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Water injection to defuse big quakes

by Jon Richfield
Tags: defuse, injection, quakes, water
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mfb
#19
Jul5-14, 09:58 AM
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Quote Quote by billiards View Post
I guess the other technical issue is what effect does doing this have on the stress regime somewhere further down the line? Are you not just shifting the problem onto someone else's doorstep?
How would that be different from natural earthquakes?
Jon Richfield
#20
Jul5-14, 10:17 AM
P: 258
@Billiards. "...shifting the problem onto someone else's doorstep? "
Reasonable thought, but not persuasive, I'd say. Once energy is spent, it is spent, so whatever has been removed by rattling one backyard cannot harm another backyard. Sure, distorting (or removing the distortion from) the rocks under my yard might permit (or force) your rocks to perform somewhat, but they would do so anyway if the BIG ONE struck as a result of my doing nothing, and your rocks would then have the un-bled energy to deal with all at once. They would perform more violently from a full sledgehammer blow than from energy bleeding from your neighbour's rocks a jiggle at a time. Bottom line remains: it looks very much as though ANYTHING we do is likelier to be beneficial than whatever we neglect to do.
billiards
#21
Jul5-14, 10:35 AM
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Quote Quote by mfb View Post
How would that be different from natural earthquakes?
The point is that if action you take does not fundamentally deal with the problem, then you are wasting your time.

Quote Quote by Jon Richfield View Post
@Billiards. "...shifting the problem onto someone else's doorstep? "
Reasonable thought, but not persuasive, I'd say. Once energy is spent, it is spent, so whatever has been removed by rattling one backyard cannot harm another backyard. Sure, distorting (or removing the distortion from) the rocks under my yard might permit (or force) your rocks to perform somewhat, but they would do so anyway if the BIG ONE struck as a result of my doing nothing, and your rocks would then have the un-bled energy to deal with all at once. They would perform more violently from a full sledgehammer blow than from energy bleeding from your neighbour's rocks a jiggle at a time. Bottom line remains: it looks very much as though ANYTHING we do is likelier to be beneficial than whatever we neglect to do.
What if we live along the same fault line and my backyard is preloaded with stress. You unzip the stress in your backyard and bring the stress in my back yard closer to failure. I'm now at risk from the big one happening in my back yard. Are you going to lubricate the whole fault line? Then what happens on the other side of the tectonic plate?
Jon Richfield
#22
Jul5-14, 11:19 AM
P: 258
Quote Quote by davenn View Post

They have no way of knowing exactly what is occurring several km's down. I see it as just way too risky to "play with fire" like that.
Dave, the point I am trying to convey is that knowing the little that we already know about what is happening next-door-but-straight-down leaves us confident that something big is brewing. We just don't know HOW big and precisely where and when. We also know that whatever large amount of energy is allowed to accumulate into catastrophe-prone stress is a certain disaster in waiting. Playing with fire in that mode can do no greater harm than what is certain anyway, and might very likely reduce the stress accumulation by leaking the energy elsewhere.

Whether we can do enough to make the effort worth while is a separate question, but the scenarios are believable enough to make it irresponsible to close our eyes to the options and neglect to play with that particular fire.

I am alive to the possibility, in fact the reasonable likelihood, that we are close to a BIG ONE and that some of our quakelets might trigger it, but if there happens to be nothing to trigger, there is nothing dreadful under the bed and nothing we could do would cause a serious quake. If something horrible happens in response to our fire games, it was going to happen anyway. and worse, just a bit later. The longer we wait the smaller the profit and the greater the harm either by us or by beneficent mother Nature.

Could you suggest a physical scenario in which our meddling creates something worse than the consequences of waiting for the maximal, natural, inevitable quake? Such an instance is probably the main thing I am fishing for, and so far I haven't had a nibble.
Jon Richfield
#23
Jul5-14, 12:47 PM
P: 258
Quote Quote by billiards View Post
The point is that if action you take does not fundamentally deal with the problem, then you are wasting your time.
Billiards, what you say here may be a truism, but is ninety degrees out of phase both with the topic and mfb's question:"How would that be different from natural earthquakes? ". Remember?
Firstly your response does not in any way deal with the question of whether either energy bleeding or triggering deals fundamentally with the problem, which in fact both patently do; they reduce the destructive energy available, and reduce the expected concentration of the energy into extra-destructive super-quakes or even into mid-sized quakes. Mostly you wind up with quakelets. And they even give you more options for bleeding the energy preferentially from vulnerable regions. For example, a few rural M7 quakes during the stress-building phase might snuff out city quakes further along the fault entirely, or reduce them to localised, moderate quakes. The effective bottom-line difference could be trillions of dollars per quake swarm in a region like Tokyo or SF.

In short, if your action has a reasonable prospect of fundamentally dealing with a problem on such a scale, then you had better risk wasting a bit of time!



