Earthquake v Tsunamis
Q: How do earthquakes cause tsunamis?
Overview
This digital task card will explore how earthquakes can cause tsunamis. Firstly, you will learn how a tsunami is created by entering an interactive guide called the Anatomy of a tsunami, and then you will proceed to discover the various factors that determine the strength of a tsunami. When this is completed, you will witness the devastating effects a tsunami has on a country and it's people. In particular, the most recent catastrophic event in Japan 2011. Additionally, you will then learn how this catastrophic earthquake caused the tsunami in Japan. Finally, you will embark onto an online interactive simulation of a tsunami. This simulation enables you create a small pulse in the ocean to then observe how the wave gains amplitude as it approaches shore.
Background
Tsunamis are gigantic waves that come ashore with little or no warning. A tsunami is caused by earthquakes or volcanoes that move the land on the bottom of the ocean. Movement of the earth’s land is called an earth tremor. When a tremor shakes the land
under the sea, it causes the water at the surface to rise up in a hump. This high swell of water starts moving away. After a long trip, this swell finally reaches shore. It roars onto the beach as a wave.
under the sea, it causes the water at the surface to rise up in a hump. This high swell of water starts moving away. After a long trip, this swell finally reaches shore. It roars onto the beach as a wave.
Anatomy of a Tsunami
A tsunami is most often created by undersea earthquakes. See how the earth's crust comprises of massive tectonics plates that spread apart and collide, thus causing earthquakes and then tsunamis.
Click on the button below to enter an interactive guide to learn how a Tsunami is created. Upon entering the interactive guide, select Anatomy from the drop down box in What is a tsunami?
Click on the button below to enter an interactive guide to learn how a Tsunami is created. Upon entering the interactive guide, select Anatomy from the drop down box in What is a tsunami?
Tsunami's strength and intensity
The are multiple factors that influence tsunami's strength and intensity, such as Earthquake magnitude and depth of water at earthquake source.
Click on the button below to enter an interactive guide to learn more about the factors that influence the tsunami's strength and intensity. Once in the Interactive guide, select Effects from the drop down box in What is a tsunami?
Click on the button below to enter an interactive guide to learn more about the factors that influence the tsunami's strength and intensity. Once in the Interactive guide, select Effects from the drop down box in What is a tsunami?
Devastating effects of a Tsunami - Japan 2011
On Friday, March 11, 2011, Japan experienced a catastrophic earthquake. The earthquake occurred off the coast of the island of Honshu, approximately 129 km east of Sendai. The 9.0 Richter magnitude earthquake and the resulting tsunami have provoked the largest crisis that Japan has encountered since the end of World War II.
Steps to follow:
1) Click in video 1 below to witness the devastating effects a tsunami had on Japan in 2011.
2) Click video 2 below to then learn how this catastrophic earthquake event caused the tsunami in Japan.
Video 1 Video 2
Steps to follow:
1) Click in video 1 below to witness the devastating effects a tsunami had on Japan in 2011.
2) Click video 2 below to then learn how this catastrophic earthquake event caused the tsunami in Japan.
Video 1 Video 2
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When the 9.0 magnitude earthquake struck north eastern Japan, the destruction caused by the earthquake and aftershocks, related tsunamis devastated the Japanese coastline. Several nuclear power plants were damaged, leading to potentially serious health risks for tens of thousands of people.
Online interactive simulation of a tsunami
This interactive program simulates a tsunami from the initial wave pulse through to contact with a coastline. It shows very clearly how a tsunami, which may appear insignificant at the start, and then gains amplitude as it approaches shore, thus becoming one of nature's most destructive forces!
In the simulation, you may begin the wave pulse by clicking anywhere in the ocean on the left hand side of the screen. Students may also change the shape of the sea bottom near the coast and watch the effect on the approaching tsunami. The amplitude of the initial pulse is also adjustable by the student. To enter the simulation, click on the button below.
In the simulation, you may begin the wave pulse by clicking anywhere in the ocean on the left hand side of the screen. Students may also change the shape of the sea bottom near the coast and watch the effect on the approaching tsunami. The amplitude of the initial pulse is also adjustable by the student. To enter the simulation, click on the button below.
Questions???
1. What is a tsunami?
2. In your own words, explain how a tsunami is formed?
3. Which ocean are the most amount of tsunamis formed?
4. Apart from earthquakes, list 2 other factors that can cause a tsunami?
2. In your own words, explain how a tsunami is formed?
3. Which ocean are the most amount of tsunamis formed?
4. Apart from earthquakes, list 2 other factors that can cause a tsunami?
Interesting Facts:
- Tsunami means “Harbor wave” in Japanese (tsu – harbor, nami – wave).
- Tsunamis are huge waves of water that are most often caused by earthquakes, landslides or volcanic eruptions that occur either on land or at the bottom of the ocean.
- About 80% of all tsunamis occur in an area of the Pacific Ocean known as the ‘Ring of Fire’ which is a geological active area for tectonic shifts.
- A tsunami’s trough, the low point beneath the wave’s crest, often reaches shore first. When it does, it produces a vacuum effect that sucks coastal water seaward and exposes harbor and sea floors. This retreating of sea water is an important warning sign of a tsunami, because the wave’s crest and its enormous volume of water typically hit shore five minutes or so later.
- Tsunami waves can travel at speeds of 970km per hour, the speed of a jet plane.
- Tsunamis are huge waves of water that are most often caused by earthquakes, landslides or volcanic eruptions that occur either on land or at the bottom of the ocean.
- About 80% of all tsunamis occur in an area of the Pacific Ocean known as the ‘Ring of Fire’ which is a geological active area for tectonic shifts.
- A tsunami’s trough, the low point beneath the wave’s crest, often reaches shore first. When it does, it produces a vacuum effect that sucks coastal water seaward and exposes harbor and sea floors. This retreating of sea water is an important warning sign of a tsunami, because the wave’s crest and its enormous volume of water typically hit shore five minutes or so later.
- Tsunami waves can travel at speeds of 970km per hour, the speed of a jet plane.