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GeoGeoGeoGeo OP t1_jdjgup0 wrote

Reply to comment by open_door_policy in The largest recorded earthquake in Alberta's history was not a natural event, but most likely caused by disposal of oilsands wastewater, new research has concluded. by GeoGeoGeoGeo

The following is provided from the USGS:

>FICTION: You can prevent large earthquakes by making lots of small ones, or by “lubricating” the fault with water.

>Seismologists have observed that for every magnitude 6 earthquake there are about 10 of magnitude 5, 100 of magnitude 4, 1,000 of magnitude 3, and so forth as the events get smaller and smaller. This sounds like a lot of small earthquakes, but there are never enough small ones to eliminate the occasional large event. It would take 32 magnitude 5's, 1000 magnitude 4's, OR 32,000 magnitude 3's to equal the energy of one magnitude 6 event. So, even though we always record many more small events than large ones, there are far too few to eliminate the need for the occasional large earthquake.

>As for “lubricating” faults with water or some other substance, if anything, this would have the opposite effect. Injecting high-pressure fluids deep into the ground is known to be able to trigger earthquakes—to cause them to occur sooner than would have been the case without the injection. This would be a dangerous pursuit in any populated area, as one might trigger a damaging earthquake.

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l4mbch0ps t1_jdl2qrr wrote

The last paragraph is sort of missing the mark though - the whole idea would be about releasing the quake earlier so its smaller than the future natural quake.

Not saying that the practice would work, but that paragraph doesn't represent the issue well, imo.

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LadyAstronaut t1_jdlakru wrote

But would the lubricant make it worse thus counter acting the benefit of triggering the quake sooner?

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RekindlingChemist t1_jdm6n39 wrote

first paragraph is missing the mark too, IMO. think about thousands of pressure cookers exploding at various pressures. it's not that "it's never enough explosions to prevent big one", it's more "there's always some strong enough cooker to blow at much bigger pressure". And lubricating should work much like safety valve, lowering pressure on which blowing occurs at every single cooker.

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mortaneous t1_jdmgmhv wrote

The problem is also that you can't necessarily control the magnitude of your induced earthquake. There would always be a chance that trying to trigger a bunch of M4's would accidentally get you an unexpected M5 or M6, and it's likely that the chance is unacceptably high given the number of quakes you have to induce to release enough energy for preventing the bigger ones.

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Manisbutaworm t1_jdlm5gv wrote

But if we can make earthquakes happen sooner we can choose a better moment of our choice. So we can prevent one ruining your weekend.

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