Rezidüel gravite alanı verilerinden 2 boyutlu doğrusal ve doğrusal olmayan ters çözüm modelini kullanarak bir tuz domunun simülasyonu

Gravite alan verilerinin ters çözümünde, genellikle belirsizlik problemleri ile ilgileniriz ve gerçekçiçözümler elde etmek için, ters çözüm algoritmasına derinlik ölçüm fonksiyonunu tanıtabiliriz. Buçalışmada, doğrusal ters çözüm yöntemi, gravite anomalisine neden olan bir kütlenin yer altındakiyoğunluk dağılımını tespit etmek amacıyla kullanılmıştır. Bu yöntemin geçerliliği ve doğruluğu,gürültüsüz ve gürültülü verileri kullanılarak, farklı modeller arasından iki sentetik gravite anomalisiüzerinde test edilmiştir. Ayrıca, çalışmada İran’ın kuzeybatısında yer alan bir tuz domundan eldeedilen 2 boyutlu gravite anomalisi de dönüştürülmüştür. Çalışma bölgesinde yer alan tuz domlarıpotas bakımından zengin kaynaklardır. Ters çözüm işlemi yapılan yapı üstten alta doğru ortalama 27metre ile 65 metre arasında bir derinliğe sahiptir. Aynı zamanda, karşılaştırma amacıyla bir doğrusalolmayan ters ölçüm modeli de kullanarak tuz domu simüle edilmiş ve çoğunlukla benzer sonuçlarelde edilmiştir.

Simulation of a salt dome using 2D linear and nonlinear inverse modeling of residual gravity field data

In gravity field inversion we usually dealing with underdetermined problems and for obtaining realistic solutions can introduce a depth-weighting function to the inversion algorithm. We employ a linear inversion method for determining the underground density distribution of the gravity causative mass. The validation and accuracy of method is tested on two synthetic gravity anomaly from different models, while the data are noise- free and corrupted with noise. In this paper, We also invert the 2D gravity anomaly produced by a salt dome from the northwest of Iran. The salt domes in the region under investigation are a rich source of Potash. The inverted structure demonstrate on average a depth to top and bottom of 27 m and 65 m, respectively. For comparison, we also have simulated the salt dome using the nonlinear inverse modeling. The results are mostly similar.

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