Hydrographic Relief GlobeHydrographic Relief Globe 30. 5 cm SOLD BY: EachA 12" diameter plastic globe portrays land, water and submarine areas in accurate 3 D relief. Features such as continents, islands, plateaus, straits, bays, and channels can be quickly identified. Through the ocean surface, represented by clear plastic, students can see the continental shelf, mountain chains, sea mounts, trenches, basins and plains that comprise the ocean floor. All major continents,