Hawaii Volcanoes 

for current lava flow info:    http://volcano.wr.usgs.gov/hvostatus.php

Hawaii Volcanoes National Park

   The Hawaiian Islands are volcanic in origin. The Hawaiian hot spot  has created 82 volcanoes that stretches for more than 1,500 miles to form the Hawaiian Islands. The source of this heat could lie as deep as 2000 miles underground. This "hot spot" is formed by magma (molten lava) punching through the tectonic plate and erupting continuously for at least some 70 million years to create the islands. As the plate moves away (at 5-10 cm/yr) the volcanoes stop erupting. The Hawaiian Islands are moving across the Pacific Ocean at about the same speed that your fingernails are growing. The life of a Hawaiian volcano before it sinks back under the sea floor is between 5 and 10 million year.


The Big Island of Hawaii is constructed of 5 shield volcanoes: Kilauea, Mauna Loa, Mauna Kea, Hualalai, and Kohala. Mauna Loa is the largest active volcano and most massive mountain on earth occupying an area of 10,000 cubic miles. Mauna Kea at 13,796 feet is the highest. Kilauea (4093 feet) is the youngest and one of the world's most active with it's satellite vent Pu'u O'o the source of the current lava flows. The Kilauea caldera is about two miles wide and more than three miles long. Most of the Kilauea caldera formed shortly before and during the eruption of 1790. Calderas are large collapsed craters that are formed by magma draining away along the rift zones within the volcano. A caldera is the actual caving in of the top of the mountain.
 
As you move from the islands of Hawaii to Kauai, the volcanoes become older and older. Oahu's volcanoes have not erupted for a million years. There are three volcanoes that are active in Hawaii: Kilauea that has been active since 1983, Mauna Loa which last erupted in 1984 and Loihi the submerged volcano that lies about thirty miles off the southern coast of Hawaii, 3,000 feet under the sea surface and is expected to emerge in a thousand centuries. Legends of PELE, the goddess of volcanoes, tells about her search for a home, moving down the chain of islands digging her fire pits until she arrived at Kilauea where she made her home in the lava filled craters. 

There are two types of lava flow: 'a 'a and pahoehoe. 'A 'a is rough and clinkery with sharp, jagged rocks. Pahoehoe flows are fluid with less gas content so the surface appears smooth sometimes ropy. Lava tubes are formed in pahoehoe lava flows when the surface flows harden while the lava in the interior is still molten. The lava then drains out of the flow from below, leaving a tunnel or tube. Some tubes can be as large as a subway tunnel.

Hawaiian eruptions are generally non-explosive because the magma's high temperatures (1,200C) as it reaches the surface makes it very liquid. They erupt not only at their summits but also along rift zones, which are fractured zones of weakness within the volcano. Kilauea has two rift zones.

Hawaii Volcanoes National Park was the first national park in Hawaii and the eleventh in the United States. The Park covers 200,000 acres of land.

Hawaii Volcanoes National Park
RT11 Hawaii Belt Highway
PO Box 52
Hawaii Volcanoes National Park, Hi. 96718
808-985-6000