What geological process is associated with the formation of volcanic arcs?

What geological process is associated with the formation of volcanic arcs?

• A. Divergent boundary activity
• B. Transform boundary activity
• C. Convergent boundary activity
• D. Stationary plate tectonics

Answer: (C)

The formation of volcanic arcs is primarily associated with convergent boundary activity. At convergent boundaries, two tectonic plates collide, often resulting in one plate being forced beneath the other in a process known as subduction. This typically occurs when an oceanic plate converges with a continental plate or another oceanic plate, leading to the formation of deep ocean trenches and volcanic activity. As the subducted plate descends into the mantle, it undergoes pressure and temperature changes, which facilitate the melting of both the subducting and overlying materials. The magma that rises from this melting process can lead to the formation of chains of volcanoes on the surface, which are known as volcanic arcs. This is characteristic of regions such as the Pacific Ring of Fire, where several volcanic arcs coincide with plate tectonic boundaries. Divergent boundary activity, on the other hand, typically results in the formation of new oceanic crust as plates pull apart, while transform boundary activity involves lateral sliding of plates without significant vertical movement or magma generation. Stationary plate tectonics does not directly relate to the dynamic processes involved in volcanic activity.

The formation of volcanic arcs is primarily associated with convergent boundary activity. At convergent boundaries, two tectonic plates collide, often resulting in one plate being forced beneath the other in a process known as subduction. This typically occurs when an oceanic plate converges with a continental plate or another oceanic plate, leading to the formation of deep ocean trenches and volcanic activity.

As the subducted plate descends into the mantle, it undergoes pressure and temperature changes, which facilitate the melting of both the subducting and overlying materials. The magma that rises from this melting process can lead to the formation of chains of volcanoes on the surface, which are known as volcanic arcs. This is characteristic of regions such as the Pacific Ring of Fire, where several volcanic arcs coincide with plate tectonic boundaries.

Divergent boundary activity, on the other hand, typically results in the formation of new oceanic crust as plates pull apart, while transform boundary activity involves lateral sliding of plates without significant vertical movement or magma generation. Stationary plate tectonics does not directly relate to the dynamic processes involved in volcanic activity.