MEA 200 Lecture 4: L4. Touring Ocean Basins: Marine Provinces
30 Mar 2017
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Document Summary
Measures the vertical distance from the ocean surface to mountains, valleys, plains, and other seafloor features. Sounding is a method of determining the depth of water by lowering a weighted line from a boat or platform to the bottom. Poseidonos made first sounding in 85 bc. The challenger stocked 144 miles of rope for sounding. German ship meteor identified mid-atlantic ridge in 1925. Sea marc (sea mapping and remote characterization) Can be towed behind ship to provide very detailed bathymetric strip map. Measures seafloor features based on gravitational bulges in sea surface. Satellites cannot measure ocean depths directly but, they can measure sea surface height. Over a 2000m seamount, water rises about 2m. Reveals bathymetry where ships have not conducted research. Associated with convergent or transform plate boundaries. Linear islands, banks, and deep basins close to shore. Some of the deepest, flattest parts of earth. Deepest trench mariana trench at 11,022 meters (36,161 ft)
