Wrapping close to the whole globe, Earth’s most comprehensive mountain variety stretches for more than 40,000 miles.
Practically solely submerged beneath the sea, it truly is recognised as the Mid-Ocean Ridge. It is, in essence, a big seam bordered by mountains where tectonic plates are pulling aside. New oceanic crust forms below as a result of volcanic exercise.
Iceland is one particular of the number of areas where the ridge rises over the floor, making it attainable to see the breathtaking impression of geologic processes that largely come about at the base of the sea.
Positioned alongside the Mid-Atlantic Ridge portion of the globe-girdling mountain variety, Iceland sits on the boundary among the Eurasian and North American tectonic plates. Right here, the plates are pulling aside in an east-west route at a amount akin to how rapid your fingernails increase. Molten rock wells up and fills in the gap, resulting in the development of new crust — and also ensuing in one particular of the most volcanically active regions on Earth.
As my colleague at Uncover, Erik Klemetti, writes in a new write-up at his Rocky Earth blog site, a new eruption may be in the offing in Southern Iceland, though which is a little bit unsure right now.
I was blessed ample to pay a visit to Iceland previous summer months. While there, I took the picture over of Hverfjall, a tephra cone volcano in the north that erupted about 2,500 a long time back. The crater has steep, round walls in portion due to the fact the volcano erupted in the vicinity of a shallow lake.
The Landsat 8 satellite captured this picture of Iceland’s Northern Volcanic Zone on July 26, 2017. Hverfjall is visible to the right of Mývatn, a attractive shallow lake that hosts a wonderful range of lifetime. (Source: NASA Earth Observatory)
You can see that lake, as nicely as Hverfjall, in the view over from room, just lately posted by NASA’s Earth Observatory. For a substantial-resolution variation displaying a broader view of this northern portion of Iceland, click on below. Simply click once again to discover shut-up views.
Mývatn, the lake in query, gets it title from wide numbers of midges that breed there. The Mývatn region also hosts “one particular of the world’s richest populations of breeding aquatic birds,” in accordance UNESCO. “In all, one hundred fifteen species of birds have been recorded in the region, which includes 28 species of ducks.”
A mountaineering path as a result of volcanic formations on west facet of the Mývatn. (Source: © Tom Yulsman)
The wonderful waters of Mývatn are visible in the length in this picture shot from a mountaineering path that wends its way as a result of volcanic formations on east facet of the lake.
Mývatn and Hverfjall are situated in Icelabnd’s Northern Volcanic Zone. Right here, the entire amount of spreading among the North American and Eurasian plates is taking place, 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 — “ample to pave the whole U.S. interstate freeway process to a depth of ten meters,” in accordance to NOAA.
An approximated eighty million tons of sulfuric acid aerosol was released by the eruption — eighty 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 ten,000 Icelanders, a quarter of the populace at that time.
By blocking sunlight, the haze brought on wintertime common temperature in the japanese United States to plunge nearly five degrees C beneath the prolonged-term common. For the Northern Hemisphere as a entire, the fall amounted to about 1 degree C. To place that in standpoint, human things to do have brought on Earth’s common temperature to rise by about the exact same total.
Some thing like that could surely occur once again. But most of the time, eruptions are more benign.