Abstract
Landsat Thematic Mapper (TM) images acquired in 1984 and 1985 revealed a pronounced thermal anomaly on Lascar volcano, north Chile. Subsequent images showed that the anomaly was persistent but variable and that after a significant eruption on 16 September 1986 it was weaker and divided into several sources. TM studies and other observations of Lascar indicate that the persistent thermal anomaly may be due to high-temperature fumaroles within the summit crater. GOES weather satellite images and field investigations confirm that the 16 September event was a short-lived, Vulcanian-type eruption, which produced an ash column that reached 15 km altitude. The ash cloud can be tracked on GEOS images to about 400 km downwind and covered an area > 112 000 km2. Transport occurred in the upper troposphere at speeds up to 180 km/h. Ash fall from the plume was well sorted and moderately fine grained (Md 200 µm). Formation and fallout of ash as aggregates was unimportant in the deposition of the ash layer. Although small, the Lascar 16 September eruption is significant because few historic eruptions have been recorded in the central Andes. Little would have been known of the eruption in the absence of remote-sensed data.
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Brazier S, Davis AN, Sigurdsson H, Sparks RSJ (1982) Fall-out and deposition of volcanic ash during the 1979 explosive eruption of the Soufriere of St Vincent. J Volcanol Geotherm Res 14:319–334
Brazier S, Sparks RSJ, Carey SN, Sigurdsson H, Westgate JA (1983) Bimodal grain size distribution and secondary thickening in air-fall ash layers. Nature 301:115–119
Carey SN, Sigurdsson H (1982) Influence of particle aggregation on deposition of distal tephra from the May 18, 1980, eruption of Mount St. Helens volcano. J Geophys Res 87:7061–7072
Casertano I (1963) Catalogue of the active volcanoes of the world, including solfatara fields. Part XV. The Chilean continent. International Association of Volcanology and Chemistry of the Earth's Interior 55, Naples
Casertano L, Barozzi R (1961) Informe sobre el sistema volcanic del Lascar. Santiago. Universidad de Chile Faculdad de Ciencias Fiscias y Matematicas, Instituto de Geologia, Publ No 23:304–315
Deruelle B (1985) Le Volcan Lascar: geologie et petrologie. IV Congreso Geologico Chileno, Agosto 1985 4:120–137.
Dozier J (1981) A method for satellite identification of surface temperature fields of sub-pixel resolution. Remote Sensing Environ 11:221–229
Francis PW, Rothery DA (1987) Using the Landsat Thematic mapper to detect and monitor volcanic activity: an example from Lascar volcano, north Chile. Geology 15:614–617
Glaze LS, Francis PW, Rothery DA (1989) Using Landsat Thematic Mapper to monitor radiant thermal energy budgets of active volcanoes. Nature 338:144–146
Harris DM, Rose WI, Roe R, Thompson MR (1981) Radar observations of ash eruptions. US Geol Surv Prof Pap 1250:323–333
Kasten F (1968) Falling speed of aerosol particles. J Appl Meteorol 7:944–947
Kienle J, Shaw GE (1979) Plume dynamics, thermal energy and long-distance transport of vulcanian eruption clouds from Augustine volcano, Alaska. J Volcanol Geotherm Res 6:139–164
Malingreau J-P, Kaswanda (1986) Monitoring volcanic eruptions in Indonesia using weather satellite data: The Colo eruption of July 28, 1983. J Volcanol Geotherm Res 27:179–194
Matson M, Dozier J (1981) Identification of subresolution high temperature sources using a thermal IR sensor. Photogramm Eng Remote Sensing 47:1311–1318
Moore JG, Rice CJ (1984) Chronology and Character of the May 18, 1980, explosive eruptions of Mount St. Helens. Explosive Volcanism: inception, evolution and hazards. National Academy Press, Washington, DC, pp 133–142
Nautical Almanac for the year 1986 (1984) US Government Printing Office, Washington, DC, p 183
Robock A, Matson M (1983) Circumglobal transport of the El Chichon volcanic dust cloud. Science 21:195–197
Rothery DA, Francis PW, Wood CA (1988) Volcano monitoring using short wavelength infra-red data from satellites. J Geophys Res 93:7993–8008
Sarna-Wojcicki AM, Shipley S, Waitt RB, Dzurisin D, Wood SH (1981) Areal distribution, thickness, mass, volume and grain size of air-fall ash from the six major eruptions of 1980. US Geol Surv Prof Pap 1250:577–600
Sawada Y (1983) Analysis of eruption clouds by the 1981 eruptions of Alaid and Pagan volcanoes with GMS images. Pap Meteorol Geophys 34:307–324
SEAN Bulletin (1986) Smithsonian Institution, Washington, DC 11:8:13
SEAN Bulletin (1987a) Smithsonian Institution, Washington, DC 12:4:3
SEAN Bulletin (1987b) Smithsonian Institution, Washington, DC 12:5:4
SEAN Bulletin (1988) Smithsonian Institution, Washington, DC 13:8:9
Sparks RSJ, Moore JG, Rice CJ (1986) The initial giant umbrella cloud of the May 18th, 1980, explosive eruption of Mount St Helens. J Volcanol Geotherm Res 28:257–274
Walker GPL, Wilson L, Bowell EIG (1971) Explosive volcanic eruptions -I. The rate of fall of pyroclastics. Geophys J R Astron Soc 22:377–383
Wilson L, Huang TC (1979) The influence of shape on the atmospheric settling velocity of volcanic ash particles. Earth Planet Sci Lett 44:311–324
Zen MT, Hadikusumo D (1965) Preliminary report on the 1963 eruption of Mt. Agung in Bali (Indonesia). Bull Volcanol 27:269–299
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Glaze, L.S., Francis, P.W., Self, S. et al. The 16 September 1986 eruption of Lascar volcano, north Chile: Satellite investigations. Bull Volcanol 51, 149–160 (1989). https://doi.org/10.1007/BF01067952
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DOI: https://doi.org/10.1007/BF01067952