Volcanoes occur at convergent, divergent, and hotspot tectonic plate boundaries.
1. Convergent Boundary: When two tectonic plates collide, one plate is typically forced beneath the other in a process called subduction. Volcanic activity is common along subduction zones, where the descending plate melts and generates magma. This magma then rises to the surface, forming volcanoes. Examples of convergent boundary volcanoes include the Cascade Range in the western United States and the Andes Mountains in South America.
2. Divergent Boundary: At divergent plate boundaries, two tectonic plates move away from each other, creating a gap known as a rift. In these regions, magma from the mantle rises to fill the gap, leading to volcanic activity. Volcanoes formed at divergent boundaries often create a chain or ridge. The Mid-Atlantic Ridge is an example of a volcano formed at a divergent boundary.
3. Hotspot: Hotspots are areas of intense volcanic activity that occur within tectonic plates, rather than along plate boundaries. They are thought to be caused by mantle plumes, which are columns of exceptionally hot mantle material rising from Earth's core-mantle boundary to the surface. As the plate moves over the fixed hotspot, a chain of volcanoes is formed, with the oldest volcano being farthest from the current activity. The Hawaiian Islands, with their volcanic chain, are a notable example of a hotspot volcano.
In summary, volcanoes can form at convergent boundaries through subduction, at divergent boundaries through the upwelling of magma from the mantle, or within tectonic plates at hotspots caused by mantle plumes.
Select one of the following: mountains, volcanoes, earthquakes, rift valley
Identify the tectonic plate boundary at which this feature occurs. (1 point)
Explain how your chosen feature is formed by the movement of plates. (2 points)
1 answer
5 answers