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An area where the mouth of the river opens into the ocean.


Of the sea, produced by the sea, found in the sea.


Water with no salt content.

brackish water

Slightly salty water.


The measure of the amount of the salts dissolved in seawater.

surface water

Water found on the surface of the earth. Examples: ponds,lakes,etc.

subsurface topography

Formations underground or under water.


Ledge of land or rock under the sea.


A long, narrow steep-sided depression in the seafloor forms when one plate sinks below another.


A long narrow chain of hills or mountains.


Low area on the Earth that became an ocean when rainwater filled the area.


An opening in the Earth.


Loose materials such as rock fragments that have been moved by wind, water, ice, or gravity.

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