fracking need to be changed, because they are currently "unnecessarily restrictive".
In a report, which is published today (11 November) in the Quarterly Journal of Engineering Geology and Hydrogeology, the two academics added that current limits on vibration are so strict, that if applied elsewhere they would prevent heavy vehicles from driving past homes, or stop people walking on wooden floors.
They also said the risks of serious earthquakes reported to be caused by fracking activity is "considerably lower" than feared.
The report has been written by Dr Rob Westaway and Professor Paul Younger of the University of Glasgow's School of Engineering, and they feel that a new regulatory framework, like one similar to the rules which govern activities such as quarry blasting, would be more appropriate.
Dr Westaway explained: "Currently, the Department of Energy and Climate Change's regulation is that any fracking operation which induces surface vibrations greater than magnitude 0.5 on the Richter scale should be shut down immediately.
"That level of vibration is extremely low. To put it in perspective, if regulations for other vibration-causing activities were similarly restrictive you'd have to prevent buses from driving in built-up areas or outlaw slamming wooden doors.
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"By analysing the seismic waves which travel through the earth as a result of fracking activity, we've been able to determine a scale of activity which will create surface vibrations within those already allowed for by quarry blasting regulations.
"For example, induced earthquakes of magnitude 3 from fracking activities 2.5km below the earth's surface will create surface vibrations similar to the limits allowable from quarry blasting."
He added: "Conversely, induced earthquakes at the current UK regulatory limit of magnitude 0.5 would be expected to produce vibrations in a person's home that are smaller than those typically caused by the movement of buses or lorries past the end of their garden and comparable to many other widely-accepted forms of 'nuisance' vibration."
The academics have said that the largest possible fracture which could be created by current drilling processes on properly-surveyed land would be 600 metres long.
Professor Younger said: "We've determined that a fracture of that length created in a single rupture, which is very unlikely, would likely correspond to a maximum quake of magnitude 3.6. That might be sufficient to cause minor damage on the surface such as cracked plaster.
"Again, however, there is already regulation in place for compensation for similar incidents caused by RAF fly-bys or mining operations and we'd suggest it would make sense for similar schemes to be put into place for fracking."
Younger also commented that "the biggest cause of serious seismic incidents" isn't as a result of the drilling or the fracking process itself, but rather "the practice of disposing of waste water back into the borehole once the process is finished."
He said: "This washes away particles of sand holding open the fractures created during the process, which can cause earthquakes."
"In Britain, we've adopted longstanding EU groundwater regulations which bar subsurface disposal of wastewater completely, meaning there is no danger of this sort of event happening here. Instead, the water would be treated and disposed of safely elsewhere," he concluded.
Hydraulic fracturing, or fracking as it is commonly known, is a technique designed to recover gas and oil from shale rock. The process involves drilling down into the earth before a high-pressure water mixture is directed at the rock to release the gas or oil located inside.
(JP/IT)
