OCEAN BASINS & FEATURES: continental shelves slopes, mid ocean ridges, abyssal plain, ocean trenches, seamounts guyots reading comprehension passages. What hides beneath 70 percent of Earths surface in the deep ocean basins? Students explore continental shelves and slopes, mid ocean ridges and deep ocean trenches, and the vast flat abyssal plain. They uncover submarine volcanoes, seamounts and guyots, oceanic islands and atolls, marine topography importance, and ocean floor mapping techniques r