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Edge detection is an important part of interpreting potential field geophysics data. It helps better recognition of magnetic anomaly features such as superficial position and shape. Many edge detection methods have been presented; however, due to the natural complexity of subsurface features, only a few of the processing techniques might be accurate. Because, in practical cases, multi-dimensional precision is essential, using other methodologies along with edge detection can be useful. As a new research, this study utilized the 3D inverse modeling procedure as a confirmation and completion tool for combining both subsurface magnetic susceptibility distribution and surface anomaly projection. This research focused on investigating simultaneous application of 3D inversion and edge-detecting methods that provide an accurate perspective view of sought sources with high magnetic susceptible properties. To perform the mentioned task, along with the definition of two new edge detection filters, some beneficial edge detection filters were implemented on synthetic data. Then, these filters were applied to the Charmaleh Iron deposit magnetic data to obtain a valid anomaly edge perimeter. Subsequently, a 3D inverse modeling scheme was run on the data to investigate the magnetic susceptibility properties of surface and underground structures. In order to validate our edge detection results and to achieve a proper interpretation, the utilized edge detectors and the inverted model results were overlaid, compared, and depicted concurrently. Drilling operations were also conducted within the jointly achieved favorable zones, which were in line with the research findings. Conclusively, it can be stated that joint consideration of the mentioned approaches can be advantageous attitude toward accurate interpretation of environments with highly magnetic anomalies. [ABSTRACT FROM AUTHOR]

One of the well-known geothermal potential areas in Iran is the Abgarm in Mahallat region. Due to existence of several hot springs, the Abgarm area is of particular importance in geothermal studies. To investigate the geothermal mechanism at Abgarm, geophysical surveys of magnetometry and magnetotelluric (MT) were utilized near hot springs to image the geometry of all geological requisites for trapping a geothermal reservoir. The ground magnetic data were inverted in 3D to construct a magnetic susceptibility model, where a deep intrusive igneous rock (as a heat source) and a shallow magmatic lava were inferred from the physical model. Euler depth estimation also provided insight to a shallow granodiorite unit embedded in a thick sequence of sediments. Dimensionality and strike analysis of the MT data were performed through the phase tensor method to investigate the general geometry of the sought reservoir for running a 2D TE + TM mode inversion scheme. Through 2D inversion of the MT data along three profiles across the favorable zones, the electrical resistivity models were used to image sedimentary units (i.e., cap rock, top soil, bedrock and reservoir) and magmatic rocks. Considering both geophysical properties led to illustrate a plausible geothermal reservoir in the area. [ABSTRACT FROM AUTHOR]