Analyzing the Compensation Mechanism of Crete Island and Rhodos Basin (Eastern Mediterranean Sea) with Admittance Function

Abstract

It is a tectonically important concept how the crust and the upper mantle gravitationally balancing the topographic loads. Balancing the loads in a region can be determined by examining the topographic and gravity data. In this study, the balancing mechanism of Eastern Mediterranean region, which is quite tectonically complex, was determined by using Admittance function as the first time in the literature. In this context, Eastern Mediterranean region, which has different topographic/bathymetric, gravity values and tectonic features, was divided into two regions as Crete Island and Rhodos basin.  The effective elastic thickness values of these regions were obtained by using the coherency of admittance between gravity and topography values and average flexure depths of the crustal-mantle interfaces were calculated by forward-inverse solutions. As the result, it is determined that the isostatic models of Eastern Mediterranean regions do not fit with the Airy model and the effective elastic thickness values of Crete Island-its surroundings and Rhodos basin-its surroundings are approximately 6 km and 8 km, respectively. The average flexure depths of the crustal-mantle interfaces related to the optimal effective elastic thickness value of Crete Island and Rhodos basin are approximately 19-29 km and 20-32 km, respectively.

Keywords

• Eastern Mediterranean,Crete,Rhodos basin,effective elastic thickness,forward modelling,admittance analysis

Girit Adası ve Rodos Baseni’nin (Doğu Akdeniz) Dengeleme Mekanizmasının Girişim (Admittance) Fonksiyonu ile Araştırılması

Abstract

Kabuğun ve üst mantonun, topoğrafik yükleri  gravitasyonel olarak nasıl dengelediği tektonik açıdan önemli bir kavramdır. Bir bölgedeki yüklerin dengelenme durumu, o bölgeye ait topoğrafya ve gravite verilerinin irdelenmesi ile belirlenebilmektedir. Tektonik olarak oldukça karmaşık olan Doğu Akdeniz bölgesinin dengelenme mekanizması, girişim (Admittance) fonksiyonun kullanılmasıyla literatür genelinde ilk olarak bu çalışma kapsamında irdelenmiştir. Bu kapsamda, farklı topoğrafik/batimetrik, gravitasyonel değerlere ve tektonik özelliklere sahip Doğu Akdeniz bölgesi, Girit Adası ve Rodos baseni olmak üzere iki ayrı bölgeye ayrılarak incelenmiş, gravite ve topoğrafya verileri arasındaki girişim (admittance) uyumundan yararlanılarak bu bölgelerin efektif elastik kalınlık değerleri ve ayrıca düz-ters çözüm teknikleri ile kabuk-manto ara yüzeyine ait bükülme derinlikleri elde edilmiştir. Sonuç olarak, Doğu Akdeniz’de yer alan bu iki  bölgenin izostatik modellerinin Airy modeline uymadığı, Girit Adası ve çevresi için efektif elastik kalınlık değerinin ortalama 6 km olduğu, Rodos baseni ve çevresi için efektif elastik kalınlık değerinin ortalama 8 km olduğu saptanmıştır. En uygun efektif elastik kalınlık değerine karşılık gelen kabuk-manto ara yüzeylerine ait ortalama bükülme derinliklerinin Girit Adası ve çevresinde yaklaşık 19-29 km, Rodos Baseni ve çevresinde ise 20-32 km arasında değiştiği saptanmıştır. 

Keywords

• Doğu Akdeniz,Girit,Rodos baseni,Efektif Elastik kalınlık,Ters Çözüm,Girişim (Admittance) Fonksiyonu

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