These age data also allow the rate of seafloor spreading to be determined and they show that rates.
The sea floor spreads at subduction zones.
When oceanic plates diverge tensional stress causes fractures to occur in the lithosphere.
Seafloor spreading helps to explain continental drift in the theory of plate tectonics.
Why is the atlantic ocean expanding.
As upwelling of magma continues the plates continue to diverge a process known as seafloor spreading 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.
As a result the atlantic basin is expanding at about 0 5 to 4 inches a year.
The denser lithospheric material then melts back into the earth s mantle.
There aren t many subduction zones.
Because there is more seafloor spreading than subduction.
The motivating force for seafloor spreading ridges is tectonic plate slab pull at subduction zones rather than magma pressure although there is typically.
At subduction zones the edge of the denser plate subducts or slides beneath the less dense one.
Basic outline of sea floor spreading that leads to ocean crust diving beneath continental crust.
Since there are minimal subduction zones in the atlantic very few older plates are subducted when spreading occurs.
Some fundamental geologic processes like earthquakes and landforms like volcanoes result from.
The rising and spreading of crust at mors and the sinking of crust at subduction zone is what moves the continents.
Subduction happens where tectonic plates crash into each other instead of spreading apart.
This idea played a pivotal role in the development of the theory of plate tectonics which revolutionized geologic thought during the last quarter of the 20th century.
Trenches accretionary wedges prisms and volcanic or island arcs are key surface features produced by subduction.
Seafloor spreading is just one part of plate tectonics.
The atlantic is home to the mid atlantic ridge a mountain range that extends for about 10 000 miles and is the site of seafloor spreading.
Most such faults are found in oceanic crust where they accommodate the lateral offset between segments of divergent boundaries forming a zigzag.
Subduction is one of the two major processes of plate tectonics the other being seafloor spreading.
A subduction zone is the entire area of subduction between the trench and the volcanic arc.
