Bulletin of Volcanology

, Volume 56, Issue 6–7, pp 435–446 | Cite as

Eruptive activity at Mount St Helens, Washington, USA, 1984–1988: a gas geochemistry perspective

  • K. A. McGee
  • A. Jefferson Sutton
Original Paper


The results from two different types of gas measurement, telemetered in situ monitoring of reducing gases on the dome and airborne measurements of sulfur dioxide emission rates in the plume by correlation spectrometry, suggest that the combination of these two methods is particularly effective in detecting periods of enhanced degassing that intermittently punctuate the normal background leakage of gaseous effluent from Mount St Helens to the atmosphere. Gas events were recorded before lava extrusion for each of the four dome-building episodes at Mount St Helens since mid-1984. For two of the episodes, precursory reducing gas peaks were detected, whereas during three of the episodes, COSPEC measurements recorded precursory degassing of sulfur dioxide. During one episode (October 1986), both reducing gas monitoring and SO2 emission rate measurements simultaneously detected a large gas release several hours before lava extrusion. Had both types of gas measurements been operational during each of the dome-building episodes, it is thought that both would have recorded precursory signals for all four episodes. Evidence from the data presented herein suggests that increased degassing at Mount St Helens becomes detectable when fresh upward-moving magma is between 2 km and a few hundred meters below the base of the dome and between about 60 and 12 hours before the surface extrusion of lava.

