Şevket DEMİRBAŞ, Seyit TOSUN, Tolga GÖNENÇA, Ayça YURDAKUL ÇIRMIKA, Oya PAMUKÇU

DOĞU ANADOLU BÖLGESİNDEKİ KABUK YAPISININ DÜŞEY VE YATAY YÖNLÜ ANALİZİ

Doğu Anadolu Bölgesi'nin tektonik rejimi Arap-Avrasya, kıta-kıta çarpışması ve buçarpışmanın mekanizması ile belirlenmektedir. Bu tektonizma ile oluşan Kuzey AnadoluFay Zonu (KAFZ), Doğu Anadolu Fay Zonu (DAFZ), Kuzey Doğu Anadolu Fayları, BitlisZagros Bindirme Zonu bölgenin litosfer yapısının karekterini yansıtmaktadır. Litosferyapısını irdelemek amacıyla bu çalışma kapsamında Doğu Anadolu Bölgesi'ne ait graviteanomalileri kullanılmıştır. Gravite verilerine önce 2. Trend Yöntemi uygulanarakanomalinin karakteri irdelenmiştir. Daha sonra aynı veriye, düşey ve yatay yönde türevyöntemleri uygulanmıştır. Genel olarak türev yöntemleri kullanılan çalışmalarda amaççalışma alanına ait yatay ve düşey yöndeki yapı sınırlarını saptamaktır. Böylece bu yöntem,çalışma alanındaki litosfer yapısının özellikleri ile ilgili fikir verir. Çalışma kapsamındaelde edilen türev sonuçlarına göre özellikle Bitlis Zagros Bindirme Zonu ile yapı geçişlerioldukça fazlalaşmaktadır. Son aşamada gravite çalışması ile bölgedeki güncel sismikaktivite birlikte değerlendirilmiştir. Sonuç olarak bölgede yapılmış önceki çalışmalar ilebirlikte bölgenin jeodinamik yapısı irdelenmiştir

VERTICAL AND HORIZANTAL ANALYSIS OF CRUSTAL STRUCTURE IN EASTERN ANATOLIA REGION

The tectonic regime of Eastern Anatolia is determined by Arabian-Eurasian continentcontinent convergence and the mechanism occurred with the convergence. NorthAnatolian Fault Zone (NAFZ), Eastern Anatolian Fault Zone (EAFZ), North EasternAnatolian Faults and Bitlis Zagros Suture Zone are formed by this convergence, representthe characteristic of lithospheric structure of the region. In the scope of this study, thegravity anomalies of Eastern Anatolia were used for investigating the lithosphericstructure. Firstly, second order trend analyses were applied to gravity data for examiningthe characteristic of the anomaly. Later, the vertical and horizontal derivatives methodswere applied to the same data. Generally, the purpose of the applying derivative methodsis determining the vertical and horizontal borders of the structure. Therefore, this methodgives the opinion about the characteristic of the lithospheric structure of the study region.According to the results of derivative methods, the structure transitions were increasedrather especially with Bitlis Zagros Suture Zone. At the last step, the gravity studies wereevaluated together with the seismic activity of the region. Consequently, the geodynamicalstructure of the region is examined with the previous studies done in the region.

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