Safer fracking thanks to new early warning system

New technology developed at the University of Nottingham could be used as an early warning system to make fracking safer. The surveying software – PUNNET GEO – can provide a detailed picture of where hidden fractures beneath the earth’s surface might lie and has the potential to replace current ground-based, invasive and expensive exploratory methods. The Intermittent Small Baseline Subset (ISBAS) method adapts the currently used satellite radar technology and extends it to rural areas by taking stacks of radar images and identifying transient points in the landscape against which changes over time can be measured. “The ISBAS method is based upon a technique called InSAR that essentially analyses the difference between two radar observations at different times and can observe any change in motion of the land surface between the two dates,” Dr Andrew Sowter told Laboratory News. “This works very well if the land is covered in buildings or rocks as nothing much changes for them except when they move, so they tend to be ideal subjects.” “When we have a lot of vegetation in an area we see constant change due to growth, a thick canopy or agricultural activity so it is usually very difficult to spot any underlying motion. Rapid change is a characteristic of vegetation but there are always some, maybe few, points within that don’t change as much and actually move with the ground.  What these are – breaks in the canopy or a scarcity of leaf cover – we don’t completely know but ISBAS is able to spot these points and pull out the underlying land movement to give a more complete picture of deformation over an area than possible previously.  In this way our system gives an unrestricted view of the deformation that occurs over our land and to our knowledge no other system is able to give such a complete picture.” PUNNET GEO will allow surveyors to develop a detailed map of land movement over a large region and to identify potential locations of fault lines which could be associated with seismic activity. It could help local authorities and operating companies in deciding on suitable fracking sites, and allay public fears about the damage that could be caused by ground tremors. The technology is already being used by the British Geological Survey, who has purchased a development license of the software from the University. “The team at BGS have been there every step of the way, encouraging me and interpreting and testing the results using their considerable expertise in geology and remote sensing,” Sowter said. “I can honestly say that I would not be so confident about the outcome of my research without their support and I thank them enormously.”