Interactive Animation of Seafloor Spreading and Magnetic Field Reversals
Interactive Animation of Seafloor Spreading and Magnetic Field Reversals
Earth's magnetic field reverses itself from time to time; North becomes South and South becomes North. Lava that cools and becomes rock at a given time in Earth's history stores a record of our planet's magnetic polarity at the time of the rock's formation. Rocks on the seafloor on either side of a mid-ocean spreading ridge preserve a record of the Earth's magnetic field over time. The discovery of this phenomenon was an important bit of evidence that helped confirm the theory of plate tectonics. The interactive animation below illustrates this concept. Drag the compass, which represents a magnetometer, to the right and left. Can you find places where the magnetism of the rocks reverses? This section of seafloor is in the North Atlantic Ocean near Iceland. The rate of plate movement in this area is about 25 millimeters (1 inch) per year, or about 25 km (16 miles) every million years. Can you determine when the field reversals occurred? Click the "Distance" checkbox to view a distance scale. Click the "Age" checkbox to see the age of the seafloor on either side of the ridge. On this section of the seafloor, the history of Earth's magnetic field that is revealed includes the following periods: -Brunhes normal - present time to 730 thousand years ago -Matuyama reverse - 0.73 to 2.48 million years ago (ma) -Gauss normal - 2.48 to 3.40 ma -Gilbert reverse - 3.40 to 5.3 ma
About BeeGames social
Playground and Play together are the BeeGames social layer — so you're never just playing alone.
What is a Playground?
Your Playground is your own personal game homepage. Pin the games you love, give it a name and a short bio, then make it public to share your personal arcade with anyone.
How do I use my Playground?
On any game page, tap “Playground” to pin that game. Head to My Playground to edit its name, bio and layout, then share your public link with friends.
What is Play together?
Play together lets you co-play the same game with friends in real time. Open a game room and everyone can play side by side while chatting in the room — like crowding around one screen, online.
How do I play with friends?
Tap “Play together” on a game page, pick a public room or a private one with a password, then share the room link with friends. You can also browse and join open rooms from the Lobby.