The Ocean Basins

Three Major Oceans A B C Atlantic Indian Pacific

Three Major Oceans Atlantic – the shallowest ocean (3.3km average depth) Indian – second shallowest ocean (3.8km average depth) Pacific – the deepest ocean (3.9km average depth)

Small area of the ocean that is partially surrounded by land What is a sea? Small area of the ocean that is partially surrounded by land

Numerous seas – they are all considered part of an ocean The Seven Seas 3 4 1 7 2 5 6 Numerous seas – they are all considered part of an ocean

Exploring our Oceans Oceanography is the study of the physical characteristics, chemical composition and life forms of the ocean.

What are Submersibles? Underwater research vessels The Alvin The Jason

SONAR Important to help map ocean floor Sound Navigation and Ranging

How SONAR works… ocean surface receiver transmitter ocean floor

Differences in the time it takes for the sound waves to leave the boat and then return tell scientists how deep the ocean bottom is.

Features of the Ocean Basins Continental margin: portion of ocean made up of continental crust

Features of the Ocean Basins continental shelf: flat part of continental margin covered by shallow ocean water Formed by changes in sea level Avg depth = 60 m

Features of the Ocean Basins continental slope: boundary between continental crust and oceanic

Features of the Ocean Basins submarine canyons: deep, v-shaped valley that cuts through shelf & slope

Features of the Ocean Basins continental rise: wedge of sediments that separates slope from ocean floor

Features of the Ocean Basins abyssal plain: large flat area on the ocean floor

Features of the Ocean Basins seamount: underwater volcanic mountain (1000m)

Features of the Ocean Basins guyot: a flat-topped submerged seamount

Features of the Ocean Basins trench: deep narrow valleys along the edges of ocean floor Marianas Trench in Pacific ocean is 36,000 ft deep (6mi) – deepest point

Features of the Ocean Basins mid-ocean ridge: mountain range on ocean floor

Features of the Ocean Basins rift valley: deep crevice in between mountain ranges

Features of the Ocean Basins coral reef: limestone structures containing shells of animals that surround volcanic islands