AEGC : Brisbane 2023 Workshop



March 14th, 2023

Registration Deadline

January 31st, 2023


Des FitzGerald, Jeff Thurston, Mike Morse, Rainer Wackerle, Seda Celebier, Rod Paterson, Clive Foss, Ed Beigert

Back to The New Basics



The workshop aims to update upon the quarter-century-old comprehensive treatment and surveying practices of magnetic surveys as outlined in the ASGO Journal ‘Airborne Magnetics and Radiometrics Surveys, Volume 17, Number 2 1997’. The workshop will guide participants through the process of not only extracting depth data, but geological features and physical properties. Suvery practices has evolved substantially, and we comment on the Australian Magnetic Survey legacy by state.



Uplifting Survey Data – The good, bad and the ugly of data
Rainer Wackerle and Mike Morse

After 25 years, and 5 major compilation efforts, the Australian continental scale magnetic grid is being audited for the quality of the underlying key 250K survey line data. Initially the aim of the continental grids was to get coverage, accepting good, bad and indifferent surveys; which formed the first edition magnetic map of Australia, but this was quickly shown to have issues. The reality now is that uniform quality is now required and expected as inputs to, and as result from the the continental magnetic grids, given it’s pivotal role in exploration. A start has been made on checking all the surveys which have been archived and processed over the years. Our demonstration will cover the concerns for the range of errors in the magnetics and radiometric data, as well as the complexities and costs of auditing such work. To provide an example, almost all of the NT data acquisition projects have data structure and/or navigation problems, which are addressed to produce a preliminary NT dataset with the following properties:

Consists of individual surveys.

Lines and tie lines in the same database.

Plots in their correct position in the Northern Territory.

Each survey consisting of a set of unique line numbers.

Each line having a monotonically increasing fiducial number sequence.

A second phase of this work is on-going, and examples and reports of progress will be discussed for Victoria and NSW. And in the age of machine-learning, we will discuss how better quality metadata is derived.

Feature Extraction – Cauchy Derivatives and stable downwards continuation.
Des Fitzgerald and Jeff Thurston

We will outline how fundamentally improved algorithims and more complex workflows, that honor the underlying physics, continue to evolve.

Magnetic Transects – An application to basalt flood plains, to find depths and thicknesses of more than one flood event.

Euler Deconvolution Improvements – stabilizing the solutions for signal hot-spots by using Hilbert transforms.

Multi-Scale edge Detection (WormE) – improved extraction of contacts and dips for large scale features with an application to the Darling Fault

Dyke recognition – application in the Broken Hill district

Cauchy Derivatives by Integration – providing higher order derivatives of potential fields, using 100 year old theory. Application in both 1D/2D line and gridded data.

Automation -All techniques will be shown using a desktop interface, and all capabilities will be mirrored via the Protobuf messaging + Python scripting. A jump into 3D context will be discussed throughout.


Hard rock and soft rock, exploration strategies.
Seda Celebier

A discussion in the advancements, tip and tricks for deriving a candidate 3D Model from 2D geology maps. Case Studies for the Mansfield Syncline (with addition of Magnetic Data), Brockman Syncline and Platreef platinum style deposits are used for illustration.

Stochastic modelling and inversion using magnetics and geological constraints.
Rod Paterson

We will review the magnetic inversion specifically using the stochastic inversion method with or without geological constraints and how this can assist in drillhole targeting. We show how geological constraints can be derived using some of the magnetic methods being discussed in this workshop. This information is used to build a geological starting model. We demonstrate how this can help constrain the stochastic inversion and how the derived model uncertainty can be used to design and optimise future drilling campaigns. A case study with a focus on IOCG and Cu/Ni/PGEs.

Analysis and inversion of magnetic field data with expression of remanent magnetization .
Clive Foss

This session with start with advice as to how recognize remanence contributions and make preliminary estimates of magnetization direction from visual inspection of magnetic fields both across Australia and globally. We will then review the application of magnetic field transforms to variously enhance or mitigate the expression of remanent magnetization in magnetic field data and systematically evaluate the capability and limitations of recovering magnetisation direction estimates from magnetic field inversion. Through the workshop we will investigate 12 different magnetic field anomalies due substantially to remanent magnetisation. Finally, we will look at the Australian remanent anomaly database – a freely available web based utility highlighting magnetic anomalies across Australia due to remanent magnetisation and providing a download of inversion models and results.

Kill or Drill – Magnetic Technologies and Attractive Decisions
Ed Biegert

In this workshop you have learned about advances in tools, techniques, inversion capabilities, and data resources enabling better integration of magnetic data with geology and other geophysical data to enhance your exploration and optimise drilling campaigns for improved economic performance.

After a brief review and summary, you will step into the role of Decision Executive and use your newly acquired skills to make early “kill or drill” decisions in a fast-paced game of skill and chance. You will discover how magnetic technologies and improved techniques can steer exploration and exploitation decisions in several examples and case histories.

What are the learning outcomes?

You will become updated on Magnetic methods for exploration, which have had many significant improvements. Learn how cutting the usual corners is no longer necessary due to improving computation capabilities. There will be a discussion about better uplifting and higher quality requirements for survey data and how signal processing is propelled towards embracing more appropriate physics for potential fields, away from previous simple approximations.

