03:21
Beneath the Surface: Ocean's Horizontal Layers, The
The area beneath the surface of the ocean is laid out in discrete zones and layers. These provide a convenient framework within which to analyze ocean structure.
02:41
Over the Edge: Undersea Volcanic and Tectonic Activity
For large stretches the deep ocean basin is flat. But seamounts, guyots, island arcs and trenches, all of which result at least in part from tectonic activity, break up the sameness.