Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by McGee, K. A. Articles by Gerlach, T. M. Search for Related Content GeoRef GeoRef Citation

Annual cycle of magmatic CO₂ in a tree-kill soil at Mammoth Mountain, California: Implications for soil acidification

¹ U.S. Geological Survey, Cascades Volcano Observatory, Vancouver, Washington 98661-7095

Time-series sensor data reveal significant short-term and seasonal variations of magmatic CO₂ in soil over a 12 month period in 1995–1996 at the largest tree-kill site on Mammoth Mountain, central-eastern California. Short-term variations leading to ground-level soil CO₂ concentrations hazardous and lethal to humans were triggered by shallow faulting in the absence of increased seismicity or intrusion, consistent with tapping a reservoir of accumulated CO₂, rather than direct magma degassing. Hydrologic processes closely modulated seasonal variations in CO₂ concentrations, which rose to 65%–100% in soil gas under winter snowpack and plunged more than 25% in just days as the CO₂ dissolved in spring snowmelt. The high efflux of CO₂ through the tree-kill soils acts as an open-system CO₂ buffer causing infiltration of waters with pH values commonly of <4.2, acid loading of up to 7 keq_H+ha^–1yr^–1, mobilization of toxic Al³⁺, and long-term decline of soil fertility.

This article has been cited by other articles:

				A. J. S. McGonigle and C. Oppenheimer Optical sensing of volcanic gas and aerosol emissions Geological Society, London, Special Publications, January 1, 2003; 213(1): 149 - 168. [Abstract] [PDF]

				L. J. Wardell, P. R. Kyle, and A. R. Campbell Carbon dioxide emissions from fumarolic ice towers, Mount Erebus volcano, Antarctica Geological Society, London, Special Publications, January 1, 2003; 213(1): 231 - 246. [Abstract] [PDF]