About Mount St Helens:
- It is a volcanic peak in the Cascade Range of southwestern Washington, United States of America.
- It is part of the larger Pacific Ring of Fire.
- The volcano was formed during four eruptive stages beginning about 275,000 years ago and has been the most active volcano in the Cascade Range during the Holocene.
Its eruption on May 18, 1980, was one of the greatest volcanic explosions ever recorded in North America.
Key points about Pacific Ring of Fire
- It also known as the Circum-Pacific Beltis a path along the Pacific Ocean characterized by active volcanoes and frequent earthquakes.
- Its length is approximately 40,000 kilometres (24,900 miles).
- It traces boundaries between several tectonic plates—including the Pacific, Juan de Fuca, Cocos, Indian-Australian, Nazca, North American, and Philippine Plates.
