Firstly, we don't leave ';big voids';; the oil is in spaces in porous rock, a bit like concrete breeze-blocks. Vast caverns can't collapse.
However, oil drilling changes the pressure regime, initially dropping it when the oil is extracted, and often raising it again later when high pressure water is injected to improve yields. The rock itself is slightly elastic, and there is some settlement, sometimes a few metres, again changing the stress.
There are large numbers of faults, and changing the stress pattern can result in yield along some of them, causing earthquakes.
Mining, and even constructing large reservoirs can have a similar effect.
Most of these quakes are of ';nuisance value'; at worse, though in the 60s an attempt to dispose of toxic liquids deep in the earth below Nevada was stopped, not because of environmental concerns but because they were getting too many damage claims due to minor earthquakes.
Big quakes, and especially volcanism, are on a different scale however, originating in the deep crust and mantle, up to hundreds of kilometres down and far beyond the range of even the most ambitious drilling project. There is no indication that drilling could have a measurable effects on those.Will oil drilling increase earthquake activity?
I think they pump water in it's place as a part of the oil extraction process.
But that's nothing to do with the amount of resources remaining. Oil takes millions of years to develop - we're using it up a tad quicker than that.
it seems that the tragic boxing day tsunami may have been directly linked to the research into oil.many strange things happened just before the tragedy,including wales beaching themselves.
I have heard about a theory that depleted oil reservoirs will re-fill in time, as oil gradually flows up into them again from a vast reservoir at the centre of the Earth. Anyone who believes this has no need to worry about earthquakes and running out of oil. Seriously though, there's a lot of good information about hydrocarbon reserves at www.bp.com, click the link.
PS Hopefully we won't need to burn all of it anyway. As an oil sheikh philosophised once, ';The stone age didn't end because people ran out of stones';.
No Im afraid this is not the case. Geologists would not allow drilling if the area was unstable. However, in no way can the drilling of what are effectively tiny pin pricks in the worlds surface lead to the shift of continental plates. i.e. the eurasia plate that covers europe and asia and floats on a bed of magma isnt gonna be disturbed by a bit of drilling
This is not a real fact. As earthquake were there when there was no drill of oil. We can say that oil may finish one day, the way we use it on a large scale.
Since the oil is under masive pressure, much of it can be released before the cavity becomes a 'void'. Usually, the well is filled with sea-water when drilling off-shore, but in comparison, seismic activity is on a scale that is almost incomparible to drilling. (Like the chance of throwing a tiny piece of gravel onto the roof and expecting your whole house to shudder!!)
It's really just the effect of burning the oil and releasing the carbon from it into the atmosphere that creates a real threat.
Oil is not just sloshing around in caverns underground.
Certain rocks are porous - they have little holes in them - and so can contain liquid, such as Oil or water. When they extract the Oil, they draw it through the gaps in the rock. This only extracts some of it - and so they pump water or steam down to help push it through and clean more of it off the rock.
So it doesn't cause more tectonic activity - earthquakes, volcanoes, etc. - as it isn't actually affecting the rocks themselves, just the liquid in them.
drill hole, pump water in under pressure forces oil out of hole, void filled. conservationists they are not. regards LF
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