Mapping horizons and fracture patterns in coal measures using magnetics for coalbed methane exploration in Queensland
Irena Kivior A , Stephen Markham A , David Warner B and Leslie Mellon AA Archimedes Consulting.
B DSWPET Pty Ltd.
The APPEA Journal 55(2) 443-443 https://doi.org/10.1071/AJ14078
Published: 2015
Abstract
High resolution magnetic data has successfully been used to map the top and base of coal measures, related faults and fracture patterns across the Red Hill area in the northern Bowen Basin, eastern Australia. A horizon mapping technique, based on energy spectral analysis (ESA), was used to detect magnetic susceptibility contrasts that were laterally merged to form two magnetic interfaces, corresponding to the top of the Fair Hill Formation and base of the Goonyella Middle Seam in the Permian Moranbah coal measures. The depth estimates were made at stations on a regular mesh of 400 m × 400 m and at nine wells. The final detailed mapping of both horizons was constructed from spectral depth estimates on a regular mesh of 100 m × 100 m.
Major faults, associated structures and fractures were mapped in 3D from the magnetic data by using automatic curve matching (ACM). This technique was applied to detect single magnetic anomalies produced by inter-sedimentary sources. These results were used to interpret magnetic lineaments in, above and below the coal measures to produce a rock fabric model.
The results obtained from the interpretation of the magnetic data are consistent with structures mapped from existing seismic and well data. The mapped rock fabric was also confirmed by well results to be a fair representation of the open fracture set, which has an orientation that is consistent with the existing stress regime.
Irena Kivior obtained a master of engineering from the Academy of Mines and Metallurgy in Krakow, Poland, and a PhD in geophysics from the University of Adelaide. She worked for mineral exploration companies and in the coal industry after migrating to Australia. After her PhD and post-doctorate studies, she established Archimedes Consulting, where she is director and principal geophysicist. Member: AAPG, SEG and EAGE. |
Stephen Markham graduated from Flinders University with a BSc (Hons) and also completed an MSc in geophysics. Stephen’s research focused on the application of high resolution aeromagnetic data across the Otway Basin. Since 1997, he has worked for Archimedes Consulting as a senior geophysicist and he is now chief geophysicist, working on the analysis of potential field data over sedimentary basins. Member: ASEG. |
David Warner graduated from Armidale University with a BSc (Hons) in geology and an MSc in petroleum geology from Imperial College, London. David has 42 years’ experience working in the oil and gas industry worldwide. From 2000 to 2009, he worked as team leader of the Santos unconventional reservoir group, developing new unconventional plays, evaluation procedures and completion techniques in the Cooper Basin. After leaving Santos, David established DSWPET Pty Ltd, an independent consulting company specialising in onshore Australian exploration and production. Member: AAPG and SPE. |
Leslie Mellon graduated from the University of South Australia with degrees in geology and hydrology and she completed her post-graduate studies in groundwater hydrology at Flinders University. After graduation, she worked as a geologist in mineral exploration. Since 2010, Leslie has worked at Archimedes Consulting as a structural geologist and she is now a project coordinator. |
References
Gillam, D., Flottmann, T., and Hillis, R., 2004—Natural Fracture Characterisation in a Coal Measure Succession: An Analogue for Coal Seam Methane and Tight Gas Reservoirs. PESA Eastern Australian Basins Symposium II, Adelaide, SA, 19–22 September.Kivior, I., Chandola, S.K., Lee, B.C., Eng, B.K., Nordin, A., Markham, S., and Hagos, F., 2012—Regional Mapping of Basement and Sedimentary Interfaces in the Deep Waters of the Andaman Sea Basin Using Marine Magnetic and Gravity Data. AAPG International Conference & Exhibition, Singapore, 16–19 September.
Kivior, I., Yates, S., Markham, S., Vaughan, F., and Damte, S., 2007—Imaging Basement & Intra-Sedimentary Horizons with Spectral Methods Applied to HRAM Data in Sirt Basin, Libya. EGM International Workshop (EAGE), Capri, Italy, 15–18 April.