Question

what is the reason for earthquake

Answer 1

the reason of earthquake is inside the earth crust tectonic plates combine each other that 's why
start the earth crust

Answer 2

Our earth's surface is not unified. It was broken and several plates together form the surface of the earth. These plates are known as technotic plates. These plates will not be stabled. They'll be moving always. Due to their movement only, we felt earth quakes.

Hope this helps you