icelands volcanos
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Iceland, the land of ice and fire, is a true paradise for volcanologists. In few places on earth, geology and human history are so closely connected to volcanism as on Iceland. The island owns its existence to a large volcanic hot spot
sitting on a mid-oceanic ridge, a unique setting. The plate boundary between the American and Eurasian tectonic plates crosses Iceland from south to North and the spreading process can be directly measured and observed on land. On average, Iceland experiences a major volcanic event once every 5 years. Since the Middle Ages, a third of all the lava that has covered the earth's surface has erupted in Iceland. However, according to a recent geological hypothesis, this estimate does not include submarine eruptions, which are much more extensive than those on the land surface.Where plates meet, they can rub against each other as they slide in opposite directions; they can collide head-on in a stalemate, pushing each other up or down like two fighting rams; or one might win out and push the other one beneath it. Sometimes, they only move away from each other, releasing pressure and exposing the lava sea between them. This allows the lava to stream to the surface, where it cools down and forms new land. When this happens, the area of separation is called a "constructive junction," and this is precisely what is happening in Iceland. |