In
volcanology, a
pyroclastic shield or
ignimbrite shield is an uncommon type of
shield volcano. Unlike most shield volcanoes, pyroclastic shields are formed mostly of
pyroclastic and highly
explosive eruptions rather than relatively fluid
basaltic lava issuing from vents or
fissures on the surface of the volcano. They typically display low-angle flank slopes and often have a central
caldera caused by large eruptions. Lava is commonly extruded after explosive activity has ended. The paucity of associated
Plinian fall deposits indicates that pyroclastic shields are characterized by low Plinian columns.