2. Over 1500 Active Volcanoes in the World

3. Over 600 Have Erupted in the last 50 Years.

4. New Land Forming

11. Most Volcanoes are found along Subduction Zones

13. Ring of Fire

14. Cascades

15. An Island Arc form when two ocean plates form a convergent plate boundary.

16. Indonesia

21. Life Cycle of an Island formed by a Hot Spot

25. Mid-Ocean Ridges

26. Volcanoes of Iceland

34. St. Helens Before & After

35. At 8:32 Sunday morning, May 18, 1980, Mount St. Helens erupted. Shaken by an earthquake measuring 5.1 on the Richter scale, the north face of this tall symmetrical mountain collapsed in a massive rock debris avalanche. Nearly 230 square miles of forest was blown down or buried beneath volcanic deposits. At the same time a mushroom-shaped column of ash rose thousands of feet skyward and drifted downwind, turning day into night as dark, gray ash fell over eastern Washington and beyond. The eruption lasted 9 hours, but Mount St. Helens and the surrounding landscape were dramatically changed within moments. In 1982, the President and Congress created the 110,000-acre National Volcanic Monument for research, recreation, and education. Inside the Monument, the environment is left to respond naturally to the disturbance.

39. Mount St. Helens Blows Smoke on October 1st After Eighteen Years Rest For days the mountain rumbled. And then today, on Friday, October 1st, 2004 at approximately 12:04 Pacific Daylight Time (3 pm EDT) and at 15:14 (6 pm EDT), Washington's Mount St. Helens erupted steam and ash after an eighteen year slumber. The 8,364-foot volcano is located in Kelso, Washington about 30 miles south of Seattle. It is part of a volcanic "ring of fire" so vast that it encircles the Pacific Ocean.