Shale Gas

Wurz wrote (see)

Apparently the tremors in the NW earlier in the year were caused by the fracking near Blackpool.  Apparently they won't happen again.  Any geologists/drillers care to give a brief laymans reason why not?

Because if they announced 'yeah, this is gonna happen a lot from now on, and it might get worse' people might be unhappy?

Seems like the Blackpool tremors were unexpectedly high. The Yanks have been using fracking to extract shale gas for some time, and there have been two noticable tremors linked to that activity and both were much weaker than the largest Blackpool one.

I don't believe there's any practical way of generating a big enough tremor to actually cause property damage in that location though. There would need to be a shockwave a good hundred times more powerful to be distructive enough to spill your pint, for example. Short of setting off nuclear weapons down there, I don't think the Bowland shale geology is unstable enough to cause that sort of event... the most recent study reckons worst case scenario would be powerful enough for people to notice, but pints would not be at risk.

Hmmm, I don't know feck all the geological effects of hydraulic fracturing but I'm always very sceptical about any claims or counter-claims by the energy industry.

That said, if the British Isles (and, specifically, northwest England) are sitting on vast reserves of shale gas that can be extracted without drastic longterm damage to the environment (as claimed), then I would prefer to exploit that energy source rather than see further desecration of our upland and coastal landscapes by inefficient and intrusive windfarming.

I thought that report on fracking hadn't been published yet but was iminent. If so how can anyone be so sure this is related to the fracking done in the northwest.

I'm for it but mostly because they are doing it in my old neck of the woods in Hesketh Bank. The news channels call in Banks but it is Hesketh Bank not Banks. I know because I actually recognise the area from the news. I have no qualms about Hesketh Bank disappearing into the earth in a load of fracking induced earthquakes if only they could keep it contained to Hesketh Bank and Tarleton I'd be most happy. Oh and noone is hurt of course. I'm not against those places but they are dumps or were when I was there.

Banks has good farm shops and garden centres / plant nurseries so deserves saving. Plus some farms in the Banks area  supplies Booths with veggies IIRC. Plus Banks was where either Rush or Aldridge lived when I were young and they played for Liverpool I believe. We cycled to gawp at his house once. Wasn't all that not like modern footballer's houses.

Lil it was on the TV news yesterday. Today's Torygraph

Sceptical B'stard, even if the gas find was massive I don't think timescales and policy would see any rapid change in present wind policy.  Plus there is the very uncertain points you raise about scale of the find and how benign it's extraction is.  After all this report was comissioned by the developer.

Wurz wrote (see)

... even if the gas find was massive I don't think timescales and policy would see any rapid change in present wind policy...

Sadly, I suspect you're right.

Wurz wrote (see)

After all this report was comissioned by the developer.

Hence my scepticism about it.

> I don't believe there's any practical way of generating a big enough tremor to actually cause property damage in that location though.

I think the risk is that wide-scale fracking causes collapse of the rock strata, which causes the tremors.  It's not the actual fracking process itself, I suspect.  See the BBC report:

'But the report, commissioned by energy firm Cuadrilla, also said the quakes were due to an "unusual combination of geology at the well site".'

My worry is that the structure down there may not be completely known (see above quote), or stable (despite seismic surveys that ought to be able to detect fracture lines etc.)  So you go down and break up the nice solid rock to release the trapped gas.  What is the structural rigidity of the remaining fractured rock (or is that frock...?)?  I suspect the theory is that no solid rock is being removed, so the volume remains constant, so it's not like you're undermining the foundations of your house which then falls into a hole (cf mine collapses).

From what I can gather, the 'quake caused some consternation at the rig (as in..feck...what was that).

Apparently, the process has been carried out over 1,000,000 times without an occurance of this magnitude - sure, they get wee shocks, but nothing this size (and to put this into perspective it was something like 2 on the Richter scale, which is described as "not felt but recorded" so hardly an earthmoving event).

I think it hides the debate on fossil fuels - sure there may be stacks of shale gas, but it is still a fossil fuel...nonrenewable and all that goes with it