It is a theory that the lithosphere is broken into plate, which are much like segments of a cracked shell on a boiled egg. These segments move more relative to one another while sliding on the underlying astenophere.

1. astenophere is a soft upper mantle underlying the lithosphere.

2. lithosphere means rock. The particles of this rock are the crust, the skin of the earth, and the mantle, which is the largest concentrate zone of the earth.

The entire process that is observed takes place along plate boundaries.

1. plate boundaries are where two plates are pulling away from each other sliding past each other, or moving toward each other.

Another aspect of plate tectonics is diverging boundaries that exist where plates are moving apart. This process coincides with the crest of mid-oceanic ridges.

1. mid-oceanic ridges is higher than ocean floors because the upward flow of mantle material pushes the lithosphere upward because the rocks are less dense.

In these mid-oceanic ridges, cracks develop along the ridge crest forming magma chambers underlying the astenophere. The magma then squeezes into fissures, or cracks, in the lithosphere. Some magma erupts along ridge crest. A continuous pulling of the ridge crest develop new crack, and this filling process is repeated, making plate tectonics continuous.

In Geology 1001 we have been discussing plate tectonics .

For more information on tectonics click here.
 
 

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