GED Science TestEarth and Space ScienceMedium
A geophysicist is studying the movement of Earth's tectonic plates. She observes that two plates are moving towards each other, with one plate being forced beneath the other into the mantle. Which of the following geological features is most characteristic of this type of plate boundary?
- ALarge transform faults and shallow earthquakes.
- BBroad, flat plains with minimal seismic activity.
- CMid-ocean ridge and rift valleys.
- DDeep ocean trenches and volcanic island arcs or mountain ranges.
Show answer & explanationAnswer & explanation
Correct answer: D. Deep ocean trenches and volcanic island arcs or mountain ranges.
When two plates converge and one subducts beneath the other, it forms a subduction zone. This process is characterized by deep ocean trenches (where the plate descends) and volcanic activity, leading to island arcs (oceanic-oceanic convergence) or mountain ranges with volcanoes (oceanic-continental convergence).
Why the other options are wrong
- A. Large transform faults (like the San Andreas Fault) and shallow earthquakes are characteristic of transform plate boundaries, where plates slide past each other.
- B. Broad, flat plains with minimal seismic activity are typically found away from plate boundaries.
- C. Mid-ocean ridges and rift valleys are characteristic of divergent plate boundaries, where plates move apart.
Convergent Plate Boundary
A plate boundary where two tectonic plates move towards each other, resulting in collision, subduction, or mountain building.
- Three types: oceanic-oceanic, oceanic-continental, continental-continental.
- Features include deep ocean trenches, volcanic arcs, mountain ranges, and strong earthquakes.
- Subduction occurs when one plate dives beneath another.
Memory trick: Converging Creates Canyons and Cones.