The Influence of Episodic Shallow Magma Degassing on Heat and Chemical Transport in Volcanic Hydrothermal Systems Academic Article uri icon

abstract

  • AbstractSprings at La Soufrire of Guadeloupe have been monitored for nearly four decades since the phreatic eruption and associated seismic activity in 1976. We conceptualize degassing vapor/gas mixtures as squarewave sources of chloride and heat and apply a new semianalytic solution to demonstrate that chloride and heat pulses with the same timing and duration result in good matches between measured and simulated spring temperatures and concentrations. While the concentration of chloride pulses is variable, the local boiling temperature of 96C was assigned to all thermal pulses. Because chloride is a conservative tracer, chloride breakthrough is only affected by onedimensional advection and dispersion. The thermal tracer is damped and lagged relative to chloride due to conductive heat exchange with the overlying and underlying strata. Joint analysis of temperature and chloride allows estimation of the onset and duration of degassing pulses, refining the chronology of recent magmatic intrusion.

published proceedings

  • GEOPHYSICAL RESEARCH LETTERS

author list (cited authors)

  • Chen, K., Zhan, H., Burns, E. R., Ingebritsen, S. E., & Agrinier, P.

citation count

  • 4

complete list of authors

  • Chen, Kewei||Zhan, Hongbin||Burns, Erick R||Ingebritsen, Steven E||Agrinier, Pierre

publication date

  • April 2018