Name two important dissolved gases in seawater. Use the following chart to indicate how density changes with respect to other parameters. The first one is done for you. See figure 6.16 38. Explain how magnetic reversals are used to support the theory of Plate Tectonics.
Magnetic reversals record the Earth s magnetic field at the time of the rock s formation.
Today, rocks form with a magnetic signal indicating north at our present day magnetic north. In the past, magnetic north has been located at the south pole instead. Hence if new rock forms at ridge crests, then it would record magnetic north at that time. The fact that symmetrical stripes showing magnetic reversals are observed shows that new crust must continually be forming at ridge crests.