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Haleakala National Park

History: How Haleakala Was Formed
©2006 National Park Services Haleakala is sacred to the Hawaiians. The remains of ancient stone structures within its crater indicate that religious ceremonies were held here more than a thousand years ago.

Haleakala has not had a major eruption since about 1790, according to both Hawaiian legend and records kept by Europeans. Maps and charts made by early European explorers show significant changes in the island's topography that probably resulted from the flow of lava. But even though Haleakala is dormant, nobody would call it extinct.

Earthquakes on Maui indicate to geologists that the great volcano still rumbles far below the surface, and islanders adamantly believe the sleeping mountain will wake up breathing fire again within a century. 

Haleakala's gigantic crater was not created by the kind of explosion that blew the top off Mount St. Helens in 1980. After thousands of eruptions built up the mountain from the bottom of the Pacific Ocean, a climatic change brought long-lasting torrential rains. Water flowing down the sides of the peak turned into huge rivers pouring from the summit. These raging streams cut long, deep valleys down the flanks of the mountain. The crater was created as two of the valleys joined at the mountaintop and eventually eroded it into the vast amphitheater.

The Formation of a Pacific Volcano

For centuries, Hawaiian legends have explained the way these volcanic islands have been formed: Pele, the goddess of fire, moves from place to place around the islands. As she tells others the story of her travels, she stamps her foot, making the earth tremble and forming a new island.

Geologists know that there is some truth to this legend. The spot where an island is likely to appear does move from place to place. Scientists explain this with a theory of "hot spots" and plate tectonics. For some unknown reason, there are more than 100 hot spots beneath the earth's surface. These places produce more molten rock, or magma, than is produced elsewhere. The Hawaiian hot spot, it turns out, is one of the largest.

The hot spots are stationary, but the dozen or so great plates that make up the crust of the earth are not. The Pacific plate is in constant motion at the rate of about four inches a year. As the plate moves over the Hawaiian hot spot, enough magma rises to create a new island. This young island is pulled away from the hot spot by the movement of the plate, and in time another island forms over the hot spot.

Haleakala National Park is an environment that is truly unique. It offers sightseers peeks at lush rain forests, stunning waterfalls, and unearthly volcanic landscapes.

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