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Any earthquake facts?

my son has to do a report on earthquakes and i can not find any information in kid language (too many big words) he needs to know

What causes earthquakes?

what is an earthquake?

how do earth quakes affect the earth?

when an earthquake can happen?

4 Answers

  • Anonymous
    1 decade ago
    Favorite Answer

    Earthquakes are usually caused when rock underground suddenly breaks along a fault. This sudden release of energy causes the seismic waves that make the ground shake. When two blocks of rock or two plates are rubbing against each other, they stick a little. They don't just slide smoothly; the rocks catch on each other. The rocks are still pushing against each other, but not moving. After a while, the rocks break because of all the pressure that's built up. When the rocks break, the earthquake occurs. During the earthquake and afterward, the plates or blocks of rock start moving, and they continue to move until they get stuck again. The spot underground where the rock breaks is called the focus of the earthquake. The place right above the focus (on top of the ground) is called the epicenter of the earthquake.

    1.The largest recorded earthquake in the United States was a magnitude 9.2 that struck Prince William Sound, Alaska on Good Friday, March 28, 1964 UTC.

    2.The largest recorded earthquake in the world was a magnitude 9.5 (Mw) in Chile on May 22, 1960.

    3.The earliest reported earthquake in California was felt in 1769 by the exploring expedition of Gaspar de Portola while the group was camping about 48 kilometers (30 miles) southeast of Los Angeles.

    4.Before electronics allowed recordings of large earthquakes, scientists built large spring-pendulum seismometers in an attempt to record the long-period motion produced by such quakes. The largest one weighed about 15 tons. There is a medium-sized one three stories high in Mexico City that is still in operation.

    5.The average rate of motion across the San Andreas Fault Zone during the past 3 million years is 56 mm/yr (2 in/yr). This is about the same rate at which your fingernails grow. Assuming this rate continues, scientists project that Los Angeles and San Francisco will be adjacent to one another in approximately 15 million years.

    6.The East African Rift System is a 50-60 km (31-37 miles) wide zone of active volcanics and faulting that extends north-south in eastern Africa for more than 3000 km (1864 miles) from Ethiopia in the north to Zambezi in the south. It is a rare example of an active continental rift zone, where a continental plate is attempting to split into two plates which are moving away from one another.

    7.The first "pendulum seismoscope" to measure the shaking of the ground during an earthquake was developed in 1751, and it wasn't until 1855 that faults were recognized as the source of earthquakes.

    8.Moonquakes ("earthquakes" on the moon) do occur, but they happen less frequently and have smaller magnitudes than earthquakes on the Earth. It appears they are related to the tidal stresses associated with the varying distance between the Earth and Moon. They also occur at great depth, about halfway between the surface and the center of the moon.

    9.Although both are sea waves, a tsunami and a tidal wave are two different unrelated phenomenona. A tidal wave is a shallow water wave caused by the gravitational interactions between the Sun, Moon, and Earth. A tsunami is a sea wave caused by an underwater earthquake or landslide (usually triggered by an earthquake) displacing the ocean water.

    10.The hypocenter of an earthquake is the location beneath the earth's surface where the rupture of the fault begins. The epicenter of an earthquake is the location directly above the hypocenter on the surface of the earth.

    11.The greatest mountain range is the Mid-Ocean Ridge, extending 64,374 km (40,000 mi) from the Arctic Ocean to the Atlantic Ocean, around Africa, Asia, and Australia, and under the Pacific Ocean to the west coast of North America. It has a greatest height of 4207 m (13,800 ft) above the base ocean depth.

    12.The world's greatest land mountain range is the Himalaya-Karakoram. It countains 96 of the world's 109 peaks of over 7317 m (24,000 ft). The longest range is the Andes of South America which is 7564 km (4700 mi) in length. Both were created bythe movement of tectonic plates.

    13.It is estimated that there are 500,000 detectable earthquakes in the world each year. 100,000 of those can be felt, and 100 of them cause damage.

    14.It is thought that more damage was done by the resulting fire after the 1906 San Francisco earthquake than by the earthquake itself.

    15.A seiche (pronounced SAYSH) is what happens in the swimming pools of Californians during and after an earthquake. It is "an internal wave oscillating in a body of water" or, in other words, it is the sloshing of the water in your swimming pool, or any body of water, caused by the ground shaking in an earthquake. It may continue for a few moments or hours, long after the generating force is gone. A seiche can also be caused by wind or tides.

    16.Each year the southern California area has about 10,000 earthquakes. Most of them are so small that they are not felt. Only several hundred are greater than magnitude 3.0, and only about 1

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  • 1 decade ago

    1) There are two main reasons as to why an earthquake happens. One reason is when a volcano erupts. Another reason is a disturbance in the movement of plates beneath the Earth's crust.

    2) Earthquakes are the shaking, rolling or sudden shock of the earth's surface. They are Earth's natural means of releasing stress. Earthquakes cannot be predicted - although scientists are working on it.

    3) Earthquakes affect society greatly. They can cause death and massive damage.

    4) Scientists are not quite exactly sure and have not yet determined a method to detect when earthquakes occur, because earthquakes are unpredictable.

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  • Anonymous
    6 years ago

    There are many facts about earthquakes an earthquake can rip open the earths crust then form mountains then the mountains form into volcano. how to survive a earthquake there are many ways to survive a earthquake you have to find a deap hole not that deap then thay you head down then you will be safe.

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  • 4 years ago

    BBC site has plenty of info.

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