Volcanoes the benefits Likely original source of water. Source of our early atmosphere. Provide us with a glimpse of the Earth s interior.
Volcanic ash provides much needed nutrients for plants.
Volcano Basics Active currently erupting or erupted within the past few thousand years. Extinct no evidence of eruption in the past 10 thousand years. Active Slopes of this volcano in Alaska show little sign of erosion, indicating the volcano is still active. Dormant Slopes of Mt. Rainier in Washington show greater sign of erosion, indicating the volcano is dormant. Extinct Slopes of this volcano in Arizona show long periods of erosion and well-established vegetation, indicating the volcano is no longer active.