Tectonic Plate Questions

Why are the continents older than the seafloor?

The continental crust is less dense and does not get subducted at convergent boundaries therefore it is older.

Define Convergent Boundary

A plate boundary where two plates move toward each other.

Water causes partial melting of the mantle at which type of plate boundary? A. Convergent boundaries. B. Divergent boundaries. C. Transform-fault boundaries.

A. Convergent boundaries.

What is the ultimate cause of plate tectonics? A. Heat transfer away from Earthʼs interior. B. Combined lunar and solar tides. C. Seafloor spreading. D. Continental drift.

A. Heat transfer away from Earthʼs interior.

Transform-fault boundaries usually form A. between two segments of a mid-ocean ridge. B. between two other transform-fault boundaries. C. between a mid-ocean ridge and a subduction zone. D. in the rift of a mid-ocean ridge

A. between two segments of a midocean ridge.

The flowing molten outer core is responsible for: A. Earthʼs stable, consistent magnetic field. B. Earthʼs magnetic-pole reversals. C. The presence of iron and nickel in the inner core. D. All of the choices.

B. Earthʼs magnetic-pole reversals.

How did seafloor spreading suggest a driving force for continental drift? A. Youngest seafloor is found near continents. B. Seafloor spreading pushes continents. C. Mantle convection causes irreversible slippage. D. Subduction creates the youngest seafloor.

B. Seafloor spreading pushes continents.

Each tectonic plate is composed of A. modified mantle rock. B. crust and uppermost mantle. C. crustal rock. D. either modified mantle rock or crustal rock

B. crust and uppermost mantle.

Volcanoes do not form at which type of convergent plate boundary? A. Oceanic-oceanic boundaries. B. Oceanic-convergent boundaries. C. Continental-continental convergent boundaries.

C. Continental-continental convergent boundaries.

Which of the following lines of evidence supported Wegener's continental drift hypothesis? A. Fit of continents, similar ocean basins, ancient ice sheets. B. Fit of continents, ancient ice sheets, evolution of fish. C. Fit of continents, similar fossils, matched-up rocks. D. Fit of continents, matched-up rocks, east-west polarity

C. Fit of continents, similar fossils, matched-up rocks.

The Himalayan Mountains formed at which type of plate boundary? A. Transform-fault boundary. B. Oceanic-continental convergent boundary. C. Divergent boundary. D. Continental-continental convergent boundary

D. Continental-continental convergent boundary.

How does the seafloor become magnetized? A. Accumulating sediment on the seafloor aligns with Earthʼs magnetic field. B. The seafloor becomes magnetized when the poles reverse. C. When magnetic poles wander slightly around the geographic poles, the seafloor responds by becoming magnetized. D. Magnetite crystals become aligned with Earthʼs magnetic field as new oceanic crust cools from a molten state.

D. Magnetite crystals become aligned with Earthʼs magnetic field as new oceanic crust cools from a molten state.

What are the 3 type of convergent boundaries and the main difference between them? Example:

Oceanic-oceanic convergence - The denser plate descends beneath the other, partial melting of mantle rock generates magma and volcanoes, forms a volcanic island arc. Oceanic-continental convergence - Denser oceanic plate subducts, partial melting of subduction rock, and generates magma, forms continental volcanic arcs Continental-continental - less dense lithosphere does no subduct, produces mountains (himalayas, alps, appalachians), no volcanoes, but could produce earthquakes. PNW

Plate tectonics differ from continental drift in which of the following ways? A. Plate tectonics provides a credible driving force. B. Plate tectonics does not explain the fit between South America and Africa. C. Plate tectonics showed that ancient ice sheets did not exist. D. Plate tectonics showed that Pangaea broke up much later than predicted by continental drift.

Plate tectonics provides a credible driving force