How earthquakes happen pdf

Expect and prepare for potential aftershocks, landslides or even a tsunami if you live on a coast. Earthquakes occur most often along geologic faults, narrow zones where rock masses move in relation to one another. Alaska has more earthquakes than any other us state. Students write their own myth in the starter and then write to the tribe in the plenary to explain why earthquakes actually happen. No detected earthquakes have definitely been attributed to any of the specific mapped fault systems. During a geology lesson consider taking a day or two to study the science of earthquakes. Scientists cant tell that an earthquake is a foreshock until the larger. Chapter 12 earthquakes section 1 how and where earthquakes happen. Earthquakes can leave behind incredible devastation, while also creating some of the planets most magnificent formations. But this skin is not all in one piece it is made up of many pieces like a puzzle covering the surface of the earth. Based on the depth of their foci, earthquakes are classified into tree types. An earthquake also known as a quake, tremor or temblor is the shaking of the surface of the earth resulting from a sudden release of energy in the earth s lithosphere that creates seismic waves. Printable pdf of earthquakes booklet bgs earthquake british. This causes shock waves to shake the surface of the earth in the form of an earthquake.

In the offshore region to the west of vancouver island, more than 100 earthquakes of magnitude 5 or greater large enough to cause damage had they been closer to land have occurred during the past 70 years. The earth is made of an inner core, an outer core and a mantle, and the final layer is a thin crust covering the mantle, which. An earthquake is the vibration, sometimes violent, of the earths surface that follows a release of energy in the earths crust. An earthquake is what happens when two blocks of the earth suddenly slip past one another. Earthquakes happen when two large pieces of the earths crust suddenly slip. The shaking is caused by movements in earths outermost layer. Depending on the size of the mainshock, aftershocks can continue for weeks, months, and even years after the mainshock. The stress can cause the rock to slip and cause earthquakes.

Can cause major damage to poorly constructed buildings over small regions. These plates slowly move over a long period of time. These plates fit together like puzzle pieces but they. Today, earthquakes are often predicted as is the potential destruction they may cause. They have had about 12,000 earthquakes in the last 30. Earthquakes develop when tectonic plates, the massive jigsaw pieces that make up the crust of the earth, move suddenly, sending shockwaves through neighboring area. The surface where they slip is called the fault or fault plane. Fences across the san andreas fault ripped apart, and it was no longer clear who owned the land nearby. Earthquakes happen when these plates move under, slide past one another, or collide into one another. The tectonic plates are always slowly moving, but they get stuck at their edges due to friction. What is an earthquake and what causes them to happen. Faults or slipping zones the surfaces where these plates slip are termed as fault planes or faults, and the plate boundaries are made up of several such faults or slipping zones.

Each time you feel an aftershock, drop, cover and hold on. Damage is greatest from shallow earthquakes because the. Earthquake safety earthquake preparedness red cross. How does earthquake occur with explanation social science. How and where earthquakes happen continued where do earthquakes happen. When two blocks of rock or two plates are rubbing against each other, they stick a little. The risks that earthquakes pose to society, including death, injury, and economic loss, can be greatly reduced by 1 better planning, construction, and mitigation practices before earthquakes happen, and. Although louisiana lies in an area of low seismic risk, a number of historical earthquakes have occurred in our state. Earthquake science explained is a series of short articles for students, teachers, and parents originally published as weekly features in the san francisco chronicle. Rotating powerpoint with different myths and legends that explain why earthquakes happen. This sudden release of energy causes the seismic waves that make the ground shake.

These are smaller earthquakes that happen in the same place as the larger earthquake that follows. Most earthquakes occur along the edge of the oceanic and continental plates. Various societies have produced earthquake legends to explain these natural. Earthquakes are the result of plate tectonics, or shifting plates in the crust of earth, and quakes occur when the frictional stress of gliding plate boundaries builds and causes failure at a. Task 2 using the worksheet below, explain with the aid of a diagram how earthquakes happen. Learn about the geophysics behind earthquakes, how they are measured, and where the most powerful earthquake ever witnessed occurred. May 12, 2020 an earthquake is an intense shaking of earths surface. How earthquakes happen if you would like a printable, nonanimated version of this graphic, click on the following link to open a pdf file and then follow the icon to print that file. The crust and the top of the mantle make up a thin skin on the surface of our planet.

The movement of earths crust resulting from the release of built up potential energy between two stuck tectonic plates. The earths crust the outer layer of the planet is made up of several pieces, called plates. The pacific coast is the most earthquakeprone region of canada. The nature and cause of earthquakes kitp online talks. Most of the deaths are when people are trapped in falling buildings.

Learn more about the causes and effects of earthquakes in this article. Earthquakes are measured using instruments called seismometers that detect the vibrations caused by seismic waves as they travel through the crust. Earthquake magnitude earthquake severity richter magnitude earthquake effects less than 3. Geological survey general information product presents some of the new understanding gained and sci. Tectonic plates are what make up the earths crust, its outermost layer. Earthquakes occur all the time all over the world, both along plate edges and along faults. Earthquake science explained is a series of short articles for students, teachers, and parents. You should aim to use the following words in your description. Seismic waves can be both natural from earthquakes or caused by human activity explosions. An earthquake is caused by a sudden slip on a fault. Earthquakes are usually caused when rock underground suddenly breaks along a fault. An aerial view of the san andreas fault in the carrizo plain, central california.

Check yourself for injuries and get first aid, if necessary, before helping injured or trapped persons. Most earthquakes happen near the boundaries between plates. Earthquakes can range in size from those that are so weak that they cannot be felt to those violent enough to propel objects and people into the. Earthquakes happen deep underground along tectonic plate boundaries. Although the earth looks like a pretty solid place from the surface, its actually extremely active just below the surface. Earthquakes usually occur on the edges of large sections of the earths crust called tectonic plates. Jun 01, 2009 how earthquakes happen if you would like a printable, nonanimated version of this graphic, click on the following link to open a pdf file and then follow the icon to print that file.

They have tended to be of low magnitude and occur with low frequency. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Therefore, earthquakes are most frequent along the edges of the tectonic plates where one plate is moving relative to the adjoining plate. When the stress on the edge overcomes the friction, there is an earthquake that releases energy in waves that travel through the earths crust and cause the shaking that we feel in california there are two plates the pacific plate and the. Earthquakes teacher notes and student activities ga record. When large earthquakes occur in such areas the results can be catastrophic, with terrible loss of human lives and untold economic cost. Discuss why they happen and how scientists measure and predict them. Additionally, if an earthquake occurs in a distant place especially if the hypocenter is shallow large and slow swaying can occur after the ground. The usgs earthquake hazards program is part of the national earthquake hazards reduction program nehrp, established by congress in 1977, and the usgs advanced national seismic system anss was established by congress as a nehrp facility. Mar 24, 2020 earthquake, any sudden shaking of the ground caused by the passage of seismic waves through earths rocks.