ES-4.4-Divergent-Plate-Boundaries-and-Seafloor-Spreading

Multiple Choice

Bellringer:

Which crust is older, continental or oceanic?

• Continental crust is older
• Oceanic crust is older
• They are the same age
• It depends on the location

Multiple Choice

Why are divergent plate boundaries and seafloor spreading significant for understanding Earth's geological features?

• They explain the formation of mountains on continents

• They are responsible for the creation of new oceanic crust and the longest topographic features on Earth

• They cause the destruction of oceanic crust

• They only occur on land

Multiple Choice

Which of the following statements about the global oceanic ridge system is correct?

• It represents 20% of Earth's surface and exceeds 70,000 kilometers in length.

• It is only found in the Atlantic Ocean and is less than 10,000 kilometers long.

• It is the deepest part of the ocean and is not connected to any ocean basins.

• It is formed only by volcanic eruptions and does not rise above adjacent ocean basins.

Open Ended

Explain how tensional forces contribute to the formation of rift valleys along oceanic ridges.

Multiple Select

Which of the following are thermal effects on oceanic lithosphere as it moves away from the ridge axis?

• New lithosphere forms and is less dense.

• Lithosphere cools, contracts, and increases in density.

• Temperature stabilizes after about 80 million years.

• Lithosphere becomes thinner as it moves away from the ridge.

Multiple Choice

What evidence supports the idea that the East African Rift is an example of continental rifting in action?

• Presence of large volcanic mountains like Mount Kilimanjaro and Mount Kenya

• Formation of deep ocean trenches

• Absence of any volcanic activity

• Stable and unchanging landforms

Multiple Choice

What is the main process that occurs at divergent plate boundaries?

• Seafloor spreading

• Subduction

• Mountain formation

• Earthquake generation