Forces within the Earth cause earthquakes and volcanoes, which both release large amounts of energy that can impact the Earth's surface. Earthquakes occur when rocks break along faults due to movement of tectonic plates, while volcanoes form when magma escapes through openings where plates are moving or at hot spots, building up from eruptions of ash and lava. Recent examples of devastating earthquakes and volcanoes include those in Japan.

1. Introduction to Earth Processes 8SCIENCE: Mon. April 4, 2011

3. What are Earth Processes? Forces within the earth How earthquakes and volcanoes are related to movements inside the earth Both release great amounts of energy that can have effects on the Earth’s surface Both can have devastating effects Most recently in seen in Japan

4. Earthquakes Rocks move and break along surfaces called faults Vibrations caused by rocks breaking along faults Usually results from plates (large pieces of the Earth) that are moving under, over or past each other

5. Volcanoes Opening in Earth’s surface Can form a mountain when layers of ash and lava build up Are found where plates (large pieces of the Earth) are moving apart or together or at hot spots Most of Earth’s volcanoes are not active