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earthquake prediction

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earthquake prediction

  1. 1. • Earthquakes have occurred since the planet came into being and yet we are still unable to predict with even half decent accuracy their magnitude, timing or location. Government and academic departments around the world have continued their hard work and in recent years scientific evidence has emerged which one day could save thousands of lives.
  2. 2. • Earthquake prediction– It is usually defined as the specification of the time, location, and magnitude of a future earthquake within stated limits and particularly of "the next strong earthquake to occur in a region.
  3. 3. •Types of prediction • Deterministic prediction • Statistical prediction
  4. 4. •Can we predict earthquakes ?• Scientists have tried lots of different ways of predicting earthquakes, but none have been successful. They have a pretty good idea of where an earthquake is most likely to hit, but they still can't tell exactly when it will happen. • However, the probability of a future earthquake can be calculated, based on scientific data. Scientists at the US Geological Society (USGS) estimate that the probability of a major earthquake occurring in the San Francisco Bay area over the next 30 years is 67%.
  5. 5. •Why can’t we predict earthquakes? • So far, scientists haven't been able to find a signal for earthquakes - there is no obvious sign to say that an earthquake is coming very soon. Vibrations can be detected just before an earthquake occurs, but this doesn't give enough time for people to escape. • The processes that cause earthquakes mostly occur far below the Earth's surface. There are many tectonic plates - sections of the Earth's crust that rub together and cause earthquakes - and their interactions are complex. This makes earthquakes very hard to study.
  6. 6. •Will we ever be able to predict earthquakes?• Scientists at USGS and other organisations are working hard to developing methods which will predict earthquakes. Hopefully, scientists has progressed significantly in recent years and may soon help save thousands of lives.
  7. 7. Image of California earthquake which was successfully predicted
  8. 8. •What constitutes a valid prediction? • Date and time • Place of occurrence • Magnitude • Recorded in written form • Confidence estimate (probability) • Enough of the scientific basis for the prediction that its validity can be evaluated
  9. 9. • A prediction can be made, or not, and an earthquake may occur, or not; these basic possibilities are shown in the contingency table at right. Once the various outcomes are tabulated various performance measures can be calculated.E.g., the success rate is the proportion of all predictions which were successful [SR = a/(a+b)], while the Hit rate (or alarm rate) is the proportion of all events which were successfully predicted [H = a/(a+c)]. The false alarm ratio is the proportion of predictions which are false [FAR = b/(a+b)]. This is not to be confused with the false alarm rate, which is the proportion of all non-events incorrectly "alarmed" [F = b/(b+d)].
  10. 10. •Consequences of an false prediction • Predictions must also be reliable, as false alarms and cancelled alarms are not only economically costly, but seriously undermine confidence in, and thereby the effectiveness of, any kind of warning.
  11. 11. •Possible signals of an earthquake about to come • Laptops could be also used for the prediction of earthquakes
  12. 12. • Electrical disturbances in the Earth’s atmosphere
  13. 13. • Changes in Animal Behaviour
  14. 14. • Change in velocity of “S” &”P” waves
  15. 15. • Radon emissions

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