Source Location and Depth Estimation Using Normalized Full Gradient of Magnetic Anomalies

Year 2012, Volume: 33 Issue: 2, 141 - 168, 01.03.2012

Bülent Oruç

Abstract

Keywords

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Manyetik Anomalilerin Normalize Tam Gradyenti İle Kaynak Lokasyon Ve Derinlik Kestirimi

Abstract

Normalize tam gradient (NTG) yöntemi potansiyel alanların tekil noktalarının belirlenmesi için uygulanan yöntemlerden biridir. NTG yöntemi, ölçüm seviyesinin altındaki aşağı uzanım seviyelerinde veri süzgeçlemesi ve dönüşümüne dayalı bir yöntemdir. Yöntem manyetik anomali kaynaklarının yatay lokasyon ve derinliğinin belirlenmesinde kullanılmıştır. Yöntemin uygulanabilirliği, yatay silindir ve düşey dayk gibi iki boyutlu teorik modeller üzerinde test edilmiştir. NTG alanının maksimumları kaynak kütlelerin yatay lokasyonlarını ve derinliklerini vermektedir. NTG yöntemi manyetik arama yöntemi için önemli bir problem olan derinlik kestiriminde iyi sonuçlar sunmaktadır.NTG yöntemi manyetik anomalilerin dönüşümünde ve süzgeçlenmesinde, esas olarak Fourier serilerinin katsayılarının hesaplanmasına dayanır. Katsayıların üst harmonik sınırı, Fourier kosinüs katsayılarının logaritmik spektrumunun zarfı üzerindeki kırılma noktasından belirlenebilir. Ayrıca bu çalışmada, aşağı uzanım işlemi sırasında ortaya çıkan yüksek frekanslı gürültüyü yok etmek için kullanılan yuvarlatma faktörünün belirlenmesinde basit bir işlem de sunulmaktadır. NTG yöntemi Güney İllinois’deki (ABD) manyetik veriye uygulanmıştır. NTG yöntemiyle elde edilen sonuçlar, diğer yöntemlerle bulunan sonuçlarla uyumludur

Keywords

Manyetik anomaliler, anomali kaynakları, normalize tam gradyent

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