GEOLOGY

Detailed explanation-1: -Where a volcano produces low viscosity, runny lava, it spreads far from the source and forms a volcano with gentle slopes: a shield volcano. Most shield volcanoes are formed from fluid, basaltic lava flows. Mauna Kea and Mauna Loa are shield volcanoes.

Detailed explanation-2: -Each type is named for its shape or interior structure. A quiet eruption of low-viscosity lava produces a wide, flat volcano called a shield volcano. If an eruption is entirely ash and cinders, the result will be a small, steep-sided volcano called a cinder cone.

Detailed explanation-3: -Most shield volcano eruptions are nonexplosive (effusive), usually 0-1 on the Volcanic Explosivity Index (VEI), typically in the Hawaiian eruptive style. These eruptions produce fluid lava flows and may produce fire-fountains. High rates of eruptions help produce lava flows that travel fast and can cover large areas.

Detailed explanation-4: -Quiet Eruption A volcano erupts quietly if its magma is low in silica. Low-silica magma is thin and runny and flows easily. The gases in the magma bubble out gently. Low-silica lava oozes quietly from the vent and can flow for many kilometers.

Detailed explanation-5: -Eruptions at shield volcanoes are only explosive if water somehow gets into the vent, otherwise they are characterized by low-explosivity fountaining that forms cinder cones and spatter cones at the vent, however, 90% of the volcano is lava rather than pyroclastic material.