Image: Mercator Projection of globe

Relief courtesy of National Geophysical Data Center, NOAA

Download this activity as a PDF.

Earth’s continental landscapes—mountains, valleys, canyons—are familiar to students everywhere. But many students do not realize that ocean floor landscapes are equally dramatic and varied.

In the map to the right, which uses a technique called "choropleth mapping" to show depth, areas of darkest blue are the deepest parts of the oceans, while areas of light blue are relatively shallow.

Oceans cover approximately 71% of Earth’s surface. Their average depth is 16,000 feet (4,880 meters). But the ocean floor is marked by mountain chains called "mid-ocean ridges" and deep valleys called "trenches."

Mapping the Ocean Floor Landscape

Provide students with blank world maps.

Download a World Outline Map

Have students use National Geographic ocean floor maps to locate and label the following ocean floor features on their outline maps.

Features on the Ocean Floor

Pacific Ocean – Mariana Trench (-35, 827 ft/ -10,920 m.) Japan Trench (-34,318 ft/-10,375 m.); East Pacific Rise (under water ridge)

Atlantic Ocean – Puerto Rico Trench (-28,231 ft./-8,605 m.); Brazil Basin (-20,898 ft./-6,310 m.); Mid-Atlantic Ridge

Indian Ocean – Java Trench (-23,812 ft./-7,258 m.); Mid-Indian Ocean Ridge

Arctic Ocean – Fram Basin (-15,305 ft./-4,665 m.); Lomonosov Ridge

Extension Activity

In 2000, the International Hydrographic Organization identified a fifth division in Earth’s oceans—sometimes called the Southern Ocean. This ocean area, which extends from the shores of Antarctica to 60º South latitude, is not universally recognized as a separate ocean. Have students research the so-called Southern Ocean and identify its unique characteristics.

About the National Geographic Bee

Each year thousands of schools in the United States participate in the National Geographic Bee using materials prepared by the National Geographic Society. The contest is designed to inspire students to be curious about the world. Schools with students in grades four through eight are eligible for this entertaining and challenging competition.

Registration for the 2015 National Geographic Bee has ended. Schools can register for the next competition on August 18, 2015. Early bird registration starts at $100 per school. Vouchers will be available for qualifying schools. Sign up here to receive a reminder email that early bird registration is starting.

Utah State Winner

Gauri Garg, Utah State Bee Champion, was asked to select one superpower, and one global and community issue to solve. She’d use her special powers to end pollution by converting pollutants and educating the public about hazardous vehicle emissions.

How to Help

  • Photo: Geo Bee Winners

    Fund a School

    Donations help fund schools to participate in the National Geographic Bee.

Student Activities

Teachers can use these activities in the classroom to prepare students for the bee!

  • Photo: Map of the world showing areas of freshwater

    Geo-Scavenger Hunt

    Simply memorizing terms and place locations can be tedious and even boring. One solution is to make the task fun with an atlas-based scavenger game.

  • Photo: Map of languages

    Exploring Diffusion

    The movement of people, goods, or ideas from one place to another is a process known as diffusion, which plays an important role in shaping the characteristics of where we live.

  • Photo: Infared satellite image of hurricane Rita

    Tracking Violent Storms

    Springtime brings the possibility of extreme weather, including violent thunderstorms and tornadoes.

See More From the Study Corner »