Most volcanoes at sea are like Hawaii and the Azores, which we describe as hot spots. The ones that scientists have observed happen on land. A classic example is the Cascade range in the north-western US, whose most famous volcano is Mt St Helens. Many volcanoes are caused by subduction, which is where two of the Earth’s tectonic plates crash against one another, sending one plate down and pushing the other upwards. Yet from a volcanic point of view, Deception is a great puzzle. Nowadays there are hazard maps to make visitors aware of the higher-risk spots on the island. We understand these subglacial eruptions much better now than we did in the 1960s. Ironically, the absence of larger glaciers is what made the island the most hospitable location in Antarctica. The scientists were not expecting it to produce much more than steam. The reason why this melting was unexpected was because in scientific terms the glacier was “deceptively thin”. This was the main cause of the destruction of the UK and Chilean stations. This meant that it turned the glacier into meltwater as well as steam, creating a large overflow of mud to the surface. Scientists would normally expect that if this were hit by lava from below, it would evaporate benignly into steam.īut the lava moving upwards at Deception has several qualities that made things happen differently: it moves slowly and it has high water content. The island is situated in a place where there is a glacier on the ocean floor about 100m thick. A thermal anomaly has been observed underneath Ross Island and this is thought to represent a mantle plume feature which is responsible for the volcanism of Ross Island (Gupta, Zhao & Rai 2009).The volcanic events at Deception fall into a rare category called subglacial eruptions. This is in turn associated with the West Antarctic Rift System making Mount Erebus one of many volcanoes associated with this larger continental scale rift system (Kyle 1990). The volcano is directly associated with the Terror Rift (Behrendt 1999). The mountain produces frequent strombolian style eruptions from a convecting phonolitic lava lake which is located at the bottom of the main Crater (Panter & Winter 2008). At least one plinian eruption has occurred from Mt Erebus within this time frame (Harpelet al. Within the last 95,000 years eruptive activity in the summit region of Mount Erebus has included lava flows, Small strombolian eruptions and at least one, possibly two caldera forming events. Mount Erebus is classed as an alkaline intraplate stratovolcano (Behrendt 1999) and has been produced by distinct volcanic phases (Esser, Kyle & McIntosh 2004). It dominates the landscape of Ross Island and its volcanic structure and the processes which have led to the formation of these features are discussed in this review with close reference to Esser, Kyle and McIntosh (2004). Mount Erebus is the Worlds southernmost active volcano and is 3794 meters high. Since then it has been studied extensively, and numerous papers have been Written on its geology. In 1972 yearly observations of the volcanoe's lava lake were begun (From Kyle 1982 as cited in Harpel et al. ROSS Island is the base for both New Zealand's Scott Base and the USAS McMurdo Station and this has resulted in the volcanoes frequent observation since 1956. ![]() It is located on Ross Island in the Ross Sea of Antarctica (Harpel et al. ![]() Mount Erebus was discovered in 1841 and for the moment it is the most active Volcano on the Antarctic continent. This review aims to outline current geological knowledge surrounding the Mount Erebus Volcano and its association with the wider tectonic setting present in Antarctica.
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