik-yığma sonuçlarında ve Sp dönüşüm fazları da yavaşlık-yığma sonuçlarında belirlenmiştir. Birleşik ters çözüm sonuçlarına göre, alt kabukta ortalama S dalgası hızları, P dalgası hızları ve Vp/Vs oranı sırasıyla ortalama 3.6 km/sn, 6.3 km/sn ve 1.80’ dir. Düşük hızlar, bölgedeki yaygın volkanizma ve Vp/Vs oranı ise mafik kayaçlar ile ilişkilendirilebilir. MLAZ istasyonu için elde edilen kabuk kalınlığı yaklaşık olarak 42 km iken (Vs 3.6 km/sn’ den 4.3 km/s’ ye ve Vp 6.3 km/sn’ den 7.9 km/s’ ye artmaktadır), AKDM istasyonu için elde edilen kabuk kalınlığı 39 km’ dir (Vs 3.7 km/sn’ den 4.1 km/s’ ye ve Vp 6.4 km/sn’ den 8.1 km/s’ ye artmaktadır). Üst mantoda ~90 km’ ye kadar S-dalgası hızı oldukça düşük olarak elde edilmiştir. Sonuç olarak, üst manto hızları sıcak, sığ astenosferik materyalden dolayı düşüktür.

Anahtar Kelimeler

Van Gölü Havzası, Kabuk ve Üst-Manto Yapısı, P ve S Dalgası Alıcı Fonksiyonları, Birleşik Ters Çözüm

Kaynakça

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