Table of Contents
What happens when a fault moves suddenly?
Sudden motions along faults cause rocks to break and move suddenly, releasing the stored up stress energy to create an earthquake. A slip is the distance rocks move along a fault and can be up or down the fault plane.
Where do most movement happen in the earth’s crust?
Most movement occurs along narrow zones between plates, plate boundaries, where the results of plate-tectonic forces are most evident. Atlantic ocean, along a global system of mountain ridges, Earth’s plates are growing and spreading apart.
Is the sudden movement of earth crust at a fault line?
An earthquake is the sudden movement of Earth’s crust. Earthquakes occur along fault lines, cracks in Earth’s crust where tectonic plates meet.
How does the Earth’s crust move during an earthquake?
Finally, when the plate has moved far enough, the edges unstick on one of the faults and there is an earthquake. The tectonic plates divide the Earth’s crust into distinct “plates” that are always slowly moving. Earthquakes are concentrated along these plate boundaries.
When do blocks of rock move, they are called faults?
If the blocks of rock on one or both sides of a fracture move, the fracture is called a fault (figure 11). Sudden motions along faults cause rocks to break and move suddenly. The energy released is an earthquake.
How does the size of the fault affect the magnitude of an earthquake?
The length of the wiggle depends on the size of the fault, and the size of the wiggle depends on the amount of slip. The size of the earthquake is called its magnitude. There is one magnitude for each earthquake. Scientists also talk about the intensity of shaking from an earthquake, and this varies depending on where you are during the earthquake.
Why do rocks break at the surface of the Earth?
At the Earth’s surface, rocks usually break quite quickly, but deeper in the crust, where temperatures and pressures are higher, rocks are more likely to deform plastically. Sudden stress, such as a hit with a hammer, is more likely to make a rock break. Stress applied over time often leads to plastic deformation.