Geological oceanography is the study of Earth beneath the oceans. It involves geochemical, geophysical, sedimentological and paleontological investigations of the ocean floor and coastal margins. Geological oceanography includes exploring the ocean floor and the processes that form its canyons, valleys and mountains . Geological oceanographers research on the sea-floor spreading, plate tectonics, and oceanic circulation and climates. They examine the various ocean features such as rises and ridges, seamounts, trenches, etc. Geological oceanography is one of the broadest fields in the Earth Sciences and contains many subdisciplines, including geophysics and plate tectonics, petrology and sedimentation processes, and micropaleontology and stratigraphy.