Post by SA Hunter on Apr 19, 2016 21:46:08 GMT 8
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There have been three deadly quakes in the past week alone. Two struck Japan's Kumamoto prefecture – a 6.2 magnitude earthquake last Thursday (April 14) and a 7.0 magnitude one on Saturday (April 16) – killing 41 people and injuring around 1,500 others. The third, a 7.8 magnitude earthquake, struck Ecuador on Sunday (April 17), killing at least 272 people and injuring more than 2,000 others.
So is the number of big earthquakes (defined as being more than 7.0 magnitude) on the rise? Yes, and it has been for some time. From 1979 to 1991, there were about 10 big earthquakes a year, science news website LiveScience reported. In 1992, that figure rose to 12.5. In 2010, it became 16.7 big earthquakes a year. Why is it going up? Most scientists think it's most likely random. Meaning it could have just as easily NOT been going up. In an interview with LiveScience, Mr Tom Parsons, a research geophysicist with the US Geological Survey (USGS), explained this by comparing the rise to the results of flipping a coin: It is possible to get the same side multiple times in a row even though the process is random.
Not quite convinced? Well, this isn't the first time there's been a rise in earthquakes. According to CityLab, a subsidiary of US magazine The Atlantic, there was also an increase in the number of quakes between 1950 and 1965. And in the grand scheme of things, this isn't anything out of the norm. USGS states on its website that according to records dating back to 1900, there are about 16 major earthquakes in any given year – 15 within the magnitude 7 range and one that's 8.0 or greater. From 1973 to 2011, a period of 38 years, there were only eight times that the number of big earthquakes exceeded this figure: 1976, 1990, 1995, 1999, 2007, 2009, 2010 and 2011. During that period, 2010 was the worst year, with 24 big earthquakes, while 1989 and 1988 saw only six and seven respectively.
Does the increase mean an earthquake of epic proportions is imminent? No. According to USGS, "a temporary increase or decrease in seismicity is part of the normal fluctuation of earthquake rates". "Neither an increase or decrease worldwide is a positive indication that a large earthquake is imminent." In fact, there are a lot more earthquakes happening than you probably know about. USGS estimates that there are several million earthquakes a year. Many go undetected as they happen at remote locations or have very small magnitudes. In the course of last week alone, 330 earthquakes of at least 2.5 magnitude were recorded by USGS, not including the two major ones in Japan and the 7.8 magnitude earthquake in Ecuador. Apart from the two that struck last week, there have been only three other earthquakes of magnitude 7.0 or greater this year: On March 2 in Sumatra, Indonesia, on Jan 30 in Yelizovo, Russia, and on Jan 24 in Old Iliamna, Alaska.
There have been three deadly quakes in the past week alone. Two struck Japan's Kumamoto prefecture – a 6.2 magnitude earthquake last Thursday (April 14) and a 7.0 magnitude one on Saturday (April 16) – killing 41 people and injuring around 1,500 others. The third, a 7.8 magnitude earthquake, struck Ecuador on Sunday (April 17), killing at least 272 people and injuring more than 2,000 others.
So is the number of big earthquakes (defined as being more than 7.0 magnitude) on the rise? Yes, and it has been for some time. From 1979 to 1991, there were about 10 big earthquakes a year, science news website LiveScience reported. In 1992, that figure rose to 12.5. In 2010, it became 16.7 big earthquakes a year. Why is it going up? Most scientists think it's most likely random. Meaning it could have just as easily NOT been going up. In an interview with LiveScience, Mr Tom Parsons, a research geophysicist with the US Geological Survey (USGS), explained this by comparing the rise to the results of flipping a coin: It is possible to get the same side multiple times in a row even though the process is random.
Not quite convinced? Well, this isn't the first time there's been a rise in earthquakes. According to CityLab, a subsidiary of US magazine The Atlantic, there was also an increase in the number of quakes between 1950 and 1965. And in the grand scheme of things, this isn't anything out of the norm. USGS states on its website that according to records dating back to 1900, there are about 16 major earthquakes in any given year – 15 within the magnitude 7 range and one that's 8.0 or greater. From 1973 to 2011, a period of 38 years, there were only eight times that the number of big earthquakes exceeded this figure: 1976, 1990, 1995, 1999, 2007, 2009, 2010 and 2011. During that period, 2010 was the worst year, with 24 big earthquakes, while 1989 and 1988 saw only six and seven respectively.
Does the increase mean an earthquake of epic proportions is imminent? No. According to USGS, "a temporary increase or decrease in seismicity is part of the normal fluctuation of earthquake rates". "Neither an increase or decrease worldwide is a positive indication that a large earthquake is imminent." In fact, there are a lot more earthquakes happening than you probably know about. USGS estimates that there are several million earthquakes a year. Many go undetected as they happen at remote locations or have very small magnitudes. In the course of last week alone, 330 earthquakes of at least 2.5 magnitude were recorded by USGS, not including the two major ones in Japan and the 7.8 magnitude earthquake in Ecuador. Apart from the two that struck last week, there have been only three other earthquakes of magnitude 7.0 or greater this year: On March 2 in Sumatra, Indonesia, on Jan 30 in Yelizovo, Russia, and on Jan 24 in Old Iliamna, Alaska.