![]() ![]() Subsequently, it turned out that Erebus was capable not only of causing delight, but also of inspiring terror. “A terrific volcano in an extremely active state,” was how the ship’s doctor on James Ross’s expedition described it. And do not scare a colony of half a million Adelie penguins living on the ice of Ross Island.Ĭareful study of the unique volcano is facilitated by its relative proximity to the main Antarctic research stations of the USA (McMurdo) and New Zealand (Scott Base), which are about 35 km away from it. These bright natural cataclysms look very picturesque against the background of the ice shell of Antarctica. Reaching the stratosphere, they destroy the ozone layer, which is why its minimum thickness is observed above the Ross Sea, where volcano Erebus is located. Lava is ejected from the lake or from one of several holes within the inner crater of the volcano, but the lava remains inside the caldera and does not spurt out of it.Įrebus is located at the intersection of crustal faults, from which, according to volcanologists, there are periodic massive outbursts of deep gases, including hydrogen and methane. At eruption moments the gushing geysers also show themselves. The last one was observed in 2011.ĭuring eruptions, clouds of steam are observed, accompanied by rare emissions of ash and volcanic bombs up to 10 meters in diameter, which fall around Erebus within a radius of one and a half kilometers. This means that the sluggish eruption lasts continuously, the volcano maintains a constant readiness for a stronger, but shorter eruption. Below it takes the form of a vertical channel descending to a depth of up to 400 km.Įrebus is referred to the “Strombolian” type of eruption, named after a volcano in the Tyrrhenian Sea. It is a lake of magma up to 300 km in diameter at a depth of about 200 km. The underground source of magma that feeds it into the crater of Erebus volcano was common to all other volcanoes on the island, now extinct. Erebus is the only active volcano on Earth, spewing kenite magma at a temperature of +900☌, this rock in a solid state is also found in the mountains of Kenya (hence the name). Erebus is one of several volcanoes on Earth whose lake of molten kenite (a type of phonolite) has existed for quite a long time – several decades. At its bottom is a smaller crater about a kilometer deep, and in it is a lake of molten lava. The crater of the volcano is a caldera about a kilometer in diameter, which are constantly acting fumaroles and geysers. Explorers tell us that it is pitch-black in the depths, and when they turn on flashlights, the black walls turn into a multicolored kaleidoscope of flying sparks. Its bottom is wet, soft soil and rocks, and its walls are ice. The most famous of these ice cavities has earned its own name – Warren Cave, created by vapors from the volcano. Waves also break through the caves in the glacier, where the temperature stays around 0☌, and humidity is 100%, which contributes to the formation of huge icicles, similar to stalactites, and large ice crystals. In summer, the ice melts and the broken off parts of the glacier form icebergs. ![]() Approaching the shore, it sinks into the water and stays on its surface: in this place it is quite deep. The largest tongue is 50 to 300 meters thick. From above they are covered by glaciers that descend to the ocean. The base of the volcano is made up of volcanic rocks: basalt, trachyte, phonolite and tuff. ![]() Magma beneath Erebus rises from the upper mantle at a rate of about 6 cm/year. The island is generally lucky with volcanoes: in addition to Erebus there is extinct shield Terror (3230 m) about a million years old and a couple of lower volcanoes – Terra Nova (2130 m) and Bird (1765 m).Įrebus volcano is an intraplate volcano and belongs to the McMurdo volcanic group, part of the West Antarctic Rift System. Higher is only an extinct Sidley (4285 m) on Mary Baird Land.Įrebus is not located on the continental part of Antarctica, but on the large (2460 km2) Ross Island, and it is not the only volcano on it. Antarctica’s southernmost and most active volcanoĮrebus is the second highest and most active volcano in Antarctica. Captain James Ross was sure he had found Antarctica, but it was still only a volcanic island. As the sailing ships Erebus and Terror approached the solid strip of ice, the members of the expedition saw a tall white cone far to the south, over which clouds of smoke were rising. ![]()
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