TRANSFORMATION OF GEOMAGNETIC DATA STUDY BY USING 3D EQUIVALENT SOURCE METHOD

• Main Author: Belia, Samuel
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/43984
• Institution: Institut Teknologi Bandung

Interpretation of potential field data – especially geomagnetic data – can be tricky, by the complex nature of magnetic sources. Approach using several methods is needed to support geomagnetic data interpretation. In this thesis, reduction to the pole transformation was employed to relocate extreme magnetic anomalies to be over their sources. Along with reduction to the pole, upward continuation transformation was also employed to provide insights regarding shallow and deep magnetic sources, as well as to combine or to compare individual surveys at certain constant elevation. Additionally, a program was devised by the author to perform the transformations by using 3D equivalent source method, which utilizes the inherent ambiguity in potential field modelling. The equivalent source acquired from inverse calculation may not be geologically proper, however the resulting data resembles the real data, and can act as a gateway towards potential field data transformations. The result of this research using synthetic model and field data showed that reduction to the pole transformation could simplify the determinination of magnetic anomaly source’s location, and upward continuation transformation could aid data interpretation in a more regional way. The outcome of upward continuation transformation from reduced to the pole Karangsambung geomagnetic data showed the association of the high magnetic anomaly with diabase intrusion in the observation area. Overall, geomagnetic data transformation using equivalent source technique is functional in terms of utility and effective for uneven surface