This is an image of Mauna Kea erupting.
Click on image for full size
Image from: U.S. Geological Survey
Shield volcanoes can grow to be very big. In fact, the oldest continental regions of Earth may be the remains of ancient shield volcanoes.
Unlike the composite volcanoes which are tall and thin, shield volcanoes are tall and broad, with flat, rounded shapes. The Hawaiian volcanoes exemplify the common type of shield volcano. They are built by countless outpourings of lava. The outpourings of lava are typically not accompanied by ash, which make the shield volcanoes relatively safe, as shown in this picture of scientists monitoring the eruption.
Famous shield volcanoes include Mauna Loa, Kilauea, (two of the world's most active volcanoes), andOlympus Mons of Mars.
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