![]() Seismic studies provide limited images of the magmatic system. He was hit by a small bomb above his knee, but survived without injury only the woolen pants were burnt.Erebus volcano, Antarctica, with its persistent phonolite lava lake, is a classic example of an evolved, CO 2-rich rift volcano. Giggenbach had almost reached the inner crater floor, when an explosion occurred. On 23 December 1978, New Zealand volcanologist W. Scientists tried to descend into the inner crater in order to collect fresh samples. In 1978, the lava lake activity consisted of 1) lava upwelling in nearly circular areas, 2) small bubble-like degassing eruptions, and 3) downwelling of the consolidated crust along planar troughs or 'subduction zones.' Doming of the lava lake surface was occasionally observed, including one large bubble, that grew to ~80 m height before bursting. In 1978, the lake was 130 m wide and oval-shaped, with 2 zones of active upwelling of lava. Occasionally, such bombs were landing outside the crater. Strombolian eruptions were occurring from time to time, 2-10 per day typically, sometimes throwing bombs up to a few hundred meters above the outer rim. Throughout the 1970's, activity remained relatively constant, with a slight tendency of gradual increase in level. In 1976, it was noted that the lava lake had slowly increased since its discovery 4 years ago in 1972 and was about 100 m wide. (1997) "Volcanic gas emissions from Mount Erebus and their impact on the Antarctic environment", Journal of Geophysical Research, v. Zreda-Gostynska, G., Kyle, P., Finnegan, D., Prestbo, K.M. (2004) "40Ar/39Ar dating of the eruptive history of Mount Erebus, Antarctica: volcano evolution", Bulletin of Volcanology, v 66, pp 671-686. There is even a webcam on the rim of the crater! Satellites monitor CO2, SO2 and other gasses emitted by Erebus, which influence the Antarctic atmosphere, which is of particular importance to global climate. Erebus Volcano Observatory (MEVO), run by New Mexico Institute of Mining and Technology and the National Science Foundation, operates regular field surveys and measurements from McMurdo Station. ![]() There are only a handful long-lived lava lakes in the world: at Erta Ale volcano (Ethiopia), Nyiragongo (DRCongo), Ambrym (Vanuatu), often on Kilauea volcano on Hawai'i, and only occasionally on other volcanoes.Īlthough Erebus is perhaps in among the most inhospitable and remote location of any active volcano in the world, it is relatively well monitored. Heat supply is provided by rising magmatic gasses from the magma chamber through a liquid-filled conduit, and is counterbalanced by intense heat lost at the surface of the lava lake. Persistant lava lakes are very rare, and require a delicate equilibrium between heat supply and heat loss. The current activity at the lava lake includes spattering and sometime strombolian explosions, that can eject bombs outside the crater. Mt Erebus volcano's lava lake is connected to a long-lived, open and stable magma plumbing system, which might have been in place for the past 17,000 years. Mount Erebus is noted for its active anorthoclase-feldspar phonolite lava lake, which has been in continuous activity since at least 1972, but probably much longer. The summit consists of the elliptical 500 x 600 m wide, 110-m-deep crater, which contains the famous active lava lake, contained within a 250-m-wide, 100-m-deep inner crater. It contains a summit plateau at about 3200-m, marking the rim of the youngest caldera, which formed during the late-Pleistocene and within which the modern cone was constructed. The Erebus stratovolcano has undergone at least one or two caldera formations. The magma source beneath Erebus is sometimes described as a plume rising from the upper mantle at velocities of around 6 cm per year. This area is a rift zone where extension takes place and has thinned the crust to 20 km and allows magma to rise. Erebus volcano is an intraplate volcano and belongs to the McMurdo Volcanic Group, located in the so-called Terror Rift, which is part of the West Antarctic Rift System. View recent quakes Background Geologic setting
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