The tectonic plates that make up the earth's crust are moving constantly. As the edges of these plates slide against each other in fault zones, friction can slow them down, leading to the buildup of pressure over long periods of time. When the force of movement finally overcomes the friction, sections of the crust suddenly break or become displaced, releasing the pent-up pressure in the form of seismic waves. This is a naturally occurring earthquake, sometimes referred to as a tectonic earthquake. “
