Seismic forward modelling for shale gas characterisation in the Laurel Formation, north Canning Basin
Ebrahim Zadeh A , Reza Rezaee B and Mark Sams AA Ikon Science.
B Department of Petroleum Engineering, Curtin University.
The APPEA Journal 53(2) 452-452 https://doi.org/10.1071/AJ12063
Published: 2013
Abstract
The Carboniferous Laurel Formation is a thick, regionally extensive package of sand, shale, and limestone with significant liquids content. This study aims to investigate the relationship between total organic carbon (TOC) content and seismic attributes by forward modelling of seismic response to variations in TOC content and calibrating the models using available well and seismic data.
A regional relationship between acoustic impedance and TOC content has been established based on the TOC measurements of core samples taken from wells penetrating the Laurel Formation. This regional function has then been calibrated to the Sundown–1 well, which is located in the Bunda 3D seismic survey in the northern Canning Basin. The calibrated function has been used to estimate the acoustic impedance of the shale interval for a range of TOC values. Based on these acoustic impedance estimates, the reflectivities have been calculated and the synthetic seismograms for corresponding TOC values have been generated. A direct transformation of seismic amplitudes to TOC content has been achieved by plotting the AI against TOC and fitting the appropriate trend function to the data.
The seismic tuning effect has been modelled as an important cause of variations in amplitudes to be considered and compensated for in TOC estimates. A map of scale factors has been generated based on results of a wedge model to remove the seismic tuning effect from TOC estimates. The resulting TOC content map includes some interesting features that can be considered as shale gas sweet spots.
Ebrahim is a senior QI geophysicist for Ikon Science. He holds an MSc (exploration geophysics) from Iran. He has more than 13 years of experience in seismic acquisition, exploration, field development, and reservoir characterisation. He has gained experience in the Middle East, southeast Asia, and Australia. He has published several conference and journal papers and is interested in applications of QI techniques in exploration and development of conventional and unconventional resources. |
Reza Rezaee of Curtin University’s Department of Petroleum Engineering has a PhD (reservoir characterisation). He has more than 25 years of experience in academia. He has supervised more than 60 MSc and PhD students during his university career to date. He has published more than 120 peer-reviewed journal and conference papers and is the author of three books about petroleum geology, logging, and log interpretation. His research has been focused on integrated solutions for reservoir characterisation, formation evaluation, and petrophysics. Presently, he is focused on unconventional gas, including gas shale and tight gas sand studies. He is lead scientist for the WA: ERA (EIS) tight gas and shale gas research projects. He established Curtin University’s unconventional gas research group in 2010. |
Mark is quantitative interpretation manager for Ikon Science Asia Pacific. He is well known in Asia Pacific based on his 13 years in senior positions with Fugro Jason. He rings a strong reputation for technical competency in rock physics and quantitative interpretation. He has had an extensive research career, working with Mike Worthington at Imperial College London and for Petronas Research Malaysia. His work includes rock physics modelling, focusing on integrating data measured at different scales. He holds a PhD and an MSc (geophysics) from Imperial College London. He has authored, or co-authored, more than 25 peer-reviewed scientific papers and presented more than 50 papers at international conferences. He is an associate editor for Geophysical Prospecting and a reviewer for the EAGE annual conference. |
References
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