Producibility and commerciality of shale resource systems: contrasting geochemical attributes of shale gas and shale oil systems
Basim Faraj A and Daniel Jarvie BA Tamboran Resources.
B Worldwide Geochemistry LLC/Energy Institute at TCU.
The APPEA Journal 53(2) 469-469 https://doi.org/10.1071/AJ12080
Published: 2013
Abstract
Increasing the producibility of petroleum from shale is a key challenge for this decade and beyond. While understanding of producing petroleum from shales has advanced rapidly during the past decade, many unknowns remain. In addition, fundamental differences remain between high-thermal maturity shale gas systems (gas-window shales) and oil-window shales. Although it is shown that oil is produced from the shale matrix similar to gas shales, it is not known what improvement to recovery factors should be expected due to the fundamental differences and uniqueness of shale oil systems.
Some of the challenges in early exploration of shales in the oil window are related to the loss of oil from rock samples (cuttings, core), sample processing, storage conditions, sample preparation, oil type, API gravity, gas–oil ratio (GOR), rock lithofacies, and analytical conditions. It is shown that old cuttings may lose up to 300% of their free oil content simply due to evaporation, even in tight shale with black oil having a GOR of about 500 scf/bbl. When cuttings are compared with RSWC or core chips, the loss increases to almost 500%.
Projection of oil content to match measured GOR values of oils or even extracts of organic-rich tight shales allows prediction of this oil loss—this impacts calculations of original oil in place (OOIP) and, hence, hydrocarbon recovery estimates from such systems.
Basim Faraj has been trained and worked as an exploration geochemist in conventional and unconventional oil and gas reservoirs. He has worked on projects in Jordan, Japan, Canada, USA, and Australia. He obtained a PhD (1995) from the Centre for Microscopy and Microanalysis and the Earth Sciences Department, UQ, Australia. In 2002, he completed the first shale study in the Western Canada Sedimentary Basin for the Gas Technology Institute. He is the chairman for the annual shale gas conferences organised by the Canadian Institute since its inception in 2005. Furthermore, he has been at the forefront of coalbed methane research and exploration since his work with BHP Coal in Australia and the University of Queensland. He has also worked as a shale gas and coal bed methane consultant for several energy companies in Calgary. Between 2005 and 2010, he was the unconventional gas specialist at Talisman Energy. He is now VP new ventures, Tamboran Resources Pty Ltd in Calgary. |
Dan is a shale geochemist at EOG Resources and Energy Institute at TCU. |
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