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#Mount erebus mac os
#Mount erebus pdf

This evidence of aerosol dispersal across the continent is likely from the passive degassing of the volcano rather than an explosive event. Most known eruptions at Erebus dating back several thousand years are only up to a VEI 2, so there is no evidence that Erebus has large explosive eruptions, although tephra/ash/aerosols from the volcano is found in the ice across Antarctica.

Notable Recent Eruptions and History: The volcano was erupting in 1841 when it was discovered by James Ross and has erupted frequently since then, upwards of 200 times between 1986-1990 alone.

There has been frequent harmonic tremor noted at Erebus since 2000 and likely represents the emplacement of a dike at depth, although the main reservoir for the volcano is believe to lie only tens to hundreds of meters below the crater floor (Aster et al., 2003). There is a collection of movies of Erebus erupting available on the MEVO website and are well worth the time. The volcano has frequent strombolian eruptions that have been detected remotely via – video and infrasound monitoring. The phonolite lava lake in the inner crater at Mt. Since 250,000 years ago, Erebus has erupted at an average rate of 1.2 to 4.0 km 3/1000 years, which is relatively low for volcanoes of its type. Most of the summit features at Erebus are likely less than 37,000 years old, although ancestral volcanoes dating as far back as 1.3 million years existed in the spot that Erebus sits (Esser et al., 2004). The lava lake was buried briefly in 1987 by a landslide (similar to what happened at Halema'uma'u Crater this year), but lava retook the bottom of the crater to form a new lake by 1990. Most crystals in erupting lava are less than a centimeter in size, so these aptly-called megacrysts are quite unique (and not well understood).

#Mount erebus pdf

One of the most remarkable features in the lava lake are the up-to-10-cm anorthoclase crystals ( pdf link) in the lava. This crater is 120 meters / 400 feet deep with a inner crater that is 100 m / 3~300 feet deep where the convecting phonolite lava lake sits. The lava lake has a variable 5 to 15 meter / 15 to 45 foot radius inside the main crater on the volcano.

Erebus is one of the few volcanoes in the world (along with Erta'Ale, Nyiragongo, Kilauea, Villarrica and Masaya) with an active lava lake and this lake has been present since at least the 1960's. These compositions are typical in rift systems and are found at places like the East African Rift or the Rhine Graben in Germany. Erebus erupts silica-undersaturated lavas in the form basanite and phonolite ( note: most lavas, like basalt or rhyolite, are silica-saturated). Erebus imaged by the NASA EO-1 satellite. There is also a live webcam to watch the volcano as well.

#Mount erebus mac os

If you want to do some monitoring at home, there is even an Mac OS Dashboard app for MEVO with current information of the volcano. Erebus also lies close to McMurdo Station. Erebus even once has a robotic explorer attempt to descend into the crater, but it ran into some trouble. The volcano is also closely watched via satellite (see below), examining the temperature of the surface of the lava lake and the SO 2 flux. There website has one of the most remarkable archives of information on a single volcano on the internet. Erebus Volcano Observatory (MEVO), run by New Mexico Institute of Mining and Technology and the National Science Foundation.

Hazards: Lava flows, some minor explosions from Strombolian-style eruptions, tephra/ash fall.

This is what is driving the extension in the Terror Rift graben.

The source of the magma at Erebus is referred to as the " Erebus Plume" that is rising from asthenosphere (in the mantle) at velocities of ~6 cm/year. This is an intracontinental rift zone that drives extension, producing the Terror Rift graben, which also hosts other nearby volcanoes on Ross Island (Mt. Geophysical location: Erebus lies in the West Antarctic Rift System over relatively thin (20 km) crust in what is (excellently) called the Terror Rift.Location: Antarctica* (technically, it is on the part of Antarctica claimed by New Zealand, but the Antarctic Treaty System more or less makes the continent an international zone.).