GEOLOGY

Detailed explanation-1: -Composite volcanoes are built up by successive eruptions of domes, lava flows and pyroclastic flows, but also can experience large blasts that destroy large areas of their summits, such as the May 1980 explosion and landslide at Mount St. Helens.

Detailed explanation-2: -Composite Volcano: A composite volcano has high levels of dissolved gas and silica and erupts explosively.

Detailed explanation-3: -Composite volcanoes: steep slopes; thick, sticky lava; lava does not flow quickly or far; erupt violently. Shield volcanoes: gentle slopes; runny lava; lava flows quickly; lava may flow far; erupt less violently.

Detailed explanation-4: -As was demonstrated by the 1980 eruption of Mount St. Helens, composite volcanoes can explode violently. Stratovolcano shapes are more variable than these classic examples, primarily because of wide variations in eruptive style and composition.