If the water in the oceans were emptied . Plate tectonics: outermost portion of the earth is composed of thin, rigid plates that move horizontally with respect to one another, the interactions between these plates as they move build features of. Videos: https://www. youtube. com/watch?v=zocutif0cqy (ice age continental drift) https://www. youtube. com/watch?v=kwfngatxuji (minute earth plate tectonics) Ocean provinces: continental margin, deep-ocean basins, mid-ocean ridge. Continental margin: continental shelf almost flat and featureless, shelf break, continental slope increase in slope angle, continental rise transition zone, canyons v-shaped deep submarine valleys, passive vs active margins. Mid-ocean ridge: covers about 23% of earth"s surface, 2500 m above seafloor, 1000 km wide, rift valley oceanic ridge vs oceanic rise, pillow lavas smooth, rounded lobes of rock, hydrothermal vents water entering cracks, transform faults. Videos: https://www. youtube. com/watch?v=hmmlspnozms (volcanic activity) https://www. youtube. com/watch?v=ddiuuuy0l9c (pillow lava) https://www. youtube. com/watch?v=rtr6ggdwcjk (hydrothermal vents) Problems: determining when the weight has hit the bottom (especially in deep water).