Which type of volcano is primarily built from layers of low viscosity lava?

The type of volcano primarily built from layers of low viscosity lava is the shield volcano. These volcanoes are characterized by their broad, gently sloping sides, resembling a warrior's shield lying on the ground. The low viscosity of the lava allows it to flow over long distances, which results in the formation of a wide and expansive structure.

As the lava erupts, it tends to be relatively fluid, enabling it to spread out and create the gentle slopes that define shield volcanoes. This contrasts with other types of volcanoes, where the lava may be more viscous, leading to steeper and more conical shapes. Shield volcanoes are commonly associated with basaltic lava, which is low in silica and thus has a low viscosity. This makes them less explosive compared to other volcano types and allows for a more effusive style of eruption, producing extensive lava flows that contribute to the overall shape of the volcano.

Understanding the characteristics of different volcano types is crucial for comprehending volcanic activity and the geological processes involved.