Beyond Tsunamis: 6 Other Fascinating Effects of Earthquakes
Earthquakes themselves aren’t dangerous—it’s what happens after that we have to worry about. The whole world watched the tsunami disaster unfold in Japan, and were glued to their TV sets as aid groups did their best to help via donations, e-health and volunteers. But what about the lesser-known effects of earthquakes? The ones you might not hear about?
Landslides
Earthquakes are one of the main causes of landslides around the world. This particular landslide, a result of the Great Sichuan Earthquake that happened on May 12, 2008, along with other landslides in the area, accounted for many of the earthquake’s casualties. Official stats confirm 69,197 dead, 374,176 injured and 18,344 missing. The landslides also blocked rivers and caused extensive flooding.
Fires
Earthquake fires are caused by a variety of things, from broken power and gas lines to overturned wood or coal stoves. And if the water lines are broken too, well, that makes things even worse.
This famous photo, taken by Arnold Genthe in San Francisco, California on the morning of April 18, 1906, depicts the aftermath of the devstating earthquake. The quake spawned fires that destroyed about 28,000 buildings and 500 blocks—1/4 of San Francisco.
Liquefaction
Liquefaction happens when groundwater mixes with sand or soil during a moderate or strong earthquake. This causes the water-saturated sediment to lose strength and behave like a quicksand-y liquid. The result? Check out this video taken just after the 2011 Japan earthquake.
Sand Volcanoes
Sand volcanoes, also known as sand boils or sand blows, occur in areas of liquefaction. As geologist Mark Quigley said in an interview with New Zealand’s ONE News, “The water is basically squeezed out of the pore spaces with the shaking, and sort of busts through up onto the surface and carries sand and mud with it.” Expensive and messy.
Surface Faulting
These rows of lettuce were offset by the 6.9M earthquake that happened on October 15, 1917 in El Centro, California. It happened because the fault was of the “right lateral strike-slip” variety, which means one side of the fault moved horizontally to the right, with respect to the other side.
Changes in the Earth's Rotation
According to NASA, the 2011 Japan earthquake may changed the distribution of the Earth’s mass. That should have sped up the Earth’s rotation, shortening each day by about 1.8 microseconds, and shifted the position of the Earth’s figure axis. But that’s nothing to worry about, NASA said. Apparently the Earth’s rotation changes all the time. No big deal.