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Reducing earthquake damage

Earthquakes and avalanches share characteristics that suggest a new approach to reducing earthquake damage. Both are the sudden release of gradually accumulated energy in a chaotic fractal structure. Exact time predictions will always be difficult and approximate, no matter how good the equipment. Both release forces that are difficult or impossible to resist.

Avalanche damage is commonly minimized by deliberately triggering avalanches when the area in danger has been evacuated. A small explosive shot from a cannon or dropped from an aircraft can trigger deadly avalanches when nobody is in the path of destruction. Since resistance or accurate prediction of earthquakes will always be difficult or impossible perhaps we could minimize their harm by trying to trigger them like avalanches.

An announcement could be broadcast and published for weeks ahead of time that on a specified Sunday afternoon at a specified time there might be an earthquake. People should be outside their homes with their fire extinguishers handy and their utilities shut off. Drivers should pull off the road and boats should be moved into open water. Hospitals and fire departments should be prepared.

The damage and loss of life if an earthquake happened under these conditions would much less than if it happened by surprise. The energy would be released, greatly reducing the likelihood of another earthquake in the near future. Repeated on an annual basis this could release accumulated energy as a series of smaller earthquakes instead of a few larger ones, further reducing the destruction. It would also be an earthquake drill; people would know what to do if warning signs were detected at any other time.

A further advantage is that seismologists could make special preparations to observe the vibrations from the trigger and the resulting earthquake. If the explosives are arranged in long straight lines and set off simultaneously then interference patterns could be used to map the deep structure of the earth in the region of interest. The Soviet Union is believed to have used nuclear explosives for deep earth seismographic mapping in this way. This would improve our understanding of the fault zones and guide future placement of triggering explosives.

The engineering problems are daunting. Our knowledge of the deep structures is not detailed enough to tell us the best places for the explosives. The best places will often be deeper than we can drill. The amount of explosives needed is much more than we have. Several simultaneous nuclear explosions would be our best chance. They will be too far below the earth to leak radiation to the surface and there are surplus warheads available that must be disposed of. The only encouraging note is the smallness of the explosives needed to trigger avalanches.

The social problems are also daunting. People hurt by a triggered earthquake will blame the responsible agency even though the earthquake was inevitable. Since that earthquake might not have happened in their life times their complaints may have merit.

We may never be able to accurately predict or effectively resist avalanches but we routinely minimize their damage by triggering them. We may never be able to accurately predict or effectively resist earthquakes but we may be able to someday minimize their damage by triggering them.