Plate Tectonics Quiz
Questions: 16 · 10 minutes
1. Continental crust is stretching, thinning, and developing parallel faults with a central rift valley. If extension continues for millions of years, what may eventually form?
A continent-continent collision zone
A new ocean basin with a spreading center
A transform fault that consumes both plates
A volcanic island arc above ocean-ocean subduction
2. A geologist samples basalt at several distances from a mid-ocean ridge. Which age pattern would support seafloor spreading?
The oldest basalt occurs at the ridge, and the youngest lies near continents
All basalt has the same age regardless of its distance from the ridge
The youngest basalt occurs at the ridge, with progressively older basalt farther away
Basalt ages vary randomly on both sides of the ridge
3. Identical fossils of a land-dwelling organism are found in rocks of the same age on continents now separated by an ocean. Why does this support continental drift?
The fossils show that the ocean floor is older than every continent
The organism must have crossed the modern ocean on floating sea ice
Ocean currents routinely preserve identical land fossils on different continents
The continents were once connected, allowing the organism to occupy both areas
4. A long fault zone has frequent shallow earthquakes, little volcanism, and two crustal blocks moving horizontally in opposite directions. Which boundary is the best match?
A continent-continent convergent boundary
A transform boundary
An oceanic spreading center
An ocean-continent subduction boundary
5. What is most likely to form where one oceanic plate subducts beneath another oceanic plate?
A continental rift valley and fault-block mountains
A broad fold mountain range made only of continental crust
A deep-ocean trench and a volcanic island arc
A mid-ocean ridge with no significant earthquakes
6. At which type of plate boundary do plates mainly slide horizontally past one another?
Oceanic divergent boundary
Continental collision boundary
Transform boundary
Subduction boundary
7. A chain of volcanic islands becomes progressively older toward the northwest, while the southeastern island is volcanically active above a relatively stationary hotspot. In which direction has the plate mainly moved?
Southeast
The plate has remained stationary
Northeast
Northwest
8. Which process best explains the formation of the Himalayas?
An oceanic plate moving over a mantle hotspot
Two continental plates colliding and compressing the crust
An oceanic plate sliding horizontally past a continent
Two oceanic plates separating at a ridge
9. Scientists find matching bands of normal and reversed magnetic polarity on opposite sides of a mid-ocean ridge. What is the best explanation?
Earth's magnetic field prevents plates from moving across the ridge
Continental rocks migrate across stationary oceanic crust
New crust forms at the ridge and moves outward while recording magnetic reversals
Subduction repeatedly pulls the same crust back through the ridge
10. What does the term “slab pull” describe?
A dense, sinking plate edge helping draw the rest of the plate toward a subduction zone
Magma at a ridge pushing continents upward without horizontal motion
Tides dragging oceanic plates toward coastlines
Earthquakes pulling two transform plates away from each other
11. Two oceanic plates are moving apart along a mid-ocean ridge. What process occurs between them?
Old oceanic crust folds into a mountain belt
Continental crust is converted directly into mantle rock
One plate sinks beneath the other without volcanism
Magma rises and solidifies to form new oceanic crust
12. Through which process is large-scale oceanic lithosphere primarily returned to Earth's mantle?
Sediment deposition
Seafloor spreading
Continental rifting
Subduction
13. Which part of Earth is divided into the rigid plates described by plate tectonics?
The lithosphere
The asthenosphere
The outer core
The lower mantle
14. An oceanic plate is moving toward a continental plate. Which combination of features is most likely to develop?
An ocean trench and a volcanic mountain chain on the continent
A mid-ocean ridge and symmetrical magnetic stripes
A rift valley and new continental crust
A broad plateau with no earthquakes or volcanism
15. GPS stations on opposite sides of a boundary show that the stations are moving steadily away from each other. Which interpretation is most consistent with the data?
The boundary is convergent because both plates are being compressed
The boundary is divergent because the plates are separating
The plates are stationary, and only sea level is changing
The boundary is transform because the stations are moving parallel to it
16. Earthquake records reveal progressively deeper earthquake foci beneath a continent as distance from an offshore trench increases. What does this pattern indicate?
An oceanic plate is descending beneath the continent
The continent is splitting symmetrically at a divergent boundary
A mantle plume is rising vertically beneath the continent
Two plates are sliding past each other only at the surface