Oldest Parts Of The Ocean Floor

Newly formed land consisting on a arc shaped island chain is called a.

Oldest parts of the ocean floor. The oldest continental rocks are found in cratons. The oldest oceanic crust in the atlantic ocean is part of the mid atlantic ridge mar the longest mountain range in the world. They could be the oldest known organisms on planet earth. Circle the letter of the sge of the oldest parts of the ocean floor.

The mariana trench the world s deepest submarine de pression is more than 11 000m below sea level in some parts about 7 000m below the mean depth of the ocean floor. However parts of the eastern mediterranean sea are remnants of the much older tethys ocean at about 270 and up to 340 million years old. The mid atlantic ridge is a mid ocean ridge which is a system of underwater mountains formed by tectonic plate movements and is a catalyst for oceanic crust formation. The tectonic plates are constantly in motion and new surfaces are always being created.

This continual motion is evidenced by the occurrence of earthquakes and volcanoes. The oldest large scale oceanic crust is in the west pacific and north west atlantic both are about up to 180 200 million years old. Cratons are therefore always found within continents. The mid atlantic ocean ridge is young ocean floor.

The oldest of all oceanic rocks are. Where an oceanic plate is forced beneath a second plate. Where are the oldest parts of rocks on the ocean floor. The ocean crust then spreads out enlarging the ocean.

The oldest parts of the oceanic crust are found farest from the mid ocean ridges at subduction zones and continental shelves. 180 million years old. The trenches around the edges of the eastern pacific ocean are shallower than are those of the western pacific. Deep ocean drilling and radiometric dating in the late 1960s gave an accurate stratigraphy and precise date of the ocean floor.

The new crust is then pushed away from the ridge as newer crust comes to the surface. New ocean crust is formed at the mid ocean ridges. This is because the oldest sea floor is subducted under other plates and replaces by new surfaces. Some cratons in canada and greenland shelter the oldest continental rocks in the world about 4 billion years old.

100 million year old life forms found on the ocean floor. Energy poor environments is the most interesting part of the. A craton is a stable part of the continental lithosphere which has survived several cycles responsible for the merge and the dislocation of supercontinents. Circl the letter of the description of a subduction zone.