Ohio Assessment for Educators (OAE) Integrated Science (024) Practice Exam

What geological feature results from hotspot volcanism?

1. Cinder cones

2. Shield volcanoes

3. Stratovolcanoes

4. Calderas

The correct answer is: Shield volcanoes

Hotspot volcanism primarily leads to the formation of shield volcanoes. This geological feature is created when magma from a hotspot—a stationary plume of hot mantle material—rises through the Earth's crust. As this magma erupts, it typically flows out smoothly and spreads over large areas, resulting in the broad, gently sloping structure characteristic of shield volcanoes. A distinguishing feature of shield volcanoes is their low profile and fluid lava flow, which contrasts with other volcanic types. The Hawaiian Islands, a prime example of hotspot volcanism, are predominantly comprised of shield volcanoes. Over time, the continuous eruption at the same hotspot can lead to the formation of a volcanic island chain as the tectonic plate moves above the stationary hotspot. Understanding the mechanism of hotspot volcanism is crucial for recognizing its outcomes and the unique characteristics that define shield volcanoes compared to other volcanic types, such as cinder cones or stratovolcanoes, which have different eruption dynamics and geological formations.