China has suffered some terrible earthquakes, and it isn’t surprising that China’s scientists want to find ways of forecasting them. In 1975, they were successful. They cleared the city of Haicheng two hours before a devastating quake and saved the city’s population. Earthquake forecasting is, however, still inexact; the Chinese have failed to predict several earthquakes since 1975, but they have advanced the science of earthquake prediction.
We now know that small tremors (foreshocks) often occur before a larger movement. Changes also occur in the electric and magnetic properties of rocks, and growing tension often causes swellings and cracks in the ground. When rocks cracks, a radioactive gas, radon, is often released. Radon dissolves in water and so, if the radon content in well water builds up, an earthquake may be on the way.
Chinese workers have also been asked to report strange behaviour by animals. Before quakes, dog may howl, nervous animals run from buildings and fish thrash about in water. Perhaps they sense changes which we can not detect.
Can you predict earthquakes? How can we foretell Earthquake?
No scientists have ever predicted a major earthquake. We do not know how, and we do not expect to know how any time in the foreseeable future. Scientists can only calculate the probability that a significant earthquake will occur in a specific area within a certain number of years.
An earthquake prediction must define 3 elements: 1) the date and time, 2) the location, and 3) the magnitude.
Yes, some people say they can predict earthquakes, but here are the reasons why their statements are false:
- They are not based on scientific evidence, and earthquakes are part of a scientific process. For example, earthquakes have nothing to do with clouds, bodily aches and pains, or slugs.
- They do not define all three of the elements required for a prediction.
- Their predictions are so general that there will always be an earthquake that fits; such as,
(a) There will be a M4 earthquake somewhere in the U.S. in the next 30 days.
(b) There will be a M2 earthquake on the west coast of the U.S. today.
If an earthquake happens to occur that remotely fits their prediction, they claim success even though one or more of their predicted elements is wildly different from what actually occurred, so it is therefore a failed prediction.
Predictions (by non-scientists) usually start swirling around social media when something happens that is thought to be a precursor to an earthquake in the near future. The so-called precursor is often a swarm of small earthquakes, increasing amounts of radon in local water, unusual behavior of animals, increasing size of magnitudes in moderate size events, or a moderate-magnitude event rare enough to suggest that it might be a foreshock.