Three Types of Three Types of VolcanoesVolcanoes

Shield VolcanoesShield Volcanoes

Low silica levelLow silica level Low viscosity LavaLow viscosity Lava High or low levels of gasHigh or low levels of gas Low to medium explosivityLow to medium explosivity Flattened moundFlattened mound Resembles a warrior’s shieldResembles a warrior’s shield

Mauna Loa, HawaiiMauna Loa, Hawaii

Piton de la FournaisePiton de la Fournaise

Surtsey, FinlandSurtsey, Finland

Composite VolcanoesComposite Volcanoes

High in silicaHigh in silica High viscosity magmaHigh viscosity magma High levels of gasHigh levels of gas Highly explosiveHighly explosive Cone shapedCone shaped Formed by layers of lava and ashFormed by layers of lava and ash

Mt. Rainier, WashingtonMt. Rainier, Washington

Mt. Fuji, JapanMt. Fuji, Japan

Mt. St. Helens, WashingtonMt. St. Helens, Washington

CinderconesCindercones

Low silica lavaLow silica lava High levels of gasHigh levels of gas ““Fire-fountain” eruptionsFire-fountain” eruptions Commonly found on the flanks of Commonly found on the flanks of

shield volcanoesshield volcanoes Made from a pile of rock piecesMade from a pile of rock pieces Structurally weakStructurally weak

Pu'u ka Pele, HawaiiPu'u ka Pele, Hawaii(on the flanks of Mauna Loa)(on the flanks of Mauna Loa)

FloreanaFloreana Island, Galapagos Island, Galapagos

Puu OO, HawaiiPuu OO, Hawaii