Asked in Science
How magnetism in rocks suggest that the continents were once joined?
May 26, 2011 6:53AM
The magnetism in basaltic rock on the ocean floor suggests that the continents have been moving away from each other. The earth regularly undergoes magnetic shifts in which north becomes south and vice versa. As the magma rising through the diverging ocean floor cools into basaltic rock, it takes on the magnetic properties of the earth at that moment. In this way we can tell which way the continents are moving and that they were likely joined in the past. On top of this, the general shape of the continents also suggests this supercontinent as well as the distribution of species.