Hi, I am Jiwoo. Last summer, my family took a trip to Jeju Island. We hiked part of the way up Hallasan, the tallest mountain in South Korea. When Dad told me that Hallasan is a volcano, I was very surprised.
Dad said that it is very hot deep under the ground. Some rocks there melt, and this melted rock is called magma. When magma comes out of a volcano, people call it lava. The black rocks all over Jeju were made from lava that cooled and turned hard.
I felt a little nervous, but Dad smiled at me. He said that Hallasan has been quiet for thousands of years, and scientists check it often. Next, I asked him how earthquakes happen. Dad told me that the outside of the Earth is made of giant pieces of rock called plates.
These plates move very slowly, about as fast as your nails grow. Sometimes the edges of two plates get stuck and then slip all at once. When that happens, the ground shakes, and we call it an earthquake.
At school, we often practice earthquake safety. First, we get under our desks and cover our heads. We hold on to the desk legs until the shaking stops. Then our teacher leads us down the stairs, not the elevator, to the open playground.
Now I know that the Earth is always slowly changing. If we learn the facts and practice what to do, we can stay safe and calm.