This document discusses various features of sea floor morphology including submarine canyons, continental rises, abyssal plains, pelagic sedimentation, reefs, atolls, guyots, seamounts, mid-ocean ridges, fracture zones, trenches, and continental margins. It describes morphological features like rift valleys, pillow basalts, gabbro dikes, axial volcanoes, and hydrothermal vents associated with mid-ocean ridges. It also discusses crustal recycling at trenches and the classification of continental margins as either passive or active.