Grade 9 Social Studies: Oceans & Life

Ocean system

The connected ocean environment, including water, the ocean floor, living things, and movements.

Samudra

A commonly used Indian term for the ocean, significant in stories and rituals.

Human–ocean connection

The ways oceans affect people and how people use and manage oceans.

Ocean relief

The different landforms found on the ocean floor (also called submarine relief), such as underwater mountains, valleys, plains, plateaus, and deep trenches.

Continental shelf

The shallow, submerged edge of a continent that is rich in marine life and may contain resources such as oil and gas.

Continental slope

The steep slope that marks the true edge of a continent.

Continental rise

A gently sloping area of accumulated sediments situated at the foot of the continental slope.

Abyssal plain

A vast, flat, and deep part of the ocean floor.

Mid-ocean ridge

A long underwater mountain range formed by volcanic activity.

Ocean trench

A long, narrow, and very deep depression in the ocean floor.

Seamount

An underwater mountain, usually volcanic, that rises from the ocean floor but does not reach the sea surface.

Guyot

A flat-topped underwater mountain, usually an old seamount whose top was eroded and later submerged.

Submarine canyon

A deep valley-like feature cut into the continental shelf or slope.

Rift valley

A long depression that can form along the crest of a mid-ocean ridge.

Mariana Trench

The deepest place on Earth, located in the Pacific Ocean.