Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
The APPEA Journal The APPEA Journal Society
Journal of Australian Energy Producers
RESEARCH ARTICLE (Open Access) (Non peer reviewed)

Potential field interpretation and modelling in the deep-water Otway Basin

Yvette H. Poudjom Djomani A * and Merrie-Ellen Gunning A
+ Author Affiliations
- Author Affiliations

A Geoscience Australia, Canberra, ACT, Australia.

* Correspondence to: yvette.poudjomdjomani@ga.gov.au

The APPEA Journal 62 S487-S491 https://doi.org/10.1071/AJ21209
Accepted: 10 March 2022   Published: 13 May 2022

© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of APPEA. This is an open access article distributed under the Creative Commons Attribution 4.0 International License (CC BY).

Abstract

The NW–SE trending Otway Basin is a well-established hydrocarbon province with onshore and shallow-water offshore discoveries. However, the deep-water offshore is underexplored due to the sparsity of data in the past. New 2D seismic, gravity and magnetic data, acquired during the 2020 Otway Basin Seismic Program, were combined with legacy seismic data to improve the understanding of this part of the basin. The new data have been processed and integrated with existing open-file data to derive Moho and lithosphere–asthenosphere boundary surfaces. Additional wavelength filtering of the newly acquired magnetic and gravity data, using constraints from seismic data, provides valuable information on the geometry and the spatial extent of igneous rocks in the deep-water basin. While extrusive igneous rocks and related intrusive rocks in the Otway Basin can be inferred from seismic reflection data, the new magnetic and gravity data provide additional constraints that help to map their distribution across the basin.

Keywords: deep-water, gravity, high-pass filter, hydrocarbon prospectivity, igneous rocks, magnetic modelling, magnetics, Otway Basin, tilt angle, wells.

Yvette Poudjom Djomani is a Geophysicist with over 25 years of experience. She joined the Mineral System Branch of Geoscience Australia in 2016 working on magnetic, radiometric and gravity survey data quality control and assurance. Since July 2021, she has been working in the Offshore Energy System Branch on potential field data processing and enhancement, and integration with seismic data to help map the distribution of igneous rocks in the offshore Otway Basin. Yvette completed a Bachelor Degree in Science at the University of Yaoundé (Cameroon), a PhD in Geophysics at the University of Paris XI (France) and an MBA from the Australian Institute of Business (Adelaide). She has worked in academia, industry sector and government agencies. Yvette is the current Treasurer of the Federal Executive of the Australian Society of Exploration Geophysicists (ASEG). She is also the Chair of the Gender Equity Network at Geoscience Australia.

Merrie-Ellen Gunning has over 20 years of experience in the Oil and Gas industry where she has performed a diverse range of roles from strategic planning, business development and operations management, to technical roles specialising in Geophysics and Exploration. Added to this is 5 years of experience in the aluminium industry across the value chain from extraction, mining bauxite and nepheline, through refining alumina to smelting. In addition to her extensive knowledge of industry in Australia, her experience has included postings to Indonesia, Norway, the US, Russia and Singapore, and overseeing operations across the world. She has an MBA from Melbourne Business School and a Bachelor of Applied Science in Geology. Merrie-Ellen joined Geoscience Australia in August 2015 and has worked on a wide range of prospectivity and CO2 storage projects, leading the Energy Systems Branch throughout 2017 and is currently Director of Offshore Energy Systems.


References

Hackney R, Romeyn R, Orlov C (2015) Interpretation and modelling of new Browse Basin airborne magnetic data for igneous rocks and basement. ASEG Extended Abstracts 2015, 1–4.
Interpretation and modelling of new Browse Basin airborne magnetic data for igneous rocks and basement.Crossref | GoogleScholarGoogle Scholar |

Karvelas A, West T, Nicholson C, Abbott S, Bernardel G, Mitchell C, Nguyen D, Gunning M-E, Borissova I, Schenk O (2021) New insights into the deep-water Otway Basin – Part 2. Tectonostratigraphic framework revealed by new seismic data. The APPEA Journal 61, 657–664.
New insights into the deep-water Otway Basin – Part 2. Tectonostratigraphic framework revealed by new seismic data.Crossref | GoogleScholarGoogle Scholar |

Meyer B, Saltus R, Chulliat A (2017) EMAG2: Earth Magnetic Anomaly Grid (2-arcminute resolution) Version 3. NOAA. (National Centres for Environmental Information)
| Crossref |

Miller HG, Singh V (1994) Potential field tilt—a new concept for location of potential field sources. Journal of Applied Geophysics 32, 213–217.
Potential field tilt—a new concept for location of potential field sources.Crossref | GoogleScholarGoogle Scholar |

Moore AMG, Stagg HMJ, Norvick MS (2000) Deep-water Otway Basin: a new assessment of the tectonics and hydrocarbon prospectivity. The APPEA Journal 40, 66–84.
Deep-water Otway Basin: a new assessment of the tectonics and hydrocarbon prospectivity.Crossref | GoogleScholarGoogle Scholar |

Morse M (2010) Potential field methods prove effective for continental margin studies. AusGeo News 98, 1–4. Available at https://www.ga.gov.au/ausgeonews/ausgeonews201006/geology.jsp

Nicholson C, Abbott S, Bernadel G, Gunning ME (2022) Stratigraphic and structural architecture of the Upper Cretaceous in the deep-water Otway Basin – implications for frontier hydrocarbon prospectivity. The APPEA Journal 62, S467–S473.
Stratigraphic and structural architecture of the Upper Cretaceous in the deep-water Otway Basin – implications for frontier hydrocarbon prospectivity.Crossref | GoogleScholarGoogle Scholar |

Sandwell DT, Smith WHF (2009) Global marine gravity from re-tracked Geosat and ERS-1 altimetry: ridge segmentation versus spreading rate. Journal of Geophysical Research: Solid Earth 114, B01411
Global marine gravity from re-tracked Geosat and ERS-1 altimetry: ridge segmentation versus spreading rate.Crossref | GoogleScholarGoogle Scholar |

Schenk O, Karvelas A, West T, Kornpihl D (2021) Otway Basin Regional Study report. Available at https://www.ga.gov.au/nopims/releases/otway-basin-regional-study-report