6.3 Seafloor Spreading

What is the primary cause of the magnetic stripes on the ocean floor?

• Ocean currents

• Seafloor spreading

• Tidal forces

• Wind patterns

Tags

NGSS.HS-ESS1-5

NGSS.HS-ESS2-1

How often do magnetic pole reversals occur?

• Every 10 years

• Every 100 years

• Every few hundred thousand years

• Every million years

How does the age of the seafloor change with distance from the ridge?

• It becomes older

• It becomes younger

• It remains the same

• It fluctuates randomly

Tags

NGSS.HS-ESS1-5

NGSS.HS-ESS2-1

What is the sediment thickness at the ridge axis?

• None

• Thickest

• Moderate

• Variable

What is the pattern of magnetic polarity across the seafloor?

• Normal and reversed

• Only normal

• Only reversed

• Random

Tags

NGSS.HS-ESS1-5

What happens to the seafloor as it moves away from the mid-ocean ridges?

• It becomes progressively older

• It becomes progressively younger

• It remains the same age

• It fluctuates in age

Tags

NGSS.HS-ESS1-5

Which of the following is true about the heat flow at the ridge axis?

• It is the hottest

• It is the coldest

• It is moderate

• It is variable

Tags

NGSS.HS-ESS2-3

What is the relationship between crust thickness and distance from the ridge axis?

• Crust thickness increases with distance

• Crust thickness decreases with distance

• Crust thickness remains constant

• Crust thickness fluctuates randomly

Tags

NGSS.HS-ESS1-5

What is the relationship between rock ages and distance from the ridge axis?

• Rock ages increase with distance

• Rock ages decrease with distance

• Rock ages remain constant

• Rock ages fluctuate randomly

Tags

NGSS.HS-ESS1-5

What hypothesis was created in the early 1960s regarding the seafloor?

• Continental drift hypothesis

• Seafloor spreading hypothesis

• Plate tectonics hypothesis

• Oceanic circulation hypothesis