Question

Match each of these volcanic regions with one of the three zones of volcanism (convergent plate boundaries, divergent plate boundaries, or intraplate volcanism): a. Crater Lake b. Hawaii's Kilauea c. Mount St. Helens d. East African Rift e. Yellowstone f. Vesuvius g. Deccan Plateau h. Mount Etna

Short answer

a. Convergent, b. Intraplate, c. Convergent, d. Divergent, e. Intraplate, f. Convergent, g. Intraplate, h. Convergent.

Step-by-step solution

Identify Volcanic Regions with Convergent Plate Boundaries

Volcanic regions that form due to convergent plate boundaries are typically located at subduction zones, where oceanic plates are pushed beneath continental plates, leading to the melting of mantle material and magma production. - Crater Lake, located in the Cascade Range, is a result of subduction along the Pacific and North American plates. - Mount St. Helens and Mount Etna are also examples of volcanoes formed at convergent boundaries due to similar tectonic activity. - Vesuvius, part of the Campanian volcanic arc, also results from the subduction of the African plate under the Eurasian plate.

Identify Volcanic Regions with Divergent Plate Boundaries

Volcanic activity at divergent plate boundaries occurs where tectonic plates are moving apart, allowing magma to rise to the surface and create new crust. - The East African Rift is a classic example of divergent boundaries where continental rifting leads to volcanic activity. No other provided choices match this zone type.

Identify Volcanic Regions with Intraplate Volcanism

Intraplate volcanism occurs away from plate boundaries, often as a result of "hotspots." These are areas where plumes of hot mantle material ascend towards the surface. - Hawaii's Kilauea is an example of a hotspot volcano, located in the middle of the Pacific Plate. - Yellowstone is another hotspot region, known for its geothermal features within a continental setting. - The Deccan Plateau was created by hotspot activity that created extensive basalt flows.

Match the Remaining Region

All the volcanic regions should now have been identified with a zone: - Crater Lake - Convergent Plate Boundary - Hawaii's Kilauea - Intraplate Volcanism - Mount St. Helens - Convergent Plate Boundary - East African Rift - Divergent Plate Boundary - Yellowstone - Intraplate Volcanism - Vesuvius - Convergent Plate Boundary - Deccan Plateau - Intraplate Volcanism - Mount Etna - Convergent Plate Boundary

Key concepts

Convergent Plate Boundaries

Convergent plate boundaries are zones where two tectonic plates move towards each other.
These areas often host subduction zones, where an oceanic plate slips under a continental plate.
This process causes the oceanic plate to melt as it descends into the mantle, creating magma.

• Magma from these areas often rises to form volcanoes.
• This is why many volcanoes are located near convergent boundaries.
• Subduction leads to a line of explosive volcanoes, called a volcanic arc.

Some well-known volcanic arcs include:

• The Cascade Range, featuring Crater Lake and Mount St. Helens.
• The Campanian arc, home to Vesuvius, and the Etna arc, with Mount Etna.

These volcanoes are infamous for their violent eruptions due to high-pressure magma chambers. Understanding these processes helps predict volcanic hazards in such regions.

Divergent Plate Boundaries

At divergent plate boundaries, two tectonic plates are moving away from each other.
This movement allows magma from the mantle to rise and create new crust.
Such zones are often characterized by rift valleys and mid-ocean ridges, where volcanic activity is common.

• Volcanoes formed here are typically less explosive.
• Lava flows are more frequent and can create large stretches of basaltic crust.

The East African Rift is one of the most notable examples of a divergent plate boundary.
This immense rift is gradually splitting the African Plate, leading to a zone rich in volcanic activity. Understanding divergent plate boundaries gives insight into how Earth's surface grows and evolves over time.

Intraplate Volcanism

Intraplate volcanism is a type of volcanic activity that occurs away from plate boundaries.
This phenomenon is linked to hotspots, which are regions of extra hot mantle material rising towards the surface.
Unlike boundary volcanism, hotspots can appear anywhere on the plate.

• They can form islands, like Hawaii, where Kilauea is constantly active.
• Yellowstone, located inland, showcases intraplate volcanism with its geysers and hot springs.
• The Deccan Plateau in India was formed by ancient hotspot activity, evident in its extensive basalt layers.

Since hotspots remain stationary while tectonic plates move over them, they can create chains of volcanoes over geological time. Studying intraplate volcanism allows geologists to learn more about mantle dynamics and the creation of new land features.