What is an earthquake?
Make a video for young learners. Easy to understand
视频信息
答案文本
视频字幕
Our Earth is made of different layers, just like an onion! The outside layer where we live is called the crust. It's like a hard shell that covers the whole Earth. Under the crust are more layers - the mantle and the core. The crust is very thin compared to the whole Earth, but it's where all life exists!
The Earth's crust is not one solid piece. It's broken into giant puzzle pieces called tectonic plates! These plates are huge - some are as big as entire continents! They float on the hot, soft rock below and move very, very slowly. Some move towards each other, some move away, and some slide past each other. It's like a giant, slow-motion puzzle that never stops moving!
Sometimes these giant puzzle pieces get stuck! When they try to move but can't, they start pushing against each other harder and harder. It's like trying to push two heavy boxes that are stuck together. The pressure builds up more and more. The rocks get squeezed and twisted. All this pressure has to go somewhere, and it's building up energy that wants to be released!
Finally, the pressure becomes too much and the stuck pieces suddenly break free! When this happens, all that built-up energy is released at once. The ground shakes and moves - this is an earthquake! The shaking energy travels out in waves, like ripples in a pond when you drop a stone. The waves spread out in all directions from where the pieces broke apart!
When an earthquake happens deep underground, the shaking doesn't stay down there. The earthquake waves travel up through the rock and soil to the surface where we live. That's when we feel the ground shake under our feet! Houses might sway gently, and trees might move back and forth. But don't worry - most earthquakes are very small and safe. Scientists watch for earthquakes to help keep everyone safe!