Development Of The Ocean Floor

Wherever continents are bordered by deep sea trench systems as in the pacific ocean the ocean floor is plunged downward underthrusting the continents and ultimately reentering and dissolving in earth s mantle from which it had originated.

Development of the ocean floor. Basalt the once molten rock that makes up most new oceanic crust is a fairly magnetic substance and scientists began using magnetometers to measure the magnetism of the ocean floor in the 1950s. Until the development of sonar we knew very little about the ocean floor. The magnetism of mid ocean ridges helped scientists first identify the process of seafloor spreading in the early 20th century. Scientific research submersibles have explored the ocean s deepest trenches but most are designed to reach only the ocean floor.

It is believed that continental rocks formed 3 billion years ago however the sediments samples from the ocean floor are found to be not exceeding 200 million years old. The landscape of the ocean floor is much like what you see on land just way more dramatic and without all that life. The deep ocean is dark very cold and has tremendous pressure from the overlying water. You ll see underwater mountains called seamounts cliffs trenches and.

The outer rocky layer of the earth includes about a dozen large sections called tectonic plates that are arranged like a spherical jig saw puzzle floating on top of the earth s hot flowing mantle. Echo sounder in regions of heavy precipitation the salinity of the surface water is. Our picture of the ocean floor greatly sharpened after world war i 1914 18 when echo sounding devices primitive sonar systems began to measure ocean depth by recording the time it took for a sound signal commonly an electrically generated ping from the ship to bounce off the ocean floor and return. The features mapped on the ocean floor disproved continental drift.

The development of this instrument greatly enhanced our knowledge of the ocean floor. Most plate boundaries are under the ocean. All this evidence both from the ocean floor and from the continental margins made it clear around 1965 that continental drift was feasible and the theory of plate tectonics which was defined in a series of papers between 1965 and 1967 was born with all its extraordinary explanatory and predictive power. See also continental drift.

What they discovered was that the magnetism of the ocean floor around mid ocean ridges was divided into matching stripes on either side of the ridge. The ocean floor had tracks from the continents. Bathymetry the shape of the ocean floor is largely a result of a process called plate tectonics.