T.M. Gerlach K.A. McGee 1998 <div id="15578623" class="article-section-wrapper js-article-section js-content-section " data-section-parent-id="0"><p>Time-series sensor data reveal significant short-term and seasonal variations of magmatic CO₂<span>&nbsp;</span>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<span>&nbsp;</span>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<span>&nbsp;</span>concentrations, which rose to 65%–100% in soil gas under winter snowpack and plunged more than 25% in just days as the CO₂<span>&nbsp;</span>dissolved in spring snowmelt. The high efflux of CO₂<span>&nbsp;</span>through the tree-kill soils acts as an open-system CO₂<span>&nbsp;</span>buffer causing infiltration of waters with pH values commonly of &lt;4.2, acid loading of up to 7 keq_H+ṁha⁻¹ṁyr⁻¹, mobilization of toxic Al³⁺, and long-term decline of soil fertility.</p></div> application/pdf 10.1130/0091-7613(1998)026<0463:ACOMCI>2.3.CO;2 en Geological Society of America Annual cycle of magmatic CO2 in a tree-kill soil at Mammoth Mountain, California: Implications for soil acidification article