Fluxgate three-component magnetometers for cost-effective ground, UAV and airborne magnetic surveys for industrial and academic geoscience applications and comparison with current industrial standards through case studies

Abstract

In applied geophysics, magnetic methods are used in a wide range of industrial and academic applications with environmental, engineering or exploration components (e.g. military ordnance detection, pipe detection, archaeology, resources exploration, geological mapping). According to the type of application and the scale of the study, surveys can be conducted on the ground or airborne, each having its own industrial standard. In ground survey applications single component or scalar gradiometers are widely used. In airborne surveys the intensity of the magnetic field is measured with scalar magnetometers and the disturbances of the aircraft are compensated with real-time compensation units.This paper proposes another approach using the latest developments on the use of fluxgate three-component magnetometers. They have a light weight, a low power consumption, are rugged and allow a simple magnetic compensation of the carrier. They can provide a more precise and/or a more cost effective alternative to current measuring standards. They can also be mounted on UAVs to fill the gap in measurement capabilities between ground and airborne surveys, and therefore offer a new range of applications. A review of four case studies concerning archaeology, unexploded ordnance detection, lithology and structural geology studies is presented to illustrate the possibilities of application of such an approach and how it compares to current industrial standards in ground and airborne surveys.