Assessment of shale gas pore systems
Adnan Al Hinai A , Reza Rezaee A , Lionel Esteban B and Hanieh Jafary Dargahi AA Curtin University.
B CSIRO.
The APPEA Journal 54(2) 531-531 https://doi.org/10.1071/AJ13104
Published: 2014
Abstract
Assessing shale gas petrophysical properties is a major challenge in the industry mainly due to its ultra-low matrix permeability. The ability of a formation to convey fluid through a porous media ultimately depends on the pore geometry and pore network. Shale pore geometry is acknowledged as being exceptionally complex and limited research has been done on the characterisation of pore networks of shale formation because of constraint in sampling, measurement resolution, and the highly heterogeneous nature of the rock. This study focuses on characterising a Permo-Triassic shale gas reservoir in the Perth basin, WA by assessing pore structures, using mercury injection capillary pressure (MICP), nuclear magnetic resonance (NMR), and scanning electron microscopy (SEM). MICP porosity corresponding to total connected porosity showed a narrow range 3–3.5%. Samples with the lowest peak radius had the lowest permeability and least percentage of macro-pore volumes indicating poor connectivity. T2 NMR response from partially saturated samples has a mono-modal distribution centred around 0.35 ms with an average of 3% porosity. Two populations are observed from brine saturated samples and a shift in the T2 peak toward longer T2 between 0.43 and 0.56 ms. The specimens are also studied by using SEM to identify different types of pores. This indicated that higher proportion of interparticle pores is promising a higher porosity and, in contrast, the specimen with dominant intraparticle pores is representative of low porosity. The combination of MICP, NMR, and SEM is an ideal approach to overcome their individual limits on pore size resolution and external influences.
Adnan Al Hinai is a PhD student at the Department of Petroleum Engineering of Curtin University. His research focuses on pore network modelling of gas shales reservoirs to investigate fluid flow mechanisms. His study examines various techniques to obtain shale gas flow properties, FIB/SEM images to reconstruct a 3-dimensional model of the original pore, nuclear magnetic resonance to assess the pore size distribution, and mercury injection tests to determine pore throat sizes. Adnan was awarded his Master’s degree in petroleum engineering in 2010, after completing his BSc in mechanical engineering in 2008 from Curtin University. |
Reza Rezaee is an associate professor at Curtin University’s Department of Petroleum Engineering. With a PhD in reservoir characterisation, he has more than 25 years’ experience in academia. Reza has supervised more than 60 MSc and PhD students during his university career to date. He has published more than 120 peer-reviewed journals and conference papers and is the author of three books on petroleum geology, logging, and log interpretation. Reza’s 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—and is the lead scientist for the Western Australian Energy Research Alliance (WA:ERA) Exploration Initiative Scheme (EIS) Tight Gas and Shale Gas research projects. He established Curtin University’s Unconventional Gas Research Group in 2010. |
Lionel Esteban is a petrophysicist at CSIRO with experience in conventional-unconventional petroleum reservoirs, working on experimental paleomagnetism-environment magnetism, flow properties, thermal, electrical, and electro-magnetic properties, and all integrated/calibrated against logging analysis/interpretations. His present research focuses on low permeability reservoirs (shales/gas shales, sediments, and tight gas) to understand clay mineral relationships with mechanical and petrophysical parameters controlling the flow properties and sealing capacity. He also works on geothermal reservoirs (pre-salt), carbonates and iron ore deposits to characterise fluid-rock interactions. Lionel is involved in several IODP/ODP expeditions targeting gas hydrates and active tectonics environments, combining experimental, and logging data. |
Hanieh Jafary Dargahi is a PhD candidate in Curtin University’s Department of Petroleum Engineering. She is working on identifying the shale-gas potential of the Perth Basin in cooperation with the shale-gas research group. Hanieh’s areas of interest are geology, petrography, sequence stratigraphy, and organic geochemistry. She has published four journal papers and two peer-reviewed conference presentation. Presently, Hanieh is studying under the supervision of Dr Reza Rezaee in Curtin University’s shale-gas research group. |
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