Document Type : Original Research Paper

Authors

1 Institute of Geophysics, University of Tehran, Tehran, Iran

2 School of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran

Abstract

The Shavaz iron deposit, located in the southwest Yazd province in Central Iranian Block, near The Bafq metallogenic belt, is a significant and economically valuable iron oxide-apatite resource. It features hematite and a minor content of magnetite, detectable through potential field geophysical surveys. This study aimed to target magnetite mineralization within the deposit using constrained susceptibility inversion. We began by simulating a multi-source synthetic model with three identical cubes at different depths to evaluate the sparse norm inversion approach. The method was then applied to the case study after the essential magnetic data corrections. To refine the interpretation of residual magnetic anomalies and gain insights into their source and depth, the analytic signal and upward continuation methods were employed. Inversion results across different cross-sections revealed two distinct, shallow, lens-shaped magnetite mineralizations with an average vertical extent of 60 meters. Notably, one magnetite body lies approximately 30 meters deeper due to the Dehshir-Baft fault influence. Low normalized mis-fit values confirmed the successful minimization of the objective function during inversion. Additionally, the reconstructed susceptibility models align well with the previous geological studies and borehole data, demonstrating the efficiency of the sparse norm inversion algorithm.

Keywords

Main Subjects

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