9/3/2023 0 Comments Mount erebus volcano![]() We suggest that, in both cases, the magma was well mixed at the time melt inclusions were incorporated into the different mineral phases. In-situ analyses of Pb isotopes in melt inclusions hosted in an anorthoclase crystal from a 1984 Erebus phonolite bomb and in an olivine from a DVDP basanite are uniform and identical to the host lavas within analytical uncertainties. Magma mixing is inferred to play a fundamental role in establishing the isotopic and compositional uniformity in the evolved phase-three phonolites. It is notable for its persistent convecting. The Erebus time series data show a marked distinction between the early-phase basanites and phonotephrites, whose Nd, Hf, Sr, and Pb isotope compositions are variable (particularly Pb), and the current ‘phase-three’ evolved phonolitic lavas and bombs, whose Nd, Hf, Sr, and Pb isotope compositions are essentially invariant. Mount Erebus is an alkaline stratovolcano just off the shore of the Antarctic main land (77 33S, 167 10E). The Erebus volcano samples have radiogenic 206Pb/204Pb, unradiogenic 87Sr/86Sr, and intermediate 143Nd/144Nd and 176Hf/177Hf, and lie along a mixing trajectory between the two end-member mantle components DMM and HIMU. Morning and the Dry Valley Drilling Project (DVDP) are given for comparison. The samples cover the entire compositional range from basanite to phonolite and trachyte, and represent all three phases of the volcanic evolution from 1.3 Ma to the present. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: ) Sentinel Hub Playground (URL: ).We report new Nd, Hf, Sr, and high-precision Pb isotopic data for 44 lava and tephra samples from Erebus volcano. Information Contacts: Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. Continuous lava-lake activity with minor explosions, punctuated by occasional larger Strombolian explosions that eject bombs onto the crater rim, has been documented since 1972, but has probably been occurring for much of the volcano's recent history. ![]() The glacier-covered volcano was erupting when first sighted by Captain James Ross in 1841. An elliptical 500 x 600 m wide, 110-m-deep crater truncates the summit and contains an active lava lake within a 250-m-wide, 100-m-deep inner crater other lava lakes are sometimes present. ![]() A summit plateau at about 3,200 m elevation marks the rim of the youngest caldera, which formed during the late-Pleistocene and within which the modern cone was constructed. ![]() The summit of the dominantly phonolitic volcano has been modified by one or two generations of caldera formation. It is the largest of three major volcanoes forming the crudely triangular Ross Island. Mount Erebus, the world's southernmost historically active volcano, overlooks the McMurdo research station on Ross Island. The table was compiled using data provided by the HIGP - MODVOLC Thermal Alerts System. See BGVN 42:06 for data from 2000 through 2016. Number of monthly MODIS-MODVOLC thermal alert pixels recorded at Erebus during 2017-2021. Images use False Color rendering (bands 12, 11, 4). An older cone of Mount Erebus (Fang Volcano), composed largely of benmoreite, was partly destroyed by an unknown event, leaving a caldera of about 6-kilometers diameter. The image on 23 January 2021 (left) shows a single lava lake, while the image on 30 October 2021 (right) shows a larger lake at least one smaller thermal area immediately SW. Sentinel-2 infrared satellite images showing the active lava lake in the summit crater of Erebus during 2021. Based on MODIS infrared detectors aboard the Terra and Aqua satellites and analyzed using the MODVOLC algorithm, thermal activity during 2021 was much greater than the 2020 level (76) but much less than the 20 levels (774 and 624, respectively) (table 7).įigure 30. ![]() Occasionally, a white gas plume was visible. Sentinel-2 satellite images during 2021 showed a single lava lake, except a much smaller second one on 30 October (figure 30). This report documents activity during 2021. Erebus Volcano Observatory suspended their seismic and infrasonic monitoring program in 2016, the volcano has been primarily monitored by satellite. Since 1972, and probably well before, minor explosions, punctuated by occasional larger Strombolian explosions, have been associated with the active lava lake. 3794 m All times are local (unless otherwise noted)Įrebus, located on Ross Island, Antarctica, is one of the few volcanoes in the world with a persistent lava lake in its summit crater. Erebus Antarctica 77.53°S, 167.17☎ summit elev. ![]()
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