welcome to our earthquakes page!
on this page you will learn about the forces in earth's crust, earthquakes and seismic waves, monitoring earthquakes, and earthquake safety.
Forces in earth's crust
Normal faults
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Reverse fault
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Strike-slip fault
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Earthquakes and seismic waves
Seismic Waves Animation ~ Raelynn |
Different Scales slide show ~Samantha |
Mercali Scale -JenMercali Scale is a scale that developed to rate earthquakes according to the level of damage at a given place. One earthquake can have different Mercali ratings if it causes different amounts of ground motion at different locations.
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Richter Scale -JenA Richter Scale is a rating of an earthquake's magnitude based on the size of its seismic waves. Seismic waves are measured by a seismograph. It provides accurate measurements ONLY for small earthquakes that are nearby.
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moment magnitude scale -JenMoment Magnitude Scale estimates total energy released by earthquakes. It rates earthquakes of all sizes, near or far. Today, geologists have been using this more than the Richter Scale.
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How to find the epicenter animation
By Cassidy and Taryn
Geologists use seismic waves to locate an earthquake epicenter. P waves arrive at a seismograph first, with S waves following behind. Scientists measure the difference between the arrival times of the P and S waves. The farther away the earthquake is, the greater the time between the arrival of P and S waves. Then, they draw at least three circles using data from different seismographs all over the world. The center of each circle is the seismograph’s location, while the radius is the distance from that seismograph to the epicenter. The point where the three circles intersect is the location of the epicenter.
Paragraph ~ Taryn
Paragraph ~ Taryn
earthquake safety
SAFETY - SOMETHING THAT NOT ALL OF US MAY BE ABLE TO AFFORD ~ WRITTEN BY: KIANA
Monitoring Earthquakes
how do geologists monitor faults?
HOW ARE SEISMOGRAPHIC DATA USED?
By: Krista
Seismographic data is used in three different ways: mapping faults, detecting changes along faults, and trying to predict earthquakes. Mapping faults can be hard because most faults are hidden under a layer of deep soil or rock. To find faults that are hidden under soil or rock, they use seismographs. Seismographs detect the seismic waves that reflect off of faults and record its findings. By knowing this geologists then know where and how deep the fault is. Finding the locations of hidden faults help scientists figure out where there are greater risks of an earthquake. The size of an earthquake is determined by the amount of friction there is. Friction is the force that resists the movement of one surface as it move across another. Friction happens because all surfaces are not smooth. Their can be different levels of friction low, moderate, and high. Low friction causes the rocks of a fault to pass each other almost smoothly so that their will not be and big earthquakes. Moderate friction causes the fault sides to smash together and jerk free from time to time. This will create a small earthquake. High friction will latch the rocks of the fault together causing a lot of stress, creating a large earthquake. Scientist still can not predict when an earthquake will exactly occur even with reliable resources. Stress along a fault will normally create and earthquake, but some times and earthquake will fail to occur. Sometimes more than one earthquake can relieve stress along a fault. This is why scientist still can’t determine when exactly an earthquake will occur.ye
How Earthquakes Affect Our Lives
New Zealand Earthquake
BY: TAYLOR Y.
Earthquakes affect our lives because it causes us to lose our houses, money, jobs, loved ones, and many more. Earthquakes can cause cracks in the ground, fires, and buildings to fall over or break apart. The earthquake in New Zealand happened on September 4, 2010. The magnitude of this earthquake was 7.0 using the Richter scale. There was an aftershock of 5.7 magnitude, 20 minutes later.
To learn more about the New Zealand earthquake, on the left is a video of the damage it caused. On the right is a map of where the location of the earthquake was.
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