In the places where the plates are moving apart magma liquid rock moves up into the cracks and solidifies making a new ocean floor just like cake batter would ooze up through.
Sea floor spreading comic strip.
The oceanic crust is composed of rocks that move away from the ridge as new crust is being formed.
The motivating force for seafloor spreading ridges is tectonic plate pull rather than magma pressure although there is typically significant magma activity at spreading ridges.
The process of sea floor spreading.
See also continental drift a veritable legion of evidence supports the seafloor spreading hypothesis.
Eruptions of molten material magnetic stripes in the rock of the ocean floor and the ages of the rocks themselves.
In 1968 the glomar challenger a deep sea research vessel set out to collect drilling samples from around the world.
The formation of the new crust is due to the rising of the molten material magma from the mantle by convection current.
Students learn about seafloor spreading in class doing a paper strip model of divergent and convergent plate boundaries.
Several types of evidence supported hess s theory of sea floor spreading.
What researchers discovered was that there were ridges found in the center of oceans.
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.
At ridges in the middle of oceans new oceanic crust is created.
Sea floor spreading happens at places where plates are moving away from each other and where the liquid rock from the asthenosphere can come up to the lithosphere.
Further he claimed that continents would be pushed aside by the same forces that cause the ocean to grow.
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.
Spreading rate is the rate at which an ocean basin widens due to seafloor spreading.
They found that the ocean floor was not flat as previously expected.
Evidence for sea floor spreading.
This evidence led scientists to look again at wegener s hypothesis of continental drift.
Spreading rates determine if the ridge is fast intermediate or slow.
The concept of seafloor spreading was put forward by h harry hess an american geologist.
The rate at which new oceanic lithosphere is added to each tectonic plate on either side of a mid ocean ridge is the spreading half rate and is equal to half of the spreading rate.
The concept of sea floor spreading.
He suggested that new sea floor forms at the oceanic ridges and spread outwards from the line of origin.
The seafloor moves and carries continents with it.
Seafloor spreading occurs along mid ocean ridges large mountain ranges rising from the ocean floor.