Tuesday, 16 March 2010
Ring of Fire
My job allows me to wallow in natural disasters. Earthquakes, volcanoes, tsunamis, tornadoes they have always oddly intrigued me. Seismic shifts below the earth's surface resulting in small tremors happen all the time, the ground often moves in our house according to the other half....
On a serious note an earthquake shook Los Angeles early today, it was only a 4.4 magnitude, and fortunately there was no sign of any significant damage or injury but this was one of over 700 quakes in that region during the past week.
Californian's live with the threat of earthquakes every time they walk across the cracks in the pavement. Friends of mine in San Francisco have dedicated family disaster plans ready to put into action when the 'Big One' happens. Slightly more reassuring at home we have a smoke detector and window locks to prevent 'disaster.'
Researchers have calculated a 70% probability that southern California will be hit by a large earthquake in the next 30 years. The forecast is based on the frequency of past events but predicting earthquakes is notoriously difficult. Forecasts tend to be very general, specifying a range of decades rather than years or weeks for possible activity but the only thing that is certain is that it will happen.
Earthquakes are produced when the earth’s tectonic plates shift against or collide with each other and recent activity in Haiti, Chile, Japan's Ryuku island, Taiwan, Indonesia and eastern Turkey have made me look a bit closer at the huge horseshoe shaped oceanic trench that encircles the Pacific Ocean and 90% of the world's earthquakes occur along what is unabashedly called the Ring of Fire.
The Ring of Fire is a 40,000km (25,000-mile) long zone where tectonic plates rub up against each other in the unlimited expanse of the Pacific Ocean. The area is named for its many active volcanoes but it is also the most seismically active zone on Earth.
After the Chilean quake the immediate focus was on the threat of tsunami, a powerful wave that travels from the epicenter of the quake across the ocean basin, and because Chile's quake occurred offshore, when the underwater plates shake, they push the water up above them, creating the beginning of a wave, not unlike dropping a stone in a bathtub, waves incidentially that travel at roughly the speed of a passenger jet!
The Chilean quake, which was so powerful it actually moved cities and shortened the day, occurred six weeks after the catastrophic tragedy in Haiti, which asked the question whether we are entering a new era of seismological disasters? But the two quakes were unrelated, as was the one in LA today, occurring each on different fault lines.
Despite scientists having a huge amount of knowledge of the earth's fault lines, the only thing that is vaguely predictable is that the next earthquake will almost certainly take place within the Ring of Fire's boundaries of interconnecting fault lines under the sea. Unfortunately prediciting where the epicenter and subsequent fallout will be is beyond mere science. ¶ 22:04
My job allows me to wallow in natural disasters. Earthquakes, volcanoes, tsunamis, tornadoes they have always oddly intrigued me. Seismic shifts below the earth's surface resulting in small tremors happen all the time, the ground often moves in our house according to the other half....On a serious note an earthquake shook Los Angeles early today, it was only a 4.4 magnitude, and fortunately there was no sign of any significant damage or injury but this was one of over 700 quakes in that region during the past week.
Californian's live with the threat of earthquakes every time they walk across the cracks in the pavement. Friends of mine in San Francisco have dedicated family disaster plans ready to put into action when the 'Big One' happens. Slightly more reassuring at home we have a smoke detector and window locks to prevent 'disaster.'
Researchers have calculated a 70% probability that southern California will be hit by a large earthquake in the next 30 years. The forecast is based on the frequency of past events but predicting earthquakes is notoriously difficult. Forecasts tend to be very general, specifying a range of decades rather than years or weeks for possible activity but the only thing that is certain is that it will happen.
Earthquakes are produced when the earth’s tectonic plates shift against or collide with each other and recent activity in Haiti, Chile, Japan's Ryuku island, Taiwan, Indonesia and eastern Turkey have made me look a bit closer at the huge horseshoe shaped oceanic trench that encircles the Pacific Ocean and 90% of the world's earthquakes occur along what is unabashedly called the Ring of Fire.
The Ring of Fire is a 40,000km (25,000-mile) long zone where tectonic plates rub up against each other in the unlimited expanse of the Pacific Ocean. The area is named for its many active volcanoes but it is also the most seismically active zone on Earth.
After the Chilean quake the immediate focus was on the threat of tsunami, a powerful wave that travels from the epicenter of the quake across the ocean basin, and because Chile's quake occurred offshore, when the underwater plates shake, they push the water up above them, creating the beginning of a wave, not unlike dropping a stone in a bathtub, waves incidentially that travel at roughly the speed of a passenger jet!
The Chilean quake, which was so powerful it actually moved cities and shortened the day, occurred six weeks after the catastrophic tragedy in Haiti, which asked the question whether we are entering a new era of seismological disasters? But the two quakes were unrelated, as was the one in LA today, occurring each on different fault lines.
Despite scientists having a huge amount of knowledge of the earth's fault lines, the only thing that is vaguely predictable is that the next earthquake will almost certainly take place within the Ring of Fire's boundaries of interconnecting fault lines under the sea. Unfortunately prediciting where the epicenter and subsequent fallout will be is beyond mere science. ¶ 22:04
