shield volcanoes of hawai'i are built of lava that erupts quietly, with little explosion. lava...

Shield volcanoes of Hawai'i are built of lava that erupts quietly, with little explosion. Lava from shield volcanoes move rapidly for a long distance before cooling. It is called a shield volcano because it has a

wide rounded top that resembles a warrior's shield laying flat on the ground.

Shield Volcano

Mauna Loa

The Kilauea Iki eruption began on the morning of November 14, 1959, three months after a rapid increase in inflation of the ground surface and the number and size of earthquakes. The eruption started halfway up the 600-650 foo (180-200 m) south wall of the crater as a curtain of fire a half-a-mile (0.8 km) long. Lava was ejected up to 100 feet (30 m) in the air. Photo courtesy of the U.S. Geological Survey.

Cinder Cone Volcano

Capulin Volcano in New Mexico

Wizard Island in the center of Crater Lake in Oregon

Composite Volcano

Mount Shasta in California

Mount St Helens, a composite volcano

May 18, 1980

The May 18, 1980, eruption sent an ash plume over 15 miles into the atmosphere. Prevailing winds carried the ash plume to the northeast, where it turned daylight to darkness over 120 miles away

beforePrior to the eruption high mountain lakes like Obscurity Lake, 10 miles north of Mount St. Helens, were characteristically clear due to extremely low levels of dissolved nutrients

afterThe same view after the eruption shows the extent of eruption damage to the forest surrounding Obscurity Lake. Note the large quantity of volcanic ash that was eroded from adjacent hillsides and deposited on large deltas at the mouth of inlet streams.

A pre-eruption view of Mount St. Helens from Spirit Lake shows the smooth, conical slopes of a very young, and potentially explosive volcano.

The same view shows the profound change in the

volcano and Spirit Lake. The formerly clear mountain lake

had been completely displaced by the massive

landslide and choked with ash and organic debris