Approximately half of the earth’s remaining oil reserves exist in limestone reservoirs. Using three-dimensional X-ray technology to study the ways in which oil and other liquids flow through rock, scientists from the University of Edinburgh and Heriot-Watt have conducted research that may increase our potential to recover oil from these deep rock formations.
Published in Proceedings of the National Academy of Sciences, the study received support from Petrobas and BG Group. The team of scientists and engineers carried out the research as part of the International Centre for Carbonate Reservoirs program, eventually discovering a previously undetected naturally occurring characteristic of oil that may aid its recovery from subterranean rock deposits. Researchers detected the process occurring within limestone’s complex pore structure, noting that it allowed oil droplets trapped in porous rock to move more easily though pore networks. During the process, flowing water breaks oil droplets into small fragments, thus making it easier to recover.
This development could increase oil reservoir yields and is especially applicable to operations in complex, multi-scale reservoir pore systems, such as those found in the pre-salt carbonate oil fields of Brazil. It also has the potential to help treat contamination in natural aquifers and aid the development of carbon capture and storage techniques.