Sea-floor Spreading

Question 1

The East Pacific RIse is just one part of the…

Answer 1

Mid-ocean ridge

Question 2

What is the Mid-ocean ridge?

Answer 2

Is the longest chain of mountains in the world

Question 3

What device is used to map the ocean floor?

Answer 3

Sonars

Question 4

What is a sonar?

Answer 4

A sonar is a device that bounces sound waves under water and then records the echoes.

Question 5

Who uses sonars?

Answer 5

Ships and submarines

Question 6

How do sonars work?

Answer 6

Sonars work by sending sound waves and measuring how long it takes to the echoe to return.

Question 7

If the water is shallow?

Answer 7

If the water is shallow the sound waves that reflect on the bottom of the sea will return faster.

Question 8

If the water is depeer?

Answer 8

If the water is depeer the sound waves take longer to travel at the bottom and back.

Question 9

What are the evidence from sea-floor spreading?

Answer 9

Evidence of molten material
Evidence of magnetic stripes
Evidence of dirilliing samples

Question 10

What is deep-ocean trenches

Answer 10

Is a water canyon that forms when the oceanic crust bends downward.

Question 11

What is subduction?

Answer 11

the sideways and downward movement of the edge of a plate of the earth’s crust into the mantle