Well, dears, yes and no.
Yes, because Elswick targeted a shallow sandstone formation and was a single vertical well; and no because they both involve drilling wells and fracture stimulation.
I often see Cuadrilla and other shale gas proponents being criticised for using the Elswick analogy, as if they’re attempting to suggest that fracking for gas in shale rock will be exactly the same.
But that’s not what they’re saying at all, poppets: when they point to Elswick, they’re really just trying to give an impression of what a shale gas well might one day look like, after the relatively short period of construction and fracking has finished and all that’s left to see is the ‘Christmas Tree’ at the surface.
Now, sweeties, when people try to claim that the Elswick experience is vastly different from what’s planned in the extraction of Lancashire’s shale gas because of differences in scale – especially concerning the volumes of fluid used to fracture the rock – they mostly fail to point out just how similar the volumes really are.
John Hobson and his friend Mike Hill of the anti-fracking campaign group, Defend Lytham, are fond of telling us how Elswick was fractured using just 163 m3 of fluid compared to the many thousands of m3 of fluid needed to frack a shale well. They also refer to modern-day fracking as ‘High Volume Hydraulic Fracturing’ or HVHF – a definition that isn’t used by the onshore oil and gas industry.
I believe they do so in order deliberately to create the rather false impression that all those thousands of m3 of fluid are injected all in one go, pumpkins, when that’s not true at all. And here’s why:
In the extraction of shale gas, E&P companies will first drill a vertical well and then, in the target shale layer, a horizontal well. This will be hydraulically fractured in several stages, 30 being common in the US. Dependent on the identified fracture mechanics of the rock, each of these stages will be stimulated using between 300 and maybe 600 m3 of fluid, so between 9,000 and 18,000 m3 in total my loves.
But it’s not all injected at once. In many ways, you can think of those individual fracture stages a little like individual wells, dears – just accessed without the need for 30 separate surface penetrations.
Why do opponents of shale gas like to give the impression that the fluid is injected underground at once? Well, poppets, because that suits their narrative when it comes to claiming that the high volumes used will trigger tremors and that the volumes of fluid themselves could cause a loss of well integrity.
The reality, of course, is that operators will introduce fluid in small lots, giving them chance to adequately monitor for any seismic activity and prevent any damage to the well casing.
30 vertical wells drilled and fractured at Elswick, using the figure given by John and Mike, would use 4,890 m3 of fluid – putting it much more on a par with a single shale gas well using the lower end of my range. Yes, that’s still less than shale fracking, but that’s only because the sandstone rock is more permeable.
As you can see, cherubs, when viewed like this, it’s apparent that all this talk of HVHF and concerns over scale is really just over stating the facts. Elswick and modern day shale operations really aren’t all that different at all.
Until next time xxx