1. How do convergent boundaries contrast with divergent boundaries in the context of Earth's crust?
- A. Convergent boundaries create crust, while divergent boundaries destroy it.
- B. Convergent boundaries destroy crust, while divergent boundaries create new crust.
- C. Both boundary types only involve plates sliding past each other.
- D. Convergent boundaries are only found on land, while divergent boundaries are only in the ocean.
2. The Earth's size remains relatively constant over geologic time. Which process is essential for maintaining this balance against the creation of new rock?
- A. The rapid erosion of continental mountain ranges by wind and water.
- B. The formation of new crust at mid-ocean ridges which pushes continents apart.
- C. The subduction and melting of old tectonic plates at convergent zones.
- D. The gradual cooling and contraction of the Earth's inner core.
3. If the process of subduction at convergent boundaries were to stop completely, but seafloor spreading at divergent boundaries continued, what would be the most likely long-term consequence for Earth?
- A. The planet would start to expand in size.
- B. The planet would begin to cool down rapidly.
- C. The continents would stop moving entirely.
- D. The amount of volcanic activity would cease globally.
4. The destruction of rock at a convergent boundary is a direct result of which specific geologic process?
- A. Seafloor spreading
- B. Continental rifting
- C. Subduction
- D. Erosion
5. What is the primary geologic outcome at a convergent plate boundary involving subduction?
- A. The formation of new oceanic crust from rising magma.
- B. The destruction and recycling of old crust back into the mantle.
- C. The horizontal sliding of two plates past one another.
- D. The separation of a continental plate into two smaller pieces.
6. If you were to map the locations of a deep ocean trench and its associated volcanic arc, what spatial relationship would you expect to find?
- A. They are parallel to each other.
- B. They are perpendicular to each other.
- C. The volcanic arc is located inside the trench.
- D. Their locations are random and unrelated.
7. A team of geologists discovers a chain of active volcanoes on a continent near the coast. What other feature would they search for offshore to confirm that these volcanoes are the result of subduction?
- A. A shallow, wide continental shelf.
- B. An extremely deep valley on the ocean floor.
- C. A series of underwater mountains spreading apart.
- D. A long, straight fault line with horizontal movement.
8. The presence of a deep-sea trench and a parallel line of volcanoes are described as the "signature fingerprints" of what geological setting?
- A. A divergent boundary
- B. A transform boundary
- C. A continental rift zone
- D. A convergent boundary
9. What is the direct cause of magma formation that leads to a volcanic arc at a subduction zone?
- A. Friction from the two plates rubbing together directly melts the rock of the overriding plate.
- B. The subducting plate dives into the Earth's core and melts, sending magma back to the surface.
- C. Fluids released from the sinking plate lower the melting point of the hot rock above it, causing it to melt.
- D. Intense pressure at the bottom of the trench squeezes rock until it becomes molten magma.
10. Why are oceanic trenches the deepest parts of the ocean?
- A. They are ancient river valleys that were flooded as sea levels rose over millions of years.
- B. They are carved out by powerful, focused deep-ocean currents over long periods.
- C. They are locations where a tectonic plate is actively bending and being forced downward into the mantle.
- D. They are simply gaps left between two continental plates that have drifted apart.