Volcanism along a continental arc is dominated by the eruption of ________.
A)basaltic lava flows
B)andesitic lavas and pyroclastic materials
C)rhyolitic pyroclastic materials and lavas
D)ophiolites

Question

Quizplus · Accepted Answer

Continental arcs are created by the subduction of oceanic lithosphere beneath a continental plate. The magma generated from this subduction is typically andesitic in composition, which is why the eruptions along a continental arc are dominated by andesitic lavas and pyroclastic materials. Basaltic lavas are generally associated with mid-ocean spreading ridges, while rhyolitic materials are more commonly found in continental rift zones. Ophiolites are remnants of oceanic crust that have been emplaced onto a continent through tectonic processes and are not directly related to volcanic activity.

Volcanism Along a Continental Arc Is Dominated by the Eruption