Atlantic Floor Age Diagram

This feature though of tremendous proportions is but the atlantic portion of the world encircling.

Atlantic floor age diagram. Seafloor spreading occurs along mid ocean ridges large mountain ranges rising from the ocean floor. Age of rocks changes from the center to the edges of the ocean floor. This dataset shows the age of the ocean floor along with the labeled tectonic plates and boundaries. Age of the north atlantic ocean basin.

The crust overlies the solidified and uppermost layer of the mantle the crust and the solid mantle layer together constitute oceanic lithosphere. 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. 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. The mid atlantic ridge for instance separates the north american plate from the eurasian plate and the south american plate from the african plate the east pacific rise is a mid ocean ridge that runs through the eastern pacific ocean and separates the pacific plate from the north american.

This image shows the age of rocks on the atlantic ocean seafloor. East and west of the ridge about 12 000 to 18 000 feet 3 700 to 5 500 metres below sea level lie basins that seem to present a relatively even profile but parts of the basin floor are as mountainous as the mid atlantic ridge while other parts are extremely smooth. The following features are shown at example depths to scale though each feature has a considerable range at which it may occur. Consider how the age of rocks is related to the shape of the seafloor you saw in step 3.

To determine the age of the ocean basin divide the distance in centimeters separating the continental shelves by the rate of sea floor spreading for the atlantic ocean basin. Because of this the youngest sea floor can be found along divergent boundaries such as the mid atlantic ocean ridge. This amount of time defines the age of a rock. Oceanic crust is the uppermost layer of the oceanic portion of a tectonic plate it is composed of the upper oceanic crust with pillow lavas and a dike complex and the lower oceanic crust composed of troctolite gabbro and ultramafic cumulates.

In the south atlantic it separates the. 164 million years years show formulas for calculations with units 622 896 000 cm 3 8 cm yr. The spreading however is generally not uniform causing linear features perpendicular to the divergent boundaries. This graphic shows several ocean floor features on a scale from 0 35 000 feet below sea level.

For that geologists date and study continental crust. Therefore seafloor dating isn t that useful for studying plate motions beyond the cretaceous.