Güney ve Doğu Anadolu’ da Soğurulmanın (1/QC) Yanal Heterojenitesi

Bu çalışma coda kalite faktörü ile sismik aktivite, tektonik süreksizlik ve litosferik heterejonite arasındaki olası uyum ve uyumsuzluklarbelirlenmeye çalışılmıştır. Bu amaç ile farklı tektonik sistemler üzerinde bulunan ve sismik aktivitesi birebirinden farklı olan Kemaliye,Diyarbakır ve Erzurum sismik istasyonlarından elde edilen Sg dalgaları kullanılmıştır. Birbirinden farklı fay zonlarının etkisi altındakibu üç alanda sığ kabuğa ait yanal koda kalite faktörü (QC) ve soğrulma değerleri (1/QC) ile frekans bağımlılıkları (η) yanal değişimleribelirlenerek karşılaştırmalı olarak incelenmiştir. Çalışmada Qc ve η değerlerini elde etmek için izotropik tek saçılma yöntemikullanılmıştır. En düşük koda Q1=(82±5) değeri Kemaliye istasyonundan, en yüksek Q2=(90±5) değeri Diyarbakır istasyonundan veQ3=(86±3) değeri de Erzurum istasyonundan elde edilmiştir. En yüksek soğurma değerleri Kemaliye istasyonunda elde edilirken endüşük soğurma değerleri Erzurum istasyonundan elde edilmiştir. En yüksek η değerleri 0.96∓0.04 olarak Kemaliye sismik istasyonuverilerinden en düşük değeri 0.85±0.03 olarak Diyarbakır istasyonu kayıtlarından elde edilmiştir. Erzurum istasyonu için ise değeri0.88∓0.02 olarak elde edilmiştir. Koda değerleri 82 ve 90, frekans bağımlılığı değerleri 0.66 ve 1.27 aralığında elde edilmiştir. Üçbölgenin 1/QC ve frekans bağımlılığı değerleri, kabuğun sismotektonik aktivitesindeki bölgesel farklılıklara bağlı olarak 0.001-0.014arasında değişmektedir. Kemaliye bölgesine ait yanal soğrulma değerlerinin Erzurum ve Diyarbakır bölgelerinden oldukça farklıbulunmuş olması bu bölgenin tektonik olarak diğer iki bölgeden daha aktif olduğu gerçeği ile desteklenmiştir. Üç istasyona ait Koda vefrekans bağımlılığı değerleri ile bölgede bulunan üç farklı sismik rejim ve litosferik kabuk yapısına ait yeni bilgiler elde edilmiştir.

The Lateral Heterogeneity of Attenuation (1/QC) in Southeasternan Anatolia

In this study, possible adaptations and inadaptations between the coda quality factor and seismic activity, tectonic discontinuity and lithospheric heterogeneity were attempted to be determined. For this purpose, Sg waves obtained from Kemaliye, Diyarbakır and Erzurum seismic stations, which are on different tectonic systems and whose seismic activities are different from one another, have been used. In these three areas under the influence of different fault zones, the lateral code quality factor (QC) and attenuation values (1/QC) and frequency dependence (η) lateral chance of the shallow crust have been determined and analyzed comparatively. The single isotropic scattering method has been used to obtain Qc and η values in the study. The lowest coda value Q1=(82±5) was obtained from Kemaliye station, the highest value Q2=(90±5) was obtained from Diyarbakır station and Q3 = (86±3) value was obtained from Erzurum station. The highest attenuation values were obtained at Kemaliye station, while the lowest attenuation values were obtained at Erzurum station. The highest η values were obtained from Kemaliye seismic station data as 0.96∓0.04 and the lowest η value was obtained from Diyarbakır station records as 0.85±0.03. The value for Erzurum station η was obtained as 0.88∓0.02. Coda values were obtained in the range of 82 and 90 and frequency dependence values 0.66 and 1.27. The 1/QC and frequency dependence values of the three regions range from 0.001 to 0.014, showing regional differences in the seismotectonic activity of the crust. The fact that the lateral attenuation values of Kemaliye region were found to be quite different from the regions of Erzurum and Diyarbakir was supported by the fact that this region was tectonically more active than the other two regions. New information has been obtained for coda and frequency dependence values of the three stations and three different seismic regimes and lithospheric crustal structure in the region.

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