Discuss the processes involved in volcanism. Highlight the major volcanic regions in the world and their associated tectonic settings.

Major volcanic regions of the world and associated tectonic settings:

[Diagram: World map showing Andes Mountains, Alacama boundary, Italy (Mt Vesuvius), Pacific plate, India plate, Ring of Fire]

The major volcanic regions lie around the Ring of Fire - along the boundaries where Pacific plate meets the other land plates such as American plate, Eurasian plate. Indonesia is one of the most volcanically active country along with Philippines.

The divergent plates such as Mid-Atlantic Oceanic ridge shows some activity.

The volcanism offers opportunity to understand the interior of earth. They are also major source of precious natural S. Thus process of volcanism is an important geological phenomenon.