The Sea Floor Spreads At Subduction Zones

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.

Some fundamental geologic processes like earthquakes and landforms like volcanoes result from. 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. Because there is more seafloor spreading than subduction. Subduction happens where tectonic plates crash into each other instead of spreading apart.

As a result the atlantic basin is expanding at about 0 5 to 4 inches a year. The rising and spreading of crust at mors and the sinking of crust at subduction zone is what moves the continents. Basic outline of sea floor spreading that leads to ocean crust diving beneath continental crust. There aren t many subduction zones.

The motivating force for seafloor spreading ridges is tectonic plate slab pull at subduction zones rather than magma pressure although there is typically. Seafloor spreading helps to explain continental drift in the theory of plate tectonics. 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. It ends abruptly where it connects to another plate boundary either another transform a spreading ridge or a subduction zone.

A transform fault or transform boundary is a fault along a plate boundary where the motion is predominantly horizontal. Most such faults are found in oceanic crust where they accommodate the lateral offset between segments of divergent boundaries forming a zigzag. When oceanic plates diverge tensional stress causes fractures to occur in the lithosphere. The denser lithospheric material then melts back into the earth s mantle.

Seafloor spreading theory that oceanic crust forms along submarine mountain zones known collectively as the mid ocean ridge system and spreads out laterally away from them. Since there are minimal subduction zones in the atlantic very few older plates are subducted when spreading occurs. A subduction zone is the entire area of subduction between the trench and the volcanic arc. Subduction is one of the two major processes of plate tectonics the other being seafloor spreading.

Why is the atlantic ocean expanding. At subduction zones the edge of the denser plate subducts or slides beneath the less dense one.