File:Nova Scotia DGJ 5583 (3830611365).jpg
Roughly 200 million years ago Nova Scotia was located in the interior of the super-continent, Pangaea. Movements that began during the Triassic Period were so dramatic they eventually resulted in the break up of Pangaea into North and South America, Africa and the Atlantic Ocean. Today, when the earth's crust moves and shifts, we often witness changes of a similar magnitude caused by the devastating and destructive results of immense earthquakes and tsunamis.
Deep beneath the Earth's crust (the lithosphere: a solid array of plates) is a layer of heated rock known as the asthenosphere. It is heated by the radioactive decay of elements such as uranium, thorium and potassium. This heat causes the ocean floors to continually move, shifting and separating from the center in different directions.
The crustal portions of oceanic plates primarily consist of basalt. As the continents shifted, lava forced to the surface cooled and formed into columnar basalt sea stacks. These columns are usually six-sided, but can feature as few as three or as many as twelve (or more) sides.Dennis G. Jarvis
|
|||
---|---|---|---|
Alternative names |
pseudonym: archer10; Archer10 | ||
Description | photographer | ||
Authority file | 22490717@N02 (photos · photo sets) |