The Dynamic Earth View Multimedia Version

Main Menu >  Plate Tectonics and Volcanoes  >  Above Hot Spots  >  Hawaiian Islands
TITLE: Hawaiian Islands


[Photo: Erupting Volcano]
Twilight falls on the island of Hawaii, highlighting lava pouring from vents on Kilauea's east rift zone. Currently sitting on a hot spot, Kilauea is one of Earth's most active volcanoes.

 





The Hawaiian Islands belong to a volcanic chain that formed on the Pacific Plate over the last 80 million years. As the plate passes over a hot spot, molten rock erupts and builds volcanoes. More than 100 volcanoes have formed above this hot spot... and more are on the way.

  [Photo: Pacific Plate]

Above the Hawaiian Hot Spot

Like all hot spots, the Hawaiian plume originates deep within Earth's mantle. The plume remains stationary while the Pacific Plate above it moves northwest. Like a giant conveyor belt, the plate carries older volcanoes away from the hot spot. This hot spot is currently feeding two volcanoes on Hawaii
and a submarine volcano just south of the island.

  [Photo: Cross section]

Kilauea

Kilauea's "fire hose" pours lava from a sea cliff. One of five volcanoes that built the big island of Hawaii, Kilauea's roaring lava fountains and fluid lava streams create products of remarkable diversity.

  Photo: Pele's Hair Photo: Pele's Tears Photo: Dunite in Basaltic Lava  
 

Pele's Hair

  Pele's Tears   Dunite in
Basaltic Lava
 

 

  [Photo: Kilauea's "fire hose"]

Inside Kilauea

A balloon-like reservoir underlies Kilauea's summit. Magma rising from the mantle hot spot inflates this reservoir, sometimes triggering eruptions in the summit crater. More often, though, the magma travels laterally to erupt on the volcano’s flank.

  [Photo: Summit crater and Magma reservoir and Rift zone eruption]

Where Kilauea Erupts

Most eruptions occur along Kilauea's east rift zone, an area of weakness that extends 120 km (75 mi) from the summit to the volcano's flanks on the ocean floor. Kilauea also erupts from its southwest rift zone and at its summit. Perhaps once a century, explosive and extremely dangerous summit eruptions occur.

  [Photo: Historic Lava Flows]

Jagged and Rumpled

These three lava samples are all basalts of similar composition. The two upper samples of Pahoehoe (pa-HOY-hoy) come from hot and fluid lava, which hardens into twisted, rumpled shapes. Aa (ah-ah) lava is slightly cooler and breaks into jagged chunks.

  [Photo: Singed geology pick, Pahoehoe Lava, and Aa lava]

The Next Hawaiian Island

As the Pacific Plate carries the island of Hawaii off the hot spot, the next volcano — Loihi (Low-EE-he) is slowly growing about 40 km (25 mi) to the south. If eruptions continue, Loihi will form an island in 10,000 to 50,000 years and then merge with Hawaii.

Loihi today: Its summit is 970 m (3,200 ft) below sea level and visible only from research submersibles.

Loihi in the future: It will emerge from the sea, form an island, and eventually join the big island of Hawaii.

  [Photo: Lohi today]
[Photo: Lohi in the future]

Bottom Navigation Bar

 

Smithsonian National Museum of Natural History Department of Mineral Sciences website Credits