The practical workshop will show real case studies and forward models to demonstrate the extraction of geological sections from standard airborne magnetic datasets.

Workshop Details

14th March, 2023
Location and Venue to be confirmed by AEGC
For Registration and Fees see AEGC


Includes 30-day-software licenses to latest versions of Intrepid and GeoModeller, training manuals and example datasets.
Note that this is intended as a “A Bring Your Own Laptop Workshop”. For any installation queries or requirements please contact our support.


Who should attend the workshop

People who use magnetic survey data for green field exploration mapping and brownfield mapping around producing mines.


Your Instructors

Des Fitgerald

Des has over 30 years’ experience with Intrepid Geophysics as owner, pioneer and now, Chief Scientific Officer. His major projects have included:

The development of the Intrepid software, for geophysical processing, with Geoscience Australia (GA)

A complete compilation of the Australian regional geophysical maps (both on-shore and off) for magnetics, gravity and bathymetry in partnership with Geoscience Australia.

The liaising with the French Geological Survey to further develop and promote new technology for 3D Geological mapping, known as GeoModeller, with potential field geophysics.

Des holds a PhD in Mining Engineering from the University of Melbourne. And has been an influential members across a number of groups such as Spatial Vision, RMIT Innovation Ltd, and GeoJAG.

Ed Biegert

Creative Problem Solver | Thought Leader | Stratergist Enabling cost-effective oil and gas exploration. He sits on the Rice University Science Masters’ Program board of Affiliates, is a founding member of Industry-Rice Earth Science Symposium initiative, was a director for the Alliance for Marine Remote Sensing, and was a director of the Geosat Committee, Inc. He has broad interest in the physics, environmental and Earth sciences and has made contributions in medical physics

Rod Paterson
Rod is a multi-skilled geoscientist with 30 years’ experience in mining and the exploration for tin, base metals, gold and heavy mineral sands. He holds a B.Sc in Geology and Geophysics and has proven analytical abilities in the fields of geology, geochemistry, geophysics and remote sensing and a successful track record in ore resource/reserve estimation across a wide range of commodities.
Rod has demonstrated skills in the integration of multidisciplinary data in geographic information systems or image processing environments as well as the processing of ground and airborne electromagnetic, magnetic, radiometric and other remotely sensed data. He also has many years of experience in software design and development with a strong focus on robust and user-friendly interfaces. Rod is a highly motivated self-starter with excellent long term vision in exploration research and product deliverance.
Jeff Thurston

Jeffery B. Thurston received his BS (1998) from the University of Alberta in physics and an MS (1991) in geophysics. He worked at Home Oil Co. Ltd., the LITHOPROBE Seismic Processing Facility, and Commonwealth Geophysical Development Co., Ltd., before joining Geoterrex in 1994. His interests include algorithm development and applications for mapping with geophysical data. He is a member of APPEGA and SEG. Jeffrey B. Thurston and Richard S. Smith received the 1997 SEG Best Paper in Geophysics Award for their paper Automatic conversion of magnetic data to depth, dip, and susceptibility contrast using the SPI (TM)! Method.

Seda Celebier
Seda is a Geologist and Environmental Impact Assessment (EIA) Specialist who holds a BSc in Geological Engineering and has backgrounds in the Environmental and Social Management Planning, Conservation and Rehabilitation, Data Management and Interpretation and Reporting in both Industrial and Mining settings.
Clive Foss

Clive Foss is a potential field geophysicist with particular interest in the magnetic field expression of remanent magnetisation. Clive received his BSc in geological geophysics at Reading University and a PhD at Leeds University in palaeomagnetic studies. Clive is now a Senior Geoscientist with CSIRO Earth Science and Engineering.

Recommended Reading

P.J. Gunn, D Maidment & P.R. Miligan, ‘Interpreting Aeromagnetic Data In Areas of Limited Outcrop’, AGSO Journal of Australian Geology& Geophysics Airborne Magnetics and Radiometric Survey Volume 17, Number 2, 1997

Jeffrey B. Thurston and Richard S. Smith ‘Automatic conversion of magnetic data to depth, dip, and susceptibility contrastusing the SPI (TM) method’ GEOPHYSICS, VOL. 62, NO. 3 (MAY-JUNE 1997); P. 807-813,4 FIGS

Alan B. Reid and Jeffrey B. Thurston ‘The structural index in gravity and magnetic interpretation: Errors, uses, and abuses’ GEOPHYSICS, VOL. 79, NO. 4 (JULY-AUGUST 2014); P. J61–J66, 3 FIGS., 1 TABLE. 10.1190/GEO2013-0235.1

Desmond FitzGerald, Alan Reid, Philip McInerney, ‘New discrimination techniques for Euler deconvolution’ Computers & Geosciences 30 (2004) 461–469

Jeffrey B. Thurston, Richard S. Smith, and Jean-Claude Guillon, ‘A multimodel method for depth estimation from magnetic data’, GEOPHYSICS, VOL. 67. NO. 2 (MARCH-APRIL 2002); P. SSS-S61,6 FIGS., 1 TABLE. 10.1 lSH)/l. I468616