Earthquake prediction

[Shakir]

Hello PF

Why are scientists still unable to predict earthquake? Will it be possible to predict earthquake? Are there any promising research going on?

If only we could know when earthquake was going to hit, how many lives could have been saved!

 

[mfb]

Predicting earthquakes is a very hard problem. What scientists can do is a long-term prognosis: study the fault lines, their motion, pressure and so on. This often gives a prediction like "we expect a magnitude X earthquake within the next years". Those predictions can be quite reliable if the system got enough attention (especially at the US East Coast and in Japan). Pressure builds up slowly until the ground breaks. The trigger of large earthquakes can be very small and therefore hard to predict.

If only we could know when earthquake was going to hit, how many lives could have been saved!

The regions where earthquakes happen are well known. Just build houses solid enough to withstand those earthquakes. It makes the houses more expensive, but they save lives, and they don't have to be rebuilt after every earthquake.

The 2010 earthquake in Haiti, with magnitude 7.0, killed 100,000 to 200,000.

As comparison, Japan gets hit by about 2 magnitude 7 earthquakes per year - typically with 0 to 5 casualties.
Even the 2011 earthquake, one of the strongest ever recorded, didn't lead to large damage or casualties - at 100 times the energy of a magnitude 7 earthquake. The tsunami did kill many, but that is a different topic.
Building houses properly matters.

 

[Alienaftermint]

Helium levels rising in ground water may be a possible indicator.

 

[Evo]

Helium levels rising in ground water may be a possible indicator.

Apparently not.

The observations of short-term decreases in helium soil-gas concentrations along the San Andreas Fault in central California have been correlated with subsequent earthquake activity. The area of study is elliptical in shape with radii approximately 160×80 km, centered near San Benito, and with the major axis parallel to the Fault. For 83 percent of theM>4 earthquakes in this area a helium decrease preceded seismic activity by 1.5 to 6.5 weeks. There were several earthquakes without a decrease and several decreases without a corresponding earthquake. Owing to complex and unresolved interaction of many geophysical and geochemical parameters, no suitable model is yet developed to explain the observations.

And the decreases were not consistent enough to be a predictor.

http://link.springer.com/article/10.1007/BF00874605

 

[jsgruszynski]

Hello PF

Why are scientists still unable to predict earthquake? Will it be possible to predict earthquake? Are there any promising research going on?

If only we could know when earthquake was going to hit, how many lives could have been saved!

Predicting earthquakes falls into the same physical problem as as predicting failures and lifetimes of engineered "things". Basically you have to collect a lot of empirical data, crunch it just right with the correct associated data such as time of historic failure, and then all you can ever get in the end is statistic probability of when and how.

You can't get a specific result for a specific circumstance (equivalent of saying: "This part will absolutely fail on January 25, 2050" or there will be an earthquake precisely at the date). The best you can get is: "the most likely failure will be that date but plus-or-minus 25 years for the 1st standard deviation if you have N identical parts being used under exactly the same stresses". That's as good as it gets for predicting failures of engineered "things" but you don't even have equivalent situations with quakes.

The problem for earthquakes is physically identical, i.e. you are looking for a series of materials failures that cascade with a semi-scale-free event that you have a name for (quake or part failure), BUT you do not have access to even 10^-9 as much data that is barely a statistical sample as we would have for a manufactured part for failure analysis because the critical materials are deep in the Earth rather than in our hands.

It's a really tough problem. And it will likely always be a statistical answer (kind of like it is now). But probably a great eternal PhD thesis.