Relief courtesy of National Geophysical Data Center, NOAA
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.
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
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.
Bring the exciting competition of the National Geographic Bee to your school! Take advantage of the early-bird registration; the $100 fee includes contest materials and prizes. Schools with financial need can apply for discounts here.
Test Your Geography IQ
Can you answer these video questions from the 2015 National Geographic Bee Championship? Questions from Pharrell Williams, Wynton Marsalis, and National Geographic Explorer Fredrik Hiebert will test your knowledge of the world.
How to Help
Donations help fund schools to participate in the National Geographic Bee.
Teachers can use these activities in the classroom to prepare students for the bee!
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.
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.
Springtime brings the possibility of extreme weather, including violent thunderstorms and tornadoes.