Edge enhancement of potential field data using the enhanced gradient (EG) filter

Year 2024, Volume: 174 Issue: 174, 55 - 66, 13.08.2024

Hazel Deniz Toktay Korimilli N Durga Prasad Ahmad Alvandi

https://doi.org/10.19111/bulletinofmre.1386653

Abstract

Potential field data play a critical role in interpreting various geologic structural features through edge detection filters that aid in mapping subsurface structural features. For this purpose, various filters have been introduced in recent years to determine lateral boundaries. However, each of these filters has its limitations and advantages. This study presents a new edge enhancement filter named “Enhanced Gradient (EG)” based on the Richards function and applies it to potential field data for structural mapping. The EG is tested on two dimensional (2D) and three dimensional (3D) synthetic magnetic models with sources buried at different depths and variable properties. The results from the EG filter provide more accurate and higher resolution horizontal boundaries and can avoid creating the false edges in the output results. In addition, the proposed filter was examined using aeromagnetic data from the Indiana region in the USA. The primary and secondary faults and geological formations are recognizable in the EG image. The results of the EG map will allow us to improve the qualitative interpretation of potential field anomalies in studying the structural and tectonic geology of the Indiana region in the USA.

Keywords

Edge Detection, Gradient, Potential Field, Mapping.

Thanks

The authors would like to thank the US Geological Survey (https://www.usgs.gov) for permission to use the geological information and the aeromagnetic data and Dr. Gordon Robert John Cooper for providing the Hilbert transform calculation scripts.

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