How does sea-floor spreading account for the age of sea floor?
The sea floor can only be so old. The sea floor is constantly spreading and creating a new floor. In the middle of the Atlantic, a ridge of volcanic mountains that diverge (spread apart) exposes lava. This lava is the new sea floor. As the the floor moves apart it is subducted underneath continents, therefore the ocean floor can only be so old. I believe its maximum age is about 1.8 million years old. There is a lot of information on this on the web. I gave a very basic answer. Look up the mid ocean ridge and how its related to ocean floor age. I hope this helps!
