all of these have volcano or earthquake activity except
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Answer:
Chapter 2 focuses on Earthquakes and Volcanoes.
Lessons included in this chapter:
#4 Earthquakes - The Rolling Earth
#5 Volcanoes
#6 Volcanic Terms
Resources for Teachers can be found under the Chapter #2 Copymaster.
Select from the options on the right to proceed.
Earthquakes - The Rolling Earth Lesson #4
rollingearth1
An earthquake is a sudden, rapid shaking of the Earth caused by the release of energy stored in rocks. This energy can be built up and stored for many years and then released in seconds or minutes. Many earthquakes are so small that they can not be felt by humans. Some, on the other hand, have caused great destruction and have killed hundreds of thousands of people. The pink lines and dots on the map of the world above indicate the regions of earthquake activity.
There are two major regions of earthquake activity. One is the circum-Pacific belt which encircles the Pacific Ocean, and the other is the Alpide belt which slices through Europe and Asia. The circum-Pacific belt includes the West coasts of North America and South America, Japan, and the Phillipines.
Over one million earthquakes may occur each year on the Earth. Most earthquakes last only seconds, but some large quakes may last minutes. About 90% of all Earthquakes are produced at plate boundaries where two plates are colliding, spreading apart, or sliding past each other. When these plates move suddenly they release an incredible amount of energy that is changed into wave movement. Earthquake waves resemble sound and water waves in the manor in which they move. It is these waves that roll through the Earth's crust causing buildings to collapse, bridges to snap, mountains to rise, the ground to fall, and in some cases the ground to open up into huge cracks.
rollingearth2
Why do earthquakes occur? Scientists believed that the movement of the Earth's plates bends and squeezes the rocks at the edges of the plates. Sometimes this bending and squeezing puts great pressure on the rocks. Rocks are somewhat elastic, they can be bent without breaking. Have you ever stretched a rubberband? You know if you increase the tension too much though, the rubberband will snap!! Rock layers act somewhat the same way, if the pressures becomes too great the rock layer will break and move. When this occurs the layers will move along a crack in the Earth's crust called a fault or the release of energy will cause a new faultline to be produced. This rupture of the rocks and the resulting movement causes an earthquake.
rollingearth3
This is an aerial photo of the San Andreas fault line in California. The red arrows point to the crack in the crust that is the surface fault. This fault is the boundary between two huge plates, the North American plate and the Pacific plate. The two plates are sliding past each other in opposite directions. This type of plate boundary is called a transverse boundary. A transverse boundary is actually a tear in the Earth's crust. The black arrows represent the directions that the two plates are traveling.
This fault line is perhaps the most studied transverse boundary in the world. Many earthquakes each year occur on the San Andreas fault which runs in California from the Mexico border east of San Diego north to the San Francisco Bay area. The next photo shows the destruction that occurred during the 1971 San Fernando earthquake.
rollingearth4
This aerial photograph shows the destruction that occurred during the February 2, 1971 San Fernando earthquake. The freeway bridge and road were extensively damaged during this shaking of the crust.
AND MANY MORE.... IN HIGH STANDARD
All of these are volcanic or earthquake:
- Yellowstone earthquakes often occur in swarms they close together in time and space.
- This phenomenon is related to the transport of volcanic fluid near numerous small rock formations below the magma, a pattern that has been observed in volcanoes around the world.
- The largest eruption occurred in 1985, when more than 3,000 earthquakes occurred in three months on the northwest side of the park.
- Hundreds of earthquakes were recorded between locusts in 2009 (near Lake Village) and in 2010 (between Old Faithful and West Yellowstone).
- Yellowstone presents a dual threat to the community, including the threat of a major earthquake and an additional volcanic threat.
- Yellowstone suffered a major earthquake in the history of Intermountain West in the 1959 M W 7.3 Hebgen Lake earthquake.