Near Surface - Unconventionals

Exploring with Airborne Gravity Gradiometry



  Dr Asbjørn Nørlund Christensen (Nordic Geoscience, Melbourne, Australia)


  1 day


  Engineering – Airborne Exploration






  5 CPD points




Course description

The course combines a series of presentations on airborne gravity gradiometry (AGG) with hands-on exercises and class discussions. The objective of the course is to introduce attendees to AGG with a particular emphasis on its application to exploration for hydrocarbons and mineral resources.


Course objectives

Upon completion of the course, participants will have a deeper understanding of:

  • The differences and similarities between AGG and conventional gravity;
  • The current AGG technologies (FTG and FALCON) as well as the emerging new AGG technologies that may become available in the near future;
  • The sensitivity of the AGG technologies — what may and may not be detected — and how to design an AGG survey to deliver maximum value to their exploration programme;
  • The ways to interpret AGG data and how to integrate the interpretation with seismic and other geophysical data;
  • A number of case studies ranging from base metals to hydrocarbon exploration plays.


Course outline

  • Fundamentals of Airborne Gravity Gradiometry (AGG)
    • Basic theory of AGG
    • How AGG differ from ground-, marine-, and airborne-gravity.
    • Current and future AGG instruments
  • AGG data acquisition and processing
    • Sensitivity and detectability of AGG surveys
    • How to design an AGG survey
    • How AGG surveys are processed and what is delivered to you
  • Interpretation of AGG data
    • Regional mapping and qualitative interpretation
    • Inversion of AGG data and quantitative interpretation
  • Case Studies: AGG in petroleum exploration
    • Basin studies
    • Salt and sub-salt
    • 3D extrapolation of 2D seismic
    • Transition zones
    • Thrust zones
  • Case Studies: AGG in minerals exploration
    • Iron ore
    • Diamonds
    • Iron Oxide Copper Gold (IOCG) deposits


Participants' profile

The course is presented with a minimum use of mathematics and is intended for any exploration geophysicist/geologist interested in learning about airborne gravity gradiometry.


About the instructor

Asbjorn Norlund Christensen is owner of Nordic Geoscience Pty. Ltd., consulting world-wide on ground and airborne geophysics.

Working for BHP Billiton in the late 1990’s Asbjorn was actively involved in the initial development and deployment of the FALCON AGG system. He was worked on minerals exploration projects in Australia, Asia and Africa, and has managed research teams and technology companies.

His areas of interest are: geophysical technology development and deployment, potential fields, and the integrated interpretation of geophysical data for minerals and petroleum exploration. He has an MSc in Geophysics from University of Aarhus, Denmark and a PhD in Geophysics from Colorado School of Mines, USA. He is a member of EAGE, SEG, PESA and he is the Victoria Branch President of the ASEG. He is based in Melbourne, Australia.


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