Ocean Ridges and Trenches

Sea-floor Spreading is the theory that new sea floor is added at ________________

• Mid-ocean trenches

• Deep ocean trenches

• Continents

Tags

NGSS.MS-ESS2-2

NGSS.MS-ESS2-3

What are Mid-Ocean Ridges?

• A chain of underwater waterfalls

• A chain of underwater volcanos

• A deep canyon in the ocean floor

Tags

NGSS.MS-ESS2-3

The OLDEST seafloor is located? 

• Closest to the mid-ocean ridge
• Farthest from the mid-ocean ridge

Tags

NGSS.MS-ESS1-4

True or false : Deep-Ocean Trenches are underwater canyons?

• False
• True

What is one piece of evidence of seafloor spreading?

• scientist found animals at the bottom of the sea

• expanding continents

• scientist found pillow shaped rocks (made from lava)

Tags

NGSS.MS-ESS2-3

Another piece of evidence for sea-floor spreading is the age of rocks. Choose the true statement about this evidence below:

• The age of the oceanic crust gets older the further you go from a mid-ocean ridge.

• The age of the oceanic crust gets younger the further you go from a mid-ocean ridge.

• The age of the oceanic crust is the exactly the same no matter where you go.

Magnetic stripes in the oceanic crust are another piece of evidence that prove the ocean floor....

• Was made at the same time

• Has different ages throughout the floor (newer crust next to MOR)

• Changes the magnetic poles of the earth

The oceanic crust is pushed aside on both sides of the 

• Continent's edge
• Deep-ocean trench
• Mid-ocean ridge

Tags

NGSS.MS-ESS2-3

The oceanic crust _________ when it reaches the continental crust.

• subducts (sinks)

• rises

• expands

Tags

NGSS.MS-ESS2-3

New crust is always formed at the...

• mid-ocean ridge
• deep-ocean trench
• asthenosphere