Earth’s Water – The Ocean
When viewed from space, the Earth looks like a giant blue ball. It’s sometimes called the ‘blue marble’.
The Earth’s blue color is due to about 75 percent of its surface being covered in water. Most of the water on Earth is in the ocean. There is also water in rivers, lakes and under the ground.
The ocean is the large body of salt water that covers more than three-quarters of the Earth’s surface. The salt in the ocean’s water comes from the chemical erosion of rocks on land by water. As water erodes rocks, salts from the rocks are carried to streams and rivers and eventually to the ocean. Some salt also comes from openings on the ocean floor.
The ocean is usually shallow close to land. On beaches and coral reefs, the water is typically only a few meters deep. Further out to sea, the ocean can reach depths of over 10 kilometers.
Just like on land, the ocean floor has a variety of features. There are deep ocean trenches, abyssal plains and underwater volcanoes.
Related Printables.
Earth’s Landforms
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_01.small_.jpg)
Comprehension – Earth’s Landforms
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_02.small_.jpg)
Local Land and Water Features
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_03.small_.jpg)
Modeling the Earth’s Features
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_04.small_.jpg)
The Ocean
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_05.small_.jpg)
Earth’s Fresh Water
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_06.small_.jpg)
Using Maps
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_07.small_.jpg)
Map Features
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_08.small_.jpg)
Map Patterns in the United States
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_09.small_.jpg)
Comprehension – Ocean Patterns
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_10.small_.jpg)
Observing Ocean Patterns
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_11.small_.jpg)
Review – Mapping the Earth’s Surface
![](https://ngscience.com/wp-content/uploads/4-NGScience-Mapping-the-Earths-Surface_12.small_.jpg)
Assessment Pack
• printable PDF
• answer key
• marking guide