Predicting Earthquakes
Today's scientists understand earthquakes a lot better than we did even 50 years ago, but they still can't match the quake-predicting prowess of the common toad (Bufo bufo), which can detect seismic activity days in advance of a quake. A 2010 study published in Journal of Zoology found that 96 percent of male toads in a population abandoned their breeding site five days before the earthquake that struck L'Aquila, Italy, in 2009, about 46 miles (74 kilometers) away. Researchers aren't quite sure how the toads do this, but it's believed that they can detect subtle signs, such as the release of gases and charged particles, that may occur before a quake [source: Science Daily]. Scientists can predict where major earthquakes are likely to occur, however, based on the movement of the plates in the Earth and the location of fault zones. They also can make general guesses about when earthquakes might occur in a certain area, by looking at the history of earthquakes in the region and detecting where pressure is building along fault lines. For example, if a region has experienced four magnitude 7 or larger quakes during the past 200 years, scientists would calculate the probability of another magnitude 7 quake occurring in the next 50 years at 50 percent. But these predictions may not turn out to be reliable because, when strain is released along one part of a fault system, it may actually increase strain on another part [source: USGS].
۰۶ خرداد ۹۵ ، ۲۳:۵۹