Iceland - Geography
Iceland is a land of great contrasts, especially in its physical geography and geology. Glaciers and volcanoes abound in this geologically dynamic land that sits astride the Mid-Atlantic Ridge; 11 percent of the land is covered with glaciers, and more than 150 volcanic eruptions have been documented since settlement.
Iceland is an island in the Atlantic Ocean, located near the Arctic Circle, between Greenland and Norway. An island of 103.000 km2 (40,000 square miles), it is about the same size as Hungary and Portugal, or Kentucky and Virginia. Iceland is the second largest island in Europe, following Great Britain, and the 18th largest island in the world. The coastline is 4,970 km, and Iceland maintains a 200 nautical-miles exclusive economic zone. It takes approximately five hours to fly from New York to Reykjavík, and three hours from London.
Iceland’s highest peak is Hvannadalshnjúkur, standing 2,119 metres (6852 ft) over sea level. and over 11 percent of the country is covered by glaciers, including Vatnajökull, the largest in Europe. Its land mass comprises glaciers (12,000 km2), lava (11,000 km2), sand (4,000 km2), water (3,000 km2) and pasture (1,000 km2).
Iceland is the least populated country in Europe. Almost 80% of the country is uninhabited, and much of its terrain consists of plateaux, mountain peaks, and fertile lowlands. There are many long, deep fjords and glaciers, including Europe’s largest, Vatnajökull. Its landscape’s is characterized by waterfalls, geysers, volcanoes, black sand beaches and otherworldly steaming lava fields.
Iceland is one of the youngest landmasses on the planet, and consequently home to some of the world’s most active volcanoes. The island owes its existence to a large volcanic fissure in the Mid-Atlantic Ridge, where the Eurasian and American tectonic plates meet. Even today, the country is growing by about 5 cm per year, as it splits wider at the points where two tectonic plates meet.
Iceland sits astride the middle of the Mid-Atlantic Ridge, which is an integral part of the global mid-oceanic ridge system. This ridge is a 40,000 km crack in the ocean floor caused by the separation of the North American and Eurasian tectonic plates. The Mid-Atlantic Ridge has made Iceland into a landmass between the submarine Reykjanes Ridge to the southwest and the Kolbeinsey Ridge to the north, and has been active during the last 20-25 million years, broadly coinciding with the time-span of active volcanism in Iceland.
Accordingly, the western part of Iceland, to the west of the volcanic zones, belongs to the North American plate and the eastern part to the Eurasian plate. 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.
Volcanic eruptions and earthquakes follow each other. Parts of Iceland are frequently shaken by earth tremors. Catastrophic earthquakes occur at longer intervals than the volcanic eruptions. Some of the worst earthquakes devastated large areas of southern Iceland in 1784 and 1896. There are over a hundred volcanos on the central plateau which have not erupted in the past thousand years and between 30 and 40 that areactive, meaning that they have erupted within last few centuries.
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. The most famous and active volcano in Iceland is mount Hekla, which has erupted 18 times since 1104, the last time in 2000. Other active volcanos, measured in terms of the number of eruptions besides Hekla, are Grímsvötn, Katla, Askja and Krafla. Katla, has erupted about 20 times since the settlement of Iceland.
In 2010 Eyjafjallajökull volcano erupted and in 2011 Grímsvötn. The latest volcanic eruption was in Holuhraun from August 2014 to February 2015. The eruption produced a lava field of more than 85 km2 (33 sq mi) and 1.4 km3 (0.34 cu mi) – the largest in Iceland since 1783.
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