The Wrangell Mountains form the volcanic heart of the park.
Covering over 2,000 square miles, the Wrangell Volcanic Field is
made up of thousands of lava flows and some of the highest peaks
in North America, and includes Mount Wrangell, one of the
largest (by volume) active volcanoes in the world. The Wrangell
volcanoes were formed over the last 5 million years by massive
eruptions which were the result of tectonic collisions along the
Pacific and North American crustal plates. Although this
activity has slowed for the past few thousand years, there is
still heat at depth, as evidenced by Mount Wrangell's steam
plumes, and the series of active mud volcanoes east of
Glennallen. Did You Know? Since 1889, Alaska has experienced 10
earthquakes with a magnitude greater than 8.0 on the Richter
scale