Oceans

Approximately what percentage of Earth's surface is covered by oceans?

• 40%
• 50%
• 60%
• 70%

Which ocean basin is the largest?

• the Atlantic
• the Indian
• the Pacific
• the Arctic

The use of sound waves to determine  the depth of the ocean is called...

• submarine sounding
• sonar
• satellite altimetry
• submersible sounding

The gently sloping  submerged surface that extends from the shore towards the ocean basin is

• shelf
• slope
• rise
• margin

Important mineral deposits, including oil and natural gas, are associated with

• the ocean basin floor
• the continental shelf
• abyssal plains
• the continental rise

What could gas hydrates be used for?

• as a landfill
• to make concrete
• as a source of energy
• as a source of cobalt and copper

What is label one on the diagram?

• continental shelf
• continental rise
• abyssal plain
•  deep ocean trench

The most abundant salt in seawater is

• calcium chloride
• magnesium chloride
• sodium chloride
• sodium chloride

Which process does NOT lead to a decrease in the salinity of water?

• runoff from land
• precipitation
• sea ice melting
• evaporation

Which term refers to a rapid change of temperature with increasing depth of the ocean?

• pycnocline
• thermocline
• abyssalocline
• isothermal cline