Comparative analysis of low-altitude magnetic survey sensitivity using unmanned aerial vehicles and land magnetic survey

The subject of the study is the problem of the decline degree of the information content of geophysical data when switching from land surveys to low-altitude geophysical survey using unmanned aerial vehicles. The research involves a comparative analysis of the information content of the unmanned aerial vehicle survey results and those of the land magnetic survey. The conducted research allowed to present the observed values of the magnetic field obtained  by both survey methods within the same area as well as the final information products in the form of the results of filtering and three-dimensional data inversion. It is shown that visual analysis of maps of the full vector of magnetic field strength gives the impression of a lower information content of magnetic survey performed by unmanned aerial vehicles. However, the data having been processed create final information products of identical information content. This concerns both the results of three-dimensional modeling of the effective magnetic susceptibility, and maps and plots of the anomalous magnetic field after filtering in a sliding window. The negative impact of geological interference from morainic deposits on ground data is also shown. Local magnetic anomalies based on unmanned aerial vehicle survey results can confidently correlate with land survey anomalies, whereas the data collected during low-altitude aeromagnetic survey using unmanned aerial vehicles have a lower error probability. The conclusions refer to a specific case and cannot be unambiguously applied  to any geological situation, however, the authors believe in the typicality of this example.

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