Estimating The Location of a Buried Body from Magnetic Anomaly Through Normalized Full Gradient: A Case Study from The Sapinuwa Ancient City, Turkey

Abstract

In geophysics, whether the structure is close to the surface or deeper, information about the depth and location of the structure can be obtained by using magnetic data. The importance of this study is an example of the application of the Normalized Full Gradient (NFG) method to an archaeological site to find the depth and location of structures that cause magnetic anomalies collected at the archaeological site. One of the parameters affecting the shape and size of the magnetic anomaly is the depth of the source causing the anomaly. For this reason, it is significant to determine the location of the source correctly. One of the methods used to determine the depth of structure using magnetic field data is NFG technique. In the application of downward analytical continuation, distortions due to the passage of mass depth occur and this method invalidates this. The NFG technique was tested on anomalies caused by prism-shaped synthetic models. Test studies on synthetic models with the NFG technique have yielded satisfactory findings. Based on the findings, the NFG technique was carried out to the real magnetic anomaly collected in the ancient city of Sapinuwa. The findings were compared with the building remains unearthed as a result of the proposed trench excavations. The obtained results have shown satisfactory results.

Keywords

• Geophysics
• Normalized Full Gradient
• NFG
• Magnetic anomaly
• Sapinuwa ancient city

Thanks

This study is part of the PhD thesis named “Potansiyel alanlarda Otomatik Değerlendirme Teknikleri ve Arkeolojik Alanlara Uygulanması, (2003)” of Şenol Özyalın. I would like to thank Prof. Dr. Aygül Süel and Dr. Mustafa R. Süel, who directed the excavation of the ancient city of Sapinuwa for providing valuable support during the collection of magnetic data.

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