This document provides an introduction to volcanology. It defines a volcano as an opening in the Earth's surface through which lava, gases, and rock fragments erupt. It describes how magma rises from deep underground to form a magma chamber near the surface, which then erupts through a vent to form a volcano. Key parts of a volcano include the vent, crater, lava flows, and sometimes parasitic cones. Volcanoes are often located along tectonic plate boundaries like the Ring of Fire around the Pacific. Earthquakes can provide information about volcanic structures and pathways. Volcanology studies volcanoes and related phenomena, while volcanism describes the geological process of material emerging from the Earth's interior.

1. Introduction to Volcanology November 2009

2. Content 1.- Volcano . Concept. Origin. Parts. Earthquakes, tsunamis and volcanoes. Volcanology. Volcanism.

3. Volcano An opening in the earth’s surface through which lava, hot gases, and rock fragments erupt.

4. Origin of Volcanos 1.- Magma 50-100 miles below the earth’s surface slowly begins to rise to the surface. 2.- As the magma rises it melts gaps in the surrounding rock. 3.- As more magma rises a large reservoir forms as close as 2 miles below the surface (magma chamber) 4.- Pressure from the surrounding rock causes the magma to blast or melt a conduit (channel) to the surface where magma erupts onto the surface through a vent (opening). 5.- The magma, now called lava, builds up at the vent forming a volcano. 6.- Often the volcano sides will be higher than the vent forming a depression called a crater

5. Volcano Mount Saint Helen Eruption, May 18th 1980

6. Magma chamber conduit mantle Parasitic Cone Ash Cloud/Gases Vent Lava Flow Crater Parts of a Volcano

7. “ Ring of Fire” Volcanic arcs and oceanic trenches partly encircling the Pacific Basin form the so-called , a zone of frequent earthquakes and volcanic eruptions.

8. Volcanoes and earthquakes The distribution of earthquakes provides information about magma pathways and the structure of volcanoes and they also can have a lot to do with generating tsunami. Any time that you can somehow displace a large amount of ocean water you generate a large wave or group of waves that goes rushing across the ocean at great speed.

9. Volcanology Volcanology (also spelled vulcanology) is the branch of geology that studies volcanoes, lava, magma and related geological phenomena.

10. Volcanism Volcanism is part of the process of bringing material from the deep interior of a planet and spilling it forth on the surface. In many cases, eruptions build up a piled of material, a mountain what is called volcano.

11. Heat Source The heat from a volcano comes from deep within the earth. Many miles underground, the earth is hot. Rocks beneath the earth are so hot they turn into a liquid called lava. When a volcano erupts, the steam and ash is caused by lava that is forcing its way toward the surface of the earth.