Shield volcanoes are composed primarily of:

A) basalt lava flows
B) andesite lava flows
C) rhyolite lava flows

Shield Volcanoes

These are characterized by their extensive size and gentle slopes, produced by the effusion of low-viscosity lava that can travel far from the source.

Basalt Lava

Molten rock that emerges from the earth during a volcanic eruption, characterized by its high iron and magnesium content, and low viscosity.