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Novel methods for near-surface hydrogeological feature enhancement from high-resolution airborne magnetic data

Created 17/10/2025

Updated 17/10/2025

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The delineation of near-surface (0-300 m) hydrostratigraphy and tectonic features is essential for successful characterisation of groundwater systems and subsequent hydrogeological modelling. While most remote sensing of such systems is commonly achieved using high-resolution airborne electromagnetic (AEM) data, validated by drilling data, and complemented by the use of terrain and multispectral data, and borehole and ground hydrogeophysics, it is shown that there is also a useful role for high-resolution magnetic survey data. Various filtering of gridded magnetic data, when image-enhanced and interrogated with other datasets, reveal features such as faults, dykes and other structures which may influence the distribution and movement of groundwater. One of the most useful enhancements of magnetic data is the tilt angle, which is derived from the arc tangent of ratio of the vertical and horizontal derivatives of the reduced to the pole magnetic data. As the tilt amplitudes are always between ±90° regardless of the magnetic derivative amplitudes, this processing method acts similarly to automatic gain control to highlight both strong and weak source responses. A useful application of this tilt angle is estimating relative depths of magnetic features. Additional data, if available, can be used to calibrate these depth estimates. Dip directions of source contacts can be estimated by using the attitudes of multiscale edges, derived from the maxima of total horizontal derivative data. Examples of the utility of high-resolution magnetic data, in its complementary role, are presented for two groundwater assessment project areas — the Menindee Lakes region in western NSW and the Keep River catchment in the Northern Territory. Presented at the 2018 Australasian Exploration Geoscience Conference

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Field Value
Title Novel methods for near-surface hydrogeological feature enhancement from high-resolution airborne magnetic data
Language English
Licence Not Specified
Landing Page https://data.gov.au/data/dataset/9d2d6002-64e6-4e19-81ba-197972c54142
Contact Point
Geoscience Australia Data
clientservices@ga.gov.au
Reference Period
Geospatial Coverage
Map data © OpenStreetMap contributors
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Data Portal Geoscience Australia

Data Source

This dataset was originally found on Geoscience Australia "Novel methods for near-surface hydrogeological feature enhancement from high-resolution airborne magnetic data". Please visit the source to access the original metadata of the dataset:
https://ecat.ga.gov.au/geonetwork/srv/eng/csw/dataset/novel-methods-for-near-surface-hydrogeological-feature-enhancement-from-high-resolution-airborn