![]() ![]() This makes it of special interest for studying oligotrophs – organisms that can survive on minimal amounts of resources. The life is sparse, mainly bacteria and fungi. The ice caves associated with the fumaroles are dark, in polar alpine environments starved in organics and with oxygenated hydrothermal circulation in highly reducing host rock. Erebus is notable for its numerous ice fumaroles – ice towers that form around gases that escape from vents in the surface. These results demonstrated a complex upper-volcano conduit system with appreciable upper-volcano magma storage to the northwest of the lava lake at depths hundreds of meters below the surface. By studying the refracted and scattered seismic waves, the scientists produced an image of the uppermost (top few km) of the volcano to understand the geometry of its "plumbing" and how the magma rises to the lava lake. Researchers spent more than three months during the 2007–08 field season installing an atypically dense array of seismometers around Mount Erebus to listen to waves of energy generated by small, controlled blasts from explosives they buried along its flanks and perimeter, and to record scattered seismic signals generated by lava lake eruptions and local ice quakes. It is estimated that around 80 grams of gold are released by the volcano in this manner each day. The active lava lake in this summit cone undergoes continuous degassing.įollowing studies conducted in the early 1990s, it was found that Mount Erebus releases small amounts of gold crystals in the gases produced from the volcano these crystals range in size from 20 to 60 micrometres. In the center of the summit caldera is a small, steep-sided cone composed primarily of decomposed lava bombs and a large deposit of anorthoclase crystals known as Erebus crystals. It is filled with small volume tephritic phonolite and phonolite lava flows. The summit caldera was created by an explosive VEI-6 eruption that occurred 18,000 ± 7,000 years ago. A conspicuous break in slope around 3,200 m ASL calls attention to a summit plateau representing a caldera. The upper slopes of Mount Erebus are dominated by steeply dipping (about 30°) tephritic phonolite lava flows with large-scale flow levees. Lava flows of more viscous phonotephrite and trachyte erupted after the basanite. Erebus is the world's only presently erupting phonolite volcano. Slightly younger basanite and phonotephrite lavas crop out on Fang Ridge – an eroded remnant of an early Erebus volcano – and at other isolated locations on the flanks of Erebus. The oldest eruptive products consist of relatively undifferentiated and nonviscous basanite lavas that form the low broad platform shield of Erebus. The composition of the current eruptive products of Erebus are anorthoclase- porphyritic tephritic phonolite and phonolite, which are the bulk of exposed lava flow on the volcano. The bottom half of the volcano is a shield and the top half is a stratocone. Mount Erebus is classified as a polygenetic stratovolcano. Scientific study of the volcano is also facilitated by its proximity to McMurdo Station (U.S.) and Scott Base (New Zealand), both sited on the same island around 35 km away. The volcano is scientifically remarkable in that its relatively low-level and unusually persistent eruptive activity enables long-term volcanological study of a Strombolian eruptive system very close (hundreds of metres) to the active vents, a characteristic shared with only a few volcanoes on Earth, such as Stromboli in Italy. Characteristic eruptive activity consists of Strombolian eruptions from the lava lake or from one of several subsidiary vents, all within the volcano's inner crater. The summit contains a persistent convecting phonolitic lava lake, one of five long-lasting lava lakes on Earth. It is the current eruptive centre of the Erebus hotspot. Mount Erebus is the world's southernmost active volcano. Geology and volcanology Anorthoclase crystal (45 mm long) from Mt. The volcano was the site of the Air New Zealand Flight 901 accident, the Mount Erebus disaster, which occurred in November 1979. The volcano has been active since about 1.3 million years ago and has a long-lived lava lake in its inner summit crater that has been present since at least the early 1970s. With a summit elevation of 3,794 metres (12,448 ft), it is located in the Ross Dependency on Ross Island, which is also home to three inactive volcanoes: Mount Terror, Mount Bird, and Mount Terra Nova. It is the sixth-highest ultra mountain on the continent. Mount Erebus ( / ˈ ɛr ɪ b ə s/) is the second-highest volcano in Antarctica (after Mount Sidley), the highest active volcano in Antarctica, and the southernmost active volcano on Earth. (claimed by New Zealand as part of the Ross Dependency) ![]()
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