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Gravite Anomalilerinden Gömülü Yapı Derinliğinin Belirlemesi için Bir Yaklaşım

Gravite anomalilerinden gömülü bir yapının derinliğini kestirmek için birçok yöntem geliştirilmiştir. Bu çalışmada, doğrusal bir bağıntı üretilerek normalleştirilmiş gravite değerlerinden yapı derinliğinin hesaplandığı bir yöntem tanıtılmıştır. Yöntem, gözlemlenen gravite verilerine uygulanabildiği gibi gravite anomali haritası üzerinde alınan profil verilerine de uygulanabilir. Özellikle, arazide ölçülen gravite verilerine kayan ortalama işleci uygulanması düzgünleştirilen verilerden küre, yatay ve düşey silindir gibi basit geometrik yapıların derinliklerinin kestirilmesinde yöntem oldukça yararlıdır. Bu yöntem, sadece kalıntılara değil, aynı zamanda kısa profil uzunluğundaki Bouguer gravite verilerine de kolaylıkla uygulanabilir. Bu çalışmada, gürültüsüz ve çeşitli oranlarda gürültülü kuramsal modellere uygulanmıştır. Gürültü başarı oranını düşürse de tatmin edici sonuçlar elde edilmiştir. Ayrıca, yöntemin geçerliliğini sınamak amacıyla, farklı araştırmacılar tarafından değerlendirilen Mobrun, Medford, Cuba ve Leona gibi dünyanın çeşitli alanlarında ölçülen gravite anomalilerinin literatürde yer alan değerlendirme sonuçları ile yöntem çözümleri karşılaştırılmıştır. Küre, yatay ve düşey silindir yapı modelleri için saptanan çözümlerin literatürde yer alan sonuçlarla uyumlu olduğu gözlenmiştir.

Anahtar Kelimeler:

Gravite, Kayan Ortalama, Küre, Yatay Silindir, Düşey Silindir

An Approach to Determine the Buried Structure Depth from Gravity Anomalies

Many methods have been developed to estimate the depth of a buried structure from gravity anomalies. The method introduced in this study is to calculate the depth of structure from normalized gravity values by generating a linear equation. The method can be applied to the observed gravity data as well as the profile data taken on the gravity anomaly map. In particular, the application of the moving average operator to the gravity data measured in the field is very useful in estimating the depths of simple geometric structures such as spheres, horizontal and vertical cylinders from the smoothed data. The method can be easily applied not only to residuals, but also to Bouguer gravity data with short profile lengths. In this study, the method was applied to noise-free data and noisy model data with varying degrees of noise ratio. In this study, it has been applied to the noise-free synthetic data and noisy data with varying degrees of noise rate. The results are satisfactory, although the added noise reduces the success rate. In addition, in order to test the validity of the method, the evaluation results of the gravity anomalies measured in various areas of the world such as Mobrun, Medford, Cuba and Leona, which were evaluated by different researchers, and the method solutions in the literature were compared. It has been determined that the solutions obtained for the sphere, horizontal and vertical cylinder structure models are compatible with the results in the literature.

Keywords:

Gravity, Moving Average, Sphere, Horizontal Cylinder, Vertical Cylinder,

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