Explore the Mysteries of the Ocean

Introduction to Oceanography

• The Earth’s surface is 71% water and 29% land, with 140 million miles of water and 58 million miles of land.
• The northern hemisphere has more land than the southern hemisphere, with a 39% land and 61% water distribution compared to 19% land and 81% water.
• An echo sounder is an instrument used to determine the depth of the ocean, while a multibeam has not fully mapped out the ocean due to its vastness and cost.
• The continental margin is the portion of the seafloor adjacent to the continental shelf, slope, and rise, with the continental shelf being a gently sloping submerged portion of the continental margin, the continental slope being a steep gradient that leads to the ocean floor, and the continental rise being a gently rising base.
• An active margin is a narrow, deformed sediment, subducted continental margin, while a passive margin has a continental shelf, slope, and rise.
• Submarine canyons form through turbidity currents, while atolls are remains of a volcanic peak covered with coral.
• Seamounts are isolated volcanic peaks that rise at least 3,000 ft above the ocean floor, while guyots are submerged flat-topped seamounts, and abyssal plains are deep, flat sea floors.
• Terrigenous sediments are derived from terrestrial weathering and erosion, biogenous sediments consist of material of marine organic origin, and hydrogenous sediments crystallize from seawater.
• Minerals obtained from the sea include salt, halite, sodium chloride, and gypsum, with seawater evaporating as the source.
• The ocean’s salinity is 3.5% or 35 parts per thousand, affected by rain, snowfall, river discharge, evaporation, formation of sea ice, volcanic eruptions, and river runoff.
• Water density affects positioning in the ocean, with dense water sinking and less dense water rising due to convection.
• The thermocline is a layer of water in which rapid temperature changes happen vertically, while the pycnocline is a layer of water in which there is a rapid change with depth.

How well do you know about the ocean? Take this quiz on Introduction to Oceanography and test your knowledge on the Earth's vast water bodies. From the continental margin to the thermocline, this quiz covers various topics including ocean depths, sediments, and salinity. Challenge yourself with questions on oceanic instruments, formations, and minerals, and discover fascinating facts about the marine world. Take the quiz and dive into the depths of oceanography!