What if we live along the same fault line and my backyard is preloaded with stress. You unzip the stress in your backyard and bring the stress in my back yard closer to failure. I'm now at risk from the big one happening in my back yard. Are you going to lubricate the whole fault line? Then what happens on the other side of the tectonic plate?
Bringing your back yard closer to failure is part of the point. Causing your rock to fail either piecemeal or gradually is at worst no worse than the BIG ONE that had been on its way, and might cause effects that even you would be prepared to accept, such as an aftershock swarm of benign quakelets. Lubricating the whole fault line would be ill-advised and pointless, but lubricating it in planned sections would be more like the appropriate strategy. Cheaper and safer. Don't you think? And anyway, I stand at least as great a chance that your backyard goes first and bring mine closer to the BIG ONE. You don't hear me complain do you? You see, I realise that I am probably better off than I otherwise would have been.

Errr... the other side of the tectonic plate??? Riiight...

Would you care to elaborate? Are you referring to some effect where the other side does nothing in a natural quake, but does something dreadful in a provoked quake? I don't know about losing me, but you certainly have lost someone there!
Jon Richfield
#24
Jul5-14, 01:24 PM
P: 258
Quote Quote by billiards View Post
Agree. But how do you incentivize someone to do it? The reward that you might save lives in the future is not enough IMO, at least not on a personal level, because you have to offset that with the risk that you could inadvertently take lives..
Selling never was my long suit, as you can tell. I leave incentives to other people to deal with. Doing my bit to ensure that at least a few informed people pass on the meme is all I can try for. (After all, I cannot possibly be the first to appreciate this obvious and unalterable truth about preempting the BIG ONE. )

But I am far from agreeing with your assertion " ...that you might save lives in the future is not enough". Rushing to warn people that a dam was failing might take a life either in a traffic accident, or in frantically shoring up the dam wall or evacuating the town. So, are we instead to sit on our hands because someone might get hurt in stopping the BIG ONE?

Not in THESE shoes!


Fair enough if we had the technology to make it 100% risk free.
Joke, right??? We don't have the technology to make it risk free for me to drive to work or eat brekker. So risking saving lives just isn't on???

But I would argue it could never be risk free until we could 100% predict earthquakes.
Fussy, fussy! 90% won't do, huh? How about 99%?

In that case we could take other strategies, like evacuation, to avoid disaster
Get real, man! Evacuating say, SF or LA IS a disaster from waaay back! Let's hear you estimate the death toll, the cost? How long would it take? How long would you allow before everyone trooped back, hale and hearty with their picnic baskets, to the smoking ruin? You think 9/11 was bad?
Watch this space!
Jon Richfield
#25
Jul5-14, 01:32 PM
P: 258
Oh BTW folks, a few of us have been concentrating on the injections with all their associated uncertainties as the only or main way to massage the quakelets into existence. Actually, I suspect that injection might be important in practice, but my entire discussion and proposal hardly nod in that direction; I don't care what means we use, and I suspect that I have better proposals for the initiative.

However, I don't want to hobble your collective creativeness, so before discussing any of my own thoughts on the subject, here is a challenge in the hopes of a flash of genius:
What would YOU propose as a means of affordably tickling the earthquake dragon?
davenn
#26
Jul5-14, 06:42 PM
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Dave, the point I am trying to convey is that knowing the little that we already know about what is happening next-door-but-straight-down leaves us confident that something big is brewing. We just don't know HOW big and precisely where and when. We also know that whatever large amount of energy is allowed to accumulate into catastrophe-prone stress is a certain disaster in waiting. Playing with fire in that mode can do no greater harm than what is certain anyway, and might very likely reduce the stress accumulation by leaking the energy elsewhere.
and the point I'm making is that "no one in their right mind would want to be responsible for the death of 1000's and the major destruction that ensued

Billiards, what you say here may be a truism, but is ninety degrees out of phase both with the topic and mfb's question:"How would that be different from natural earthquakes? ". Remember?
Firstly your response does not in any way deal with the question of whether either energy bleeding or triggering deals fundamentally with the problem, which in fact both patently do; they reduce the destructive energy available, and reduce the expected concentration of the energy into extra-destructive super-quakes or even into mid-sized quakes.

Unfortunately, I cant give you specific references, It was in a USGS video of some years ago after the Northridge, CA quake. Stress release on one section of the fault does transfer stress along the fault. So you really can be causing problems for some one else along the fault.


For example, a few rural M7 quakes during the stress-building phase might snuff out city quakes further along the fault entirely, or reduce them to localised, moderate quakes. The effective bottom-line difference could be trillions of dollars per quake swarm in a region like Tokyo or SF
see above

The only way injection to reduce stress could be done without the risk of setting off a major event is if it was started at the same time as the tectonics started ---> a couple of billion of years ago so that unknown high levels of stress never had a chance to build up in the first place.

Because you want to start injecting faults in the present day, you have no real idea of where a particular section of a fault sits in its stress range .... is it at a low range .... where injecting would be a safe thing and only produce quakes less that say .... M4, ? or somewhere intermediate where is could produce damaging events in the M4 - M6 range, or is it already at a point where its close to snapping and any minor lubrication of the locked section of fault will result in a major M7+ quake with catastrophic results ?

Currently, there are just too many unknown variables about what is occurring underground.


cheers
Dave
Borek
#27
Jul6-14, 04:29 AM
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This long stopped to follow the forum rules. I am guilty as well.

Topic locked.


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