The prevailing ideas of the geology of our planet when our generation was in school was that the position of the continents and ocean basins were fixed in time and place. Continental drift was not accepted. Vertical movement on land produced mountain ranges and the elevator tectonics of the ocean produced submarine canyons which could be subaerially eroded down the continental slope. The floors of the Pacific were assumed to be basalt and the floors of the Atlantic Ocean were of granite. Ocean basins were saucers of great thicknesses of sediment in a motionless abyss. These sediments had been deposited continually throughout all geologic time.