Age Ocean Floor

The ionic growing earth ige posits the same 8 elements that started the earth heated the planet for the first 3 3 5 billion years of its existence see ige fig.

Age ocean floor. The magnetism of mid ocean ridges helped scientists first identify the process of seafloor spreading in the early 20th century. Therefore seafloor dating isn t that useful for studying plate motions beyond the cretaceous. February 4 2019 eugene ellis. Seabed contains several hundred years worth of cobalt and nickel.

The crust overlies the solidified and uppermost layer of the mantle the crust and the solid mantle layer together constitute oceanic lithosphere. Contours of 20 million years are available as a layer that is currently set to invisible. Sio reference series 93 30 scripps institution of oceanography. The data is from four companion digital models of the age age uncertainty spreading rates and spreading asymmetries of the world s ocean basins.

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 what they discovered was that the magnetism of the ocean floor around. For that geologists date and study continental crust. This dataset shows the age of the ocean floor along with the labeled tectonic plates and boundaries. The survey data was used to create three dimensional relief maps of the ocean floor and by 1953 american oceanic cartographer marie tharp had created the first of several maps that revealed the presence of an underwater mountain range.

The arrival of water 1400 mya solidified the molten crust and by 1200 mya submerged. In recent years satellite images show a very clear mapping of the seabed and are used extensively in the study and exploration of the ocean floor. The following features are shown at example depths to scale though each feature has a considerable range at which it may occur. The data are described in a data and analysis note in the journal of geophysical research 1997 entitled digital isochrons of the world s ocean floor.

The process that continually adds new material to the ocean floor is seafloor spreading and the continental slope. Samples collected from the ocean floor show that the age of oceanic crust increases with distance from the spreading centre important evidence in favour of this process. These age data also allow the rate of seafloor spreading to be determined and they show that rates vary from about 0 1 cm read more. A digital age map of the ocean floor.

Because of this correlation between age and subduction potential very little ocean floor is older than 125 million years and almost none of it is older than 200 million years. Continental shelf 300 feet continental slope 300 10 000 feet abyssal plain 10 000 feet abyssal hill 3 000 feet up from the abyssal plain seamount 6 000 feet. Shortly after the conclusion of world war ii sonar equipped vessels crisscrossed the oceans collecting ocean depth profiles of the seafloor beneath them.