The Volcanoes of Hawaii

These five shield volcanoes are Kilauea, Kohala, Mauna Kea, Hualalai and Mauna Loa.

Kilauea

Kilauea is the most active of the five shield volcanoes, and is also the most active all over the world. In fact, its name is derived from the Hawaiian word which means "spewing" or "much spreading".

Kilauea's most recent eruption on January 3, 1983 marked the beginning of the lava flows that continue until today. It has totally destroyed two towns - Kalapana and Kaimu - as well as Kaimu Bay, Kalapana Black Sand Beach and a chunk of State Route 130. The continuous flows have also resulted into 230 hectares of new land in the Big Island.

Kilauea has a series of vents and a summit caldera that has a pit crater called Halema'uma'u. The current eruption took place from the Pu'u'O'o and Kupaianaha vents. Just recently, on March 19, 2008, the summit crater exploded for the first time since September 1982 and vented out sulfur dioxide gas. The gas prompted officials to close off several roads and trails leading to the crater area.

Kilauea is a major tourist attraction in the state of Hawaii, and is in fact of the Hawai'i Volcanoes National Park. In the middle 1980's, Hawaiians have started calling Kilauea as the "Drive-By Volcano" due to the fact that one can see the amazingly high lava fountains while driving along the highway.

Mauna Loa

Mauna Loa is the other active volcano in the Hawai'i Island. Like Kilauea, Mauna Loa is part of the Hawai'i Volcanoes National Park.

Mauna Loa, whose name means "Long Mountain", is said to have come out of sea level about 400,000 years ago. Located above the continuously drifting Pacific plate, Mauna Loa has been taken slowly away from the Hawaii hotspot from which its magma supply issues. This means that Mauna Loa will become extinct or will have no magma after 500,000 to 1 million years.

Mauna Loa has very shallow slopes because it issues silica-poor lava during eruptions. This means that the lava it issues is fluid. The volcano has had a history of non-violent eruptions, which generally occur at the summit or in either of the two northeast and southwest rift zones.

Mauna Loa's summit caldera measures 3-5 kilometers in diameter, and is thought to have formed from a huge eruption which emptied the magma chamber beneath it leading to its eventual collapse and transformation into a crater. The caldera has recently inflated in 2002, widening at a rate of 2 inches per year. Seismologists have taken this as an indication of an eruption, which has not occurred from Mauna Loa since 1984.

According to seismic data, Mauna Loa has a network of magma chambers beneath it. The summit alone has a 3-kilometer deep magma chamber, while the other two rift zones have their own magma chambers.

Mauna Loa's summit area is the location of the Mauna Loa Observatory - from which the atmosphere is observed - and Mauna Loa Solar Observatory, for observations of the Sun.

Hualalai

Mount Hualalai is one of the three dormant members of the five shield volcanoes of Hawai'i. It has a summit located 8271 feet above sea level, and it has no summit caldera. Instead, it has a collapse crater 0.3-mile wide.

The volcano has not yet erupted since the 1800s, but seismologists have recorded growing earthquake activity on the flanks of the volcano. Because of this, Hualalai is thought to potentially erupt within the next century as the earthquakes were most likely caused by magma climbing from beneath towards the surface of the volcano.

Mauna Kea

Mauna Kea in Hawaiian means "White Mountain." This is because one can see snow caps building up in its summit during the Northern Hemisphere winter.

Mauna Kea is home to several astronomical observatories. This is because Mauna Kea's peak is above the inversion layer, a point in which condensed moisture or smoke stops. This layer makes it possible for astronomers to experience clear nights for observation for the most part of the year.

Kohala

Kohala is a very old volcano in Hawaii, and has since become extinct since its last eruption 120,000 years ago.

In contrast to its younger cousins, Kohala is now in the erosion stage. This means that it is now being crushed by its own weight and slowly collapsing into the ocean's crust. In fact, its southern flanks were overwhelmed by the growth of both Mauna Kea and Mauna Loa. Without any lava flows from eruptions to gain lost ground, Kohala is slowly losing much of itself to natural forces of erosion.

Get Yourself Closer to These Volcanoes

These five shield volcanoes are open for anyone to view and visit. Living in any of the Hawaiian Islands brings you closer to these wonderful land forms than living somewhere else in the world.