The one in the NE sector of the inner crater has been persistent almost continuously since first reported in 1972. The two primary lava lakes remained active at Erebus. The largest peaks in terms of numbers of eruptions were during 1995, 1997, 1998, 2000, and a broad peak beginning in late 2005 that continued into late 2006 (BGVN 31:12).Īctivity during 2010-2016. Vent and lava lake eruptions were recorded by MEVO during the late 1990s and early 2000s. These were the first known phreatic eruptions at Erebus, and probably resulted from steam build-up associated with melting snow in the crater (BGVN 20:11). On 19 October 1993, two moderate phreatic eruptions created a new crater ~80 m in diameter on the main crater floor and ejected debris over the northern crater rim. Small ash eruptions were observed from an active vent near the lava lakes in January 1991. Two primary lakes of phonolitic lava, and a third transient lake, were present inside the crater during the late 1980s (see figure 9, SEAN 13:02), and infrequent Strombolian eruptions with small bombs were captured by a remote video camera mounted on the crater rim. A small lava lake about 15 m in diameter reappeared late in 1985. The eruptions were witnessed from 60 km away and explosions could be heard up to 2 km from the volcano (SEAN 11:03). During this period of increased activity, bombs averaging 2 m in diameter (but some as large as 10 m in diameter) were ejected up to 1.2 km from within the inner crater. Seismicity remained above average through January 1985. Observations in October 1984 indicated that much of the lava lake had solidified, and that the surface was covered with ejecta from the recent explosions. Ash also covered the NW flank down to 3,400 m elevation. During September 1984, numerous large explosions sent ejecta as high as 600 m above the summit, and incandescence was visible from 70 km away. Oscillations of the lake level of up to 2 m were observed.ĭuring a period of increased activity between September 1984 and January 1985, several large explosions were recorded by the seismic network, and there were reports of mushroom-shaped clouds rising as much as 2 km above the summit. Bombs up to 10 m in in diameter were ejected near the vent, and ones up to 30 cm in diameter were thrown out over the main crater. During the 1970's, the lava lake was observed to be about 130 m long and oval shaped, producing occasional Strombolian explosions. Courtesy of the University of Cambridge Department of Geography. Several other devices are seen in the background, all trained on the lava lake on the floor of the crater. There are two dishes, to both transmit and receive data. Radar altimeter installed at the crater rim of Erebus in December 2016. One area of ongoing volcanology research relates to studying the behavior of the lava lake with a variety of on-site monitoring equipment (figure 17).įigure 17. A final report was submitted to the National Science Foundation (NSF) on the past research and ideas for future research (Mattioli and LaFemina, 2016), and includes a comprehensive list of scientific publications about Erebus. The Mount Erebus Volcano Observatory closed in 2016. Researchers from New Mexico Tech, the University of Cambridge, and University College London made yearly expeditions there between 20. During the early 2000s MEVO also used infrasonic recordings to capture data on the frequency of eruptions. Between 19 as many as 10 seismic stations were recording activity at Erebus they were monitored by the Mount Erebus Volcano Observatory (MEVO) run by the New Mexico Institute of Mining and Technology (New Mexico Tech). Seismometers were initially installed by a joint project of United States, New Zealand, and Japanese scientists in 1980-1981. For most years since the 1970's, scientists have visited Erebus during the austral summer (November-February) and gathered samples, taken SO 2 and other geochemical measurements, collected GPS data, and made observations and overflights to evaluate the condition of the volcano. Observations from MODVOLC data collected from 2000 through 2016 are also discussed. Photographs from expeditions between 20 show more recent activity at the volcano. This report briefly summarizes research activity at Mount Erebus, and volcanic activity observed since 1972. McMurdo Station is about 40 km S of the summit of Mount Erebus. On 31 December 2013, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite acquired visible near-infrared images of the western end of Ross Island in austral mid-summer.
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