Thursday, November 18, 2010

Guest Post - The 5 Largest Earthquakes Ever Recorded

So I was contacted a little while ago by someone wanting to write a guest blog post that would fall in line with the essence that is the Geoscience Education angle that the blog goes for. So I agreed after I heard her idea and this is what we have today, our first guest post from a fellow blogger in her own right, Alvina Lopez.


The rigid crust of the Earth and the tectonic forces that stress them can cause some seriously powerful seismic waves, which in turn result in what we know as earthquakes. Though earthquakes may seem like a rare occurrence for those who do not live in earthquake-prone areas like Alaska and California, they are actually more common than you may think. In fact, more than one million earthquakes occur every year, though the majority of them are imperceptible beneath our feet, according to the Center for Earthquake Research and Information at the University of Memphis (CERI). But while most earthquakes barely register at all on seismometers, once in a while, the planet will dole one out that crumbles buildings and splits the Earth as if it were torn at the seams. These are the 5 worst earthquakes ever recorded.

1. The Great Chilean Earthquake of 1960. On May 22, a regular mid-afternoon day was abruptly halted by a 9.5 magnitude earthquake that ripped across the country. More than 2,000 people were killed and 3,000 were injured. A second earthquake shook the area before help could even be mobilized for those affected by the first quake, according to the U.S. Geological Survey. This particular quake also triggered landslides in the Andes, tsunamis off the coasts of Chile, Hawaii, Japan, the Philippines, New Zealand, Australia, and the Aleutian Islands, as well as the volcanic eruption of Cordon Caulle in the Andes. In addition to this, seismographs recorded that the seismic waves from the quake continued to rattle the entire planet for days due to the free oscillation effect.

2. The Sumatra-Andaman Earthquake of 2004. The day after Christmas, an undersea quake off the coast of Sumatra, Indonesia was recorded on the seismograph, registering at a magnitude of somewhere around 9.1 and 9.3. Approximately 230,000 people lost their lives due to the quake and the devastating tsunamis it caused, which swamped Indonesia, Sri Lanka, Thailand, and India. The resulting tsunamis from this quake were responsible for thousands of deaths as the waters flooded towns or wiped them away altogether. Like in the Great Chilean Earthquake of 1960, seismometers also recorded that the planet shuddered for days after the initial earthquake struck.

3. The Great Alaskan Earthquake of 1964. On the evening of March 28, the ground began to rumble and buildings started to shudder, then collapse in Prince William Sound, Alaska. Registering at a magnitude of 9.2, this particular earthquake is in the record books as the largest recorded quake to hit the United States. That night, more than 115 died due to the earthquake and the tsunamis it generated off the coasts of Alaska, Oregon, and California. The earthquake itself was felt for an astonishing 7 minutes. The ground split and ruptured, causing some surfaces to be lowered as much as 17 meters, according to the CERI, and most of the damage fell on the city of Anchorage.

4. The Kamchatka Earthquake of 1952. The Kamchatka area, which is a peninsula in Russia, is no stranger to powerful earthquakes. In 1737, a magnitude 8.3 earthquake was recorded, and in 1923, a magnitude 8.5 earthquake was recorded. However, it was in 1952 when the most powerful earthquake struck the area, registering as a 9.0 magnitude quake. Tsunamis arose from the quakes, causing expensive property damage and causing several deaths, though no official death toll figures have been reported. The quake triggered tsunamis off the coast of Japan, Hawaii, Alaska, Chile, and New Zealand, though luckily with no reported deaths.

5. The Arica Earthquake of 1868. Arica, Peru (now Chile) experienced a terrifying 9.0 magnitude earthquake on August 13. Between the Nazca Plate and South American Plate, the quake sent buildings toppling and the subsequent tsunami ripped anchored ships from the docks. Coastal towns were completely decimated, or came close to it as huge tsunami waves crashed into and flooded the streets. Hundreds of aftershocks, with about 400 recorded, were felt until about August 25, a little under two weeks after the initial quake struck. Approximately 25,000 casualties were reported due to the quake itself and the tsunamis it triggered.

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This guest post is contributed by Alvina Lopez, who writes on the topics of accredited online schools.  She welcomes your comments at her email Id: alvina.lopez


  1. Interesting article. It strikes me that in every case its the tsunami that caused most of the deaths. Are tsunami's ALWAYs associated with major earthquakes?

  2. Not ALWAYS. It depends on the magnitude (amount of energy released), location (it has to be beneath the ocean floor), and depth (the deeper it is the more energy will dissipate before it reaches the Earth's surface). A lot of the deadlier ones are associated with tsunamis because those have a tendancy to cause more deaths than the straight earthquakes but they are not always linked.

  3. Case in point:

    There was a series of 4 earthquakes in 2 days, 3 of which were greater than a 7 but they were all over 600 km in depth. So even though they were large enough and under the ocean they were too deep to cause any damage and/or a tsunami.

  4. I am struck by the contrast of number of reported deaths from each, ranging from zero to Oh, wow, that is a lot of people. Most of that difference will be the number of people who live in the area of the quake and in the areas where quake-generated tsunamis strike ground. The rest will be differences in the type of construction is used in the areas. Some buildings are simply more dangerous than others when shaking starts. I hope that in the centuries going forward people choose to build only "earthquake-proof" buildings, so that, over time, the number of deaths from huge quakes, even in heavily populated regions, goes down.

  5. Sometimes that is not even enough. If you think of the Haiti earthquake, it was not very large but it was in an area that was very poor (not able to afford earthquake proof buildings) but also in an area that did not get many earthquakes. So why would they even bother to build earthquake proof if they felt that it was superfluous?

  6. In 2011, there was among fifth largest earthquake that occurred in Japan. The earthquake generated tsunami that made the lives losses toll peaked. During previous natural disaster event, earthquake happened in not so prepared nations. However, Japan was advanced country with earthquake and tsunami warning. They still had lost more than 10.000 lives. What is your opinion? Read about where and why earthquakes occur


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