Hey guys! I had an awesome time visiting my family, and seeing the San Andreas Fault, but it was waaayy to warm in Cali. I really wanna go somewhere cold, but not to Antarctician-ish. My mom suggested Iceland, but there was a volcano there.... O.M.G. A VOCANO! That country is perfect for me! And I hear there is a divergent boundary in Iceland. Exciting! And I can go get some uber cute mittens! (UGG was out when I went to New Zealand...)
A divergent boundary is when two tectonic plates move apart, resulting in volcanic material being
brought to the surface. This usually occurs in the ocean creating new sea-floor.
But when there is an occasional continental case....
When a divergent boundary occurs beneath a thick continental plate, the pull-apart is not strong and large enough to make a clean break through the thick material. As the two plates pull apart, normal faults develop on both sides of the rift and the central blocks slide downwards. Earthquakes occur as a result of this fracturing and movement. Early in the rift valley-forming process, streams and rivers will flow into the sinking rift valley to form a long linear lake. As the rift grows deeper it might drop below sea level allowing ocean waters to flow in. This will produce a narrow, shallow sea within the rift. This rift can then grow deeper and wider. If rifting continues a new ocean basin could be produced.
Iceland is located on a divergent boundary. It is one of only a few places on our Earth where we can see a divergent boundary above sea level! Why is this? The definition of a divergent boundary tells us that volcanic material is brought to the surface on a regular basis. It happens so often that the divergent boundary has formed its own volcanic island! This hot spot of volcanic activity has formed many volcanoes and caused many earthquakes!
http://www.platetectonics.com/book/page_5.asp
The North American and Eurasian plates are currently moving apart at a rate of 2 centimeters per year. This means that Canada is getting further and further away from Europe every year! (I hope that doesn't affect the cost of plane tickets! I use that extra money for clothing!)
The Mid-Atlantic Ridge is a divergent boundary between the North American and Eurasian Plates. As North America moves west, and Eurasia east, new crust is created on both sides of the divergent boundary. While the creation of new crust adds mass to Iceland on both sides of the boundary, it also creates a rift along the boundary. Iceland will break into two separate land masses at some point in the future, and the Atlantic waters will eventually rush in to fill the widening and deepening space created between.
http://upload.wikimedia.org/wikipedia/commons/a/a4/Bridge_across_continents_iceland.jpg
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