Applications of a rapid sampling vehicleborne magnetometer

Abstract

A vehicleborne magnetometer enables high resolution magnetic surveying to be conducted with savings in time and labour. Established airborne systems are unsuitable for closely spaced traverses in high resolution mapping. To utilise the full sensitivity of currently available magnetometers on land it has been necessary to carry the instrument by hand and to record individually the data at discrete stations. Described is a method for simply overcoming the magnetic perturbation encountered in close proximity to a vehicle and thus enabling high fidelity analog or digital data to be recorded while driving over the ground. The unit is capable of a rapid rate of traversing, combined with the possibility of immediately investigating the geological significance of an observed anomaly. The technique lends itself ideally to "on site" data presentation providing "visual signal enhancement" of weak spatial anomalies hidden in temporal noise. Quantitative interpretation of the ground level profile may be automatically performed by applying a Hilbert Transform method and use of the "magnetic signature" of rocks is suggested for regional geological mapping.