Key words

Mount St Helens gas COSPEC sulfur dioxide in situ monitoring reducing gas 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Bandy AR, Maroulis PJ, Wilner LA, Torres AL (1982) Estimates of fluxes of NO, SO2, H2S, CS2 and OCS from Mount St. Helens deduced from in situ plume concentration measurements. Geophys Res Lett 9:1097–1100Google Scholar
  2. Casadevall TJ, Greenland LP (1981) The chemistry of gases emanating from Mount St. Helens, May–September 1980. In: Lipman PW, Mullineaux DR (eds) The 1980 Eruptions of Mount St. Helens, Washington. US Geol Surv Prof Pap 1250:221–226Google Scholar
  3. Casadevall TJ, Johnston DA, Harris DM, Rose WI, Malinconico LL, Stoiber RE, Bornhorst TJ, Williams SN, Woodruff L, Thompson JM (1981) SO2 emission rates at Mount St. Helens from March 29 through December, 1980. In: Lipman PW, Mullineaux DR (eds) The 1980 Eruptions of Mount St. Helens, Washington. US Geol Surv Prof Pap 1250:193–200Google Scholar
  4. Casadevall TJ, Rose WI, Gerlach TM, Greenland LP, Ewert J, Wunderman S, Symonds R (1983) Gas emissions and the eruptions of Mount St. Helens through 1982. Science 221:1383–1385Google Scholar
  5. Casadevall TJ, Rose WI, Fuller WH, Hunt WH, Hart MA, Moyers JL, Woods DC, Chuan RL, Friend JP (1984) Sulfur dioxide and particles in quiescent volcanic plumes from Poás, Arenal, and Colima volcanoes, Costa Rica and Mexico. J Geophys Res 89:9633–9641Google Scholar
  6. Casadevall TJ, Stokes JB, Greenland LP, Malinconico LL, Casadevall JR, Furukawa BT (1987) SO2 and CO2 emission rates at Kilauea volcano, 1979–1984. In: Decker RW, Wright TL, Stauffer PH (eds) Volcanism in Hawaii. US Geol Surv Prof Pap 1350:771–780Google Scholar
  7. Chadwick WW, Archuleta RJ, Swanson DA (1988) The mechanics of ground deformation precursory to dome-building extrusions at Mount St. Helens 1981–1982. J Geophys Res 93:4351–4366Google Scholar
  8. Crafford TC (1975) SO2 emission of the 1974 eruption of Volcán Fuego, Guatemala. Bull Volcanol 39:536–556Google Scholar
  9. Dzurisin D (1992) Electronic tiltmeters for volcano monitoring: lessons from Mount St. Helens. In: Ewert JW, Swanson DA (eds) Monitoring Volcanoes: Techniques and Strategies Used by the Staff of the Cascades Volcano Observatory, 1980–90. US Geol Surv Bull 1966:69–83Google Scholar
  10. Endo ET, Murray TL (1991) Real-time seismic amplitude measurement (RSAM): a volcano monitoring and prediction tool. Bull Volcanol 53:533–545Google Scholar
  11. Endo ET, Dzurisin D, Swanson DA (1990) Geophysical and observational constraints for ascent rates of dacitic magma at Mount St. Helens. In: Ryan MP (ed) Magma Transport and Storage. Wiley, Chichester, pp 317–334Google Scholar
  12. Gerlach TM, Casadevall TJ (1986) Fumarole emissions at Mount St. Helens volcano, June 1980 to October 1981: degassing of a magma-hydrothermal system. J Volcanol Geotherm Res 28:141–160Google Scholar
  13. Hamilton PM, Varey RH, Millán MM (1978) Remote sensing of sulphur dioxide. Atmos Environ 12:127–207Google Scholar
  14. Harris DM, Sato M, Casadevall TJ, Rose WI, Bornhorst TJ (1981) Emission rates of CO2 from plume measurements. In: Lipman PW, Mullineaux DR (eds) The 1980 Eruptions of Mount St. Helens, Washington. US Geol Surv Prof Pap 1250:201–207Google Scholar
  15. Malinconico LL (1979) Fluctuations in SO2 emission during recent eruptions of Etna. Nature 278:43–45Google Scholar
  16. Malone SD, Frank D (1975) Increased heat emission from Mount Baker, Washington. EOS 56:679–685Google Scholar
  17. McGee KA (1992) The structure, dynamics, and chemical composition of noneruptive plumes from Mount St. Helens, 1980–88. J Volcanol Geotherm Res 51:269–282Google Scholar
  18. McGee KA, Sutton AJ (1990) A detailed study of the USGS reducing-gas sensor with field tests at Long Valley, California. US Geol Surv Open File Rep 90–61:1–68Google Scholar
  19. Mellors RA, Waitt RB, Swanson DA (1988) Generation of pyroclastic flows and surges by hot-rock avalanches from the dome of Mount St. Helens volcano, U.S.A. Bull Volcanol 50:14–25Google Scholar
  20. Millán MM, Hoff RM (1978) Remote sensing of air pollutants by correlation spectroscopy — instrumental response characteristics. Atmos Environ 12:853–864Google Scholar
  21. Millán MM, Gallant AJ, Turner HE (1976) The application of correlation spectroscopy to the study of dispersion from tall stacks. Atmos Environ 10:499–511Google Scholar
  22. Murray TL (1988) A system for telemetering low-frequency data from active volcanoes. US Geol Surv Open File Rep 88-201: 1–28Google Scholar
  23. Rose WI, Chuan RL, Kyle PR (1985) Rate of sulphur dioxide emission from Erebus volcano, Antarctica. Nature 316:710–712Google Scholar
  24. Sato M, McGee KA (1981) Continuous monitoring of hydrogen on the south flank of Mount St. Helens. In: Lipman PW, Mullineaux DR (eds) The 1980 Eruptions of Mount St. Helens, Washington. US Geol Surv Prof Pap 1250:209–219Google Scholar
  25. Sato M, Malone SD, Moxham RM, McLane JE (1976) Monitoring of fumarolic gas at Sherman Crater, Mount Baker, Washington. EOS 57:88–89Google Scholar
  26. Stoiber RE, Malinconico LL, Williams SN (1983) Use of the correlation spectrometer at volcanoes. In: Tazieff H, Sabroux JC (eds) Forcasting Volcanic Events. Elsevier, Amsterdam, pp 425–444Google Scholar
  27. Sutton AJ, McGee KA (1989) A multiple-species volcanic gas sensor — testing and applications [abstract]. IAVCEI Continental Magmatism General Assembly, Santa Fe, New Mexico, p 262Google Scholar
  28. Sutton AJ, McGee KA, Casadevall TJ, Stokes JB (1992) Fundamental volcanic-gas-study techniques: an integrated approach to monitoring. In: Ewert JW, Swanson DA (eds) Monitoring Volcanoes: Techniques and Strategies Used by the Staff of the Cascades Volcano Observatory, 1980–90. US Geol Surv Bull 1966:181–188Google Scholar
  29. Swanson DA (1985) Graben formation, thrust faulting, and growth of the dacite dome, Mount St. Helens, Washington, May–June 1985. EOS 66:852Google Scholar
  30. Swanson DA, Dzurisin D, Holcomb RT, Iwatsubo EY, Chadwick WW, Casadevall TJ, Ewert JW, Heliker CC (1987) Growth of the lava dome at Mount St. Helens, Washington (USA), 1981–1983. In: Fink JH (ed) The Emplacement of Silicic Domes and Lava Flows. Spec Pap Geol Soc Am 212:1–16Google Scholar
  31. Williams SN, Stoiber RE, N Garcia P, A Londoño C, Gemmel JB, Lowe DR, Connor CR (1986) Eruption of Nevado del Ruiz volcano, Colombia, on 13 November, 1985: gas flux and fluid geochemistry. Science 233:964–967Google Scholar

Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • K. A. McGee
    • 1
  • A. Jefferson Sutton
    • 2
  1. 1.US Geological SurveyCascades Volcano ObservatoryVancouverUSA
  2. 2.US Geological Survey, Hawaiian Volcano ObservatoryHawaii National ParkUSA

Personalised recommendations