6.2 The Ocean Floor

Question 1

Abyssal plain

Answer 1

A very level area of the ocean floor, found between the continental rise and mid-ocean ridges.

Question 2

Atoll

Answer 2

A low-lying, ring-shaped island or group of islands composed of coral reefs and that surrounds a central lagoon.

Question 3

Continental margin

Answer 3

The edge of a continent, including the continental shelf, continental slope, and continental rise.

Question 4

Continental shelf

Answer 4

The submerged, usually gently-sloping extension of the continent extending from the shoreline to the continental slope.

Question 5

Continental slope

Answer 5

The steepest part of the continental margin, sloping down from the continental shelf to the continental rise.

Question 6

Continental rise

Answer 6

The gently-sloping part of the seafloor along the base of the continental slope.

Question 7

Deep-ocean trench

Answer 7

The deepest parts of the oceans, formed where one tectonic plate subducts beneath another plate.

Question 8

Guyot

Answer 8

A flat-topped seamount.

Question 9

Hydrothermal vent

Answer 9

A hot spring on the floor of the ocean or a lake.

Question 10

Manganese nodule

Answer 10

A rock that is about the size and shape of a potato that lies scattered in large numbers at many places on the ocean floor.

Question 11

Mid-Ocean ridge

Answer 11

A continuous mountain range that runs through all of the oceans. The rift at the summit of a mid-ocean ridge is the site of seafloor spreading.

Question 12

Seamount

Answer 12

Isolated volcanic mountains on the seafloor.