1. Sea Floor spreading and Subduction

2.  The process by which new ocean lithosphere is created as the older rock material is pulled away.

3.  Takes place where plate edges meet. Most often underneath the ocean  Molten rock (magma) spurts up between the plates.  As the magma is cooled by the ocean water it forms new crust.  This new crust creates ocean ridges

4. This process keeps repeating so new crust is constantly being formed The crust increases in age the further it is from the ocean ridge

6. Magma contains magnetic minerals These magnetic minerals align with the magnetic field of the Earth – they move toward the north pole

7.  The (magnetic)North and South pole have switched places many times in Earth’s history  Switching places is called “magnetic reversal”  So the magnetic minerals have created bands or stripes in the crust

8.  Two plates come apart in the ocean  Magma rises to fill in the gap and when it cools it forms a ridge (extra rock crust)  The extra weight of the ridge (extra rock crust) puts pressure on the asthenosphere causing magma to rise again

9.  Rift – is the area of separating plates  Rift valley – is the valley that forms between the ridges  Ridge - is the mountain that is formed by the build up of cooled magma

13.  As the ridges push out new crust the old crust is pulled back down into the mantle.  A slab pull is when the plates are pulled down into the mantle.

17.  Trench – is a ditch like feature formed by subduction  Composite Volcanoes

18.  http://www.pmel.noaa.gov/vents/nemo/educ ation/images/seafloor_spreading.jpg http://www.pmel.noaa.gov/vents/nemo/educ ation/images/seafloor_spreading.jpg  http://www.womenoceanographers.org/Cont ent/Profiles/MelanieSummit/images/LearnM ore1.jpg http://www.womenoceanographers.org/Cont ent/Profiles/MelanieSummit/images/LearnM ore1.jpg  http://www.pmel.noaa.gov/vents/nemo/educ ation/images/seafloor_spreading.jpg http://www.pmel.noaa.gov/vents/nemo/educ ation/images/seafloor_spreading.jpg  http://www.answersingenesis.org/assets/ima ges/articles/am/v2/n2/figure-2-c.jpg http://www.answersingenesis.org/assets/ima ges/articles/am/v2/n2/figure-2-c.jpg