Wrapping all around the overall globe, Earth’s most comprehensive mountain variety stretches for more than 40,000 miles.
Practically solely submerged beneath the sea, it really is known as the Mid-Ocean Ridge. It is, in essence, a large seam bordered by mountains where by tectonic plates are pulling apart. New oceanic crust types below as a result of volcanic exercise.
Iceland is just one of the couple of locations where by the ridge rises higher than the surface area, creating it feasible to see the breathtaking effects of geologic processes that generally occur at the bottom of the sea.
Positioned along the Mid-Atlantic Ridge part of the globe-girdling mountain variety, Iceland sits on the boundary between the Eurasian and North American tectonic plates. Listed here, the plates are pulling apart in an east-west course at a charge akin to how quickly your fingernails increase. Molten rock wells up and fills in the gap, resulting in the creation of new crust — and also ensuing in just one of the most volcanically active locations on Earth.
As my colleague at Find out, Erik Klemetti, writes in a the latest submit at his Rocky Earth blog site, a new eruption may be in the offing in Southern Iceland, although that’s a bit unsure right now.
I was blessed adequate to pay a visit to Iceland past summer months. When there, I took the picture higher than of Hverfjall, a tephra cone volcano in the north that erupted about two,500 a long time back. The crater has steep, round walls in portion because the volcano erupted near a shallow lake.
The Landsat eight satellite captured this graphic of Iceland’s Northern Volcanic Zone on July 26, 2017. Hverfjall is seen to the right of Mývatn, a stunning shallow lake that hosts a terrific range of lifestyle. (Source: NASA Earth Observatory)
You can see that lake, as well as Hverfjall, in the see higher than from place, not long ago released by NASA’s Earth Observatory. For a higher-resolution version showing a broader see of this northern part of Iceland, click on below. Click on again to examine close-up sights.
Mývatn, the lake in issue, receives it title from extensive quantities of midges that breed there. The Mývatn place also hosts “just one of the world’s richest populations of breeding aquatic birds,” in accordance UNESCO. “In all, 115 species of birds have been recorded in the place, including 28 species of ducks.”
A hiking path as a result of volcanic formations on west facet of the Mývatn. (Source: © Tom Yulsman)
The pretty waters of Mývatn are seen in the distance in this picture shot from a hiking path that wends its way as a result of volcanic formations on east facet of the lake.
Mývatn and Hverfjall are positioned in Icelabnd’s Northern Volcanic Zone. Listed here, the full charge of spreading between the North American and Eurasian plates is happening, ensuing in recurring episodes of rifting and volcanic eruptions.
In the southern portion of Iceland, the Laki eruption of 1783 poured out more than 12 cubic kilometers of lava — “adequate to pave the overall U.S. interstate freeway system to a depth of 10 meters,” in accordance to NOAA.
An estimated 80 million tons of sulfuric acid aerosol was introduced by the eruption — 80 moments more than Mount St. Helens. Haze from the eruption ruined crops and killed most of the island’s livestock, resulting in the death of more than 10,000 Icelanders, a quarter of the population at that time.
By blocking daylight, the haze induced wintertime ordinary temperature in the jap United States to plunge nearly 5 degrees C underneath the long-term ordinary. For the Northern Hemisphere as a whole, the drop amounted to about one diploma C. To put that in viewpoint, human functions have induced Earth’s ordinary temperature to increase by about the identical volume.
Anything like that could certainly transpire again. But most of the time, eruptions are more benign.