Earthquakes, also called temblors, can be so tremendously destructive, it’s hard to imagine they occur by the thousands every day around the world, usually in the form of small tremors. WHERE DO MOST EARTHQUAKES OCCUR? Some 80 percent of all the planet's earthquakes occur along the rim of the Pacific Ocean, called the "Ring of Fire" because of the preponderance of volcanic activity there as well. Most earthquakes occur at fault zones, where tectonic plates—giant rock slabs that make up the Earth's upper layer—collide or slide against each other. These impacts are usually gradual and unnoticeable on the surface; however, immense stress can build up between plates. When this stress is released quickly, it sends massive vibrations, called seismic waves, often hundreds of miles through the rock and up to the surface. Other quakes can occur far from faults zones when plates are stretched or squeezed. EARTHQUAKE MAGNITUDE RATINGS AND THEIR IMPACTS Scientists assign a magnitude rating to earthquakes based on the strength and duration of their seismic waves. A quake measuring 3 to 5 is considered minor or light; 5 to 7 is moderate to strong; 7 to 8 is major; and 8 or more is great. On average, a magnitude 8 quake strikes somewhere every year and some 10,000 people die in earthquakes annually. Collapsing buildings claim by far the majority of lives, but the destruction is often compounded by mud slides, fires, floods, or tsunamis. Smaller temblors that usually occur in the days following a large earthquake can complicate rescue efforts and cause further death and destruction. Loss of life can be avoided through emergency planning, education, and the construction of buildings that sway rather than break under the stress of an earthquake. Earthquake Safety TipsEarthquakes are a common occurrence, rumbling below Earth's surface thousands of times every day. But major earthquakes are less common. Here are some things to do to prepare for an earthquake and what to doonce the ground starts shaking. SAFETY TIPS• Have an earthquake readiness plan. • Consult a professional to learn how to make your home sturdier, such as bolting bookcases to wall studs, installing strong latches on cupboards, and strapping the water heater to wall studs. • Locate a place in each room of the house that you can go to in case of an earthquake. It should be a spot where nothing is likely to fall on you, like a doorframe. • Keep a supply of canned food, an up-to-date first aid kit, 3 gallons (11.4 liters) of water per person, dust masks and goggles, and a working battery-operated radio and flashlights in an accessible place. • Know how to turn off your gas and water mains. IF SHAKING BEGINS• Drop down; take cover under a desk or table and hold on. • Stay indoors until the shaking stops and you're sure it's safe to exit. • Stay away from bookcases or furniture that can fall on you. • Stay away from windows. In a high-rise building, expect the fire alarms and sprinklers to go off during a quake. • If you are in bed, hold on and stay there, protecting your head with a pillow. • If you are outdoors, find a clear spot away from buildings, trees, and power lines. Drop to the ground. • If you are in a car, slow down and drive to a clear place. Stay in the car until the shaking stops. Comments are closed.
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Erik E. Mason
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