1 earthquake, devastated, sumatra and caused a tsunami that impacted many countries near the indian ocean. In its aftermath, around 200 000 people were dead or missing, and there was over 10 billion dollars in damages. Welcome to today’s imagery adventure where we will explore you’ve guessed it earthquakes before we get started be sure to subscribe to my channel. So you will be the first to know when a new video comes out now let’s talk about earthquakes by the end of this video you’ll easily understand what earthquakes are why they happen and you’ll learn some really cool facts that you probably didn’t know about earthquakes. So let’s get started. What exactly is an earthquake? An earthquake is a sudden, violent shaking of the ground that can sometimes cause a lot of damage. Why in the world does this? Does the earth shake though let’s explore why this happens? The earth is made up of several different layers: the crust, which is solid, the mantle, which is viscous, meaning its consistency between a solid and a liquid, the outer and the inner core. The crust and the part of the mantle together form the lithosphere. The lithosphere is a really important concept to understand when it comes to earthquakes. The lithosphere is divided into many different pieces. Almost like a puzzle. These pieces are called plates. No, no, no, not the kind you used to eat, but these are called tectonic plates. These tectonics play shift or move around on top of the mantle.
So why does it matter that these plates are moving sometimes when the plates shift, they may move away from each other push up against each other, go under one another or slide past each other. When these plates slide past each other, they can create fractures called faults. You’Ve probably heard of a very famous one called the san andreas fault in california. Earthquakes happen along fault lines. We talked about how tectonic plates can move, but they can also stick with one another. While they’re moving too this movement and sticking can cause pressure, basically stress on the earth’s surface, sometimes a sudden movement of the plates can cause a release of the pent up stress with little to no warning which can cause an earthquake. The point at which the earthquake happens is called the hypocenter and the epicenter is directly above the earth’s surface. This is usually where the strongest part of the earthquake occurs, and what often we hear on the news when an earthquake happens there’s a lot of energy released. The energy travels in the form of waves, specifically seismic waves. These waves are important clue for scientists to understand when an earthquake is happening where it’s happening and to understand how strong it is, they use a special tool to measure the earthquakes by using seismometers. They look specifically at the magnitude wave to measure how much energy is released. There are many different skills that are used to measure. How strong an earthquake is.
One of the skills people are most familiar with is called the richter scale. Some sources, including the national geographic and the usgs, note that the richter scale is limited, inaccuracy because it doesn’t capture all the different seismic waves from an earthquake and the earthquake epicenter needs to be close to the seismograph. Many scientists instead use something called the moment. Magnitude skill as a way of measuring an earthquake’s magnitude, especially for really strong earthquakes, time to test your knowledge with a trivia question. According to the u.s geological survey, how many detectable earthquakes occur worldwide each year? Is it a five hundred thousand b, one hundred thousand c? Fifty thousand or d ten thousand – the answer is 500 000 a. Although 500 000 earthquakes are detected annually, we can only feel about 20 of them and only 100 cause damage. So what is an impact of an earthquake? It can cause damage and destroy roads, bridges and buildings. There can be a loss of life or injuries to people, because buildings and structures may collapse. Earthquakes can also trigger tsunamis. As we spoke at the beginning of the stem engineer. Video let’s check their knowledge with another quiz question: where was the largest recorded earthquake in the united states? Was it in a san francisco, california, three prince william, sound in alaska c, los angeles, california or d seattle? Washington? If you said, b, you’re correct the correct answer? Is the prince william sound in march 1964, a magnitude 9.
2 earthquake struck the prince williams sound and about 75 miles east of anchorage alaska according to history.com, it caused landslides and mass in a massive tsunami and one of the largest waves of that tsunami was over 200 Feet according to history.com, this quick, even changed the coastline of alaska and over 130 lives were lost. So now you know all about earthquakes, thanks for joining me in this image. Your adventure, if you like learning about some related topics, be sure to subscribe to the channel and follow stemij on instagram and twitter.