Which type of volcano is characterized by symmetrical cones with layers of lava and pyroclastic material?

The type of volcano characterized by symmetrical cones formed from alternating layers of lava flow and pyroclastic materials is the composite volcano, also known as stratovolcanoes. These formations are typically steep-sided and exhibit a conical shape due to the many eruptions over time that create distinct layers.

Composite volcanoes erupt eruptions that can range from explosive to effusive, resulting in the build-up of both lava and tephra. This layered structure contributes to their characteristic steep profile. The eruptions can produce pyroclastic flows, ash fall, and lava flows, which add to the complexity and beauty of these volcanoes.

In contrast, cinder cone volcanoes are typically smaller and have a simpler structure, composed mainly of small fragments of lava that accumulate around a single vent. Shield volcanoes have broad, gentle slopes built primarily from low-viscosity lava that flows over great distances, creating a shield-like profile. Fissure volcanoes do not form traditional volcano structures; instead, they are characterized by cracks in the Earth’s surface where lava erupts to form extensive lava fields. Each of these types has distinct features that differentiate them from composite volcanoes.