Eruption chronologies, plume heights and eruption styles at Tungurahua Volcano: Integrating remote sensing techniques and infrasound

Satellite remote sensing allows volcanic ash plumes to be detected and tracked and routinely aids in hazard mitigation, especially to the aviation community. Although satellite imagery provides valuable information about volcanic plume processes (i.e. plume heights, plume composition and plume transport), it has its limitations. In addition to the observational gaps produced by meteorological clouds as well as temporal and spatial resolution restrictions, large volcanic clouds often obscure the vent during an eruption. Therefore, some key information about eruption dynamics and processes are impossible to obtain from satellite images. In this paper we investigate four eruptions at Tungurahua Volcano, Ecuador during the 2006–2008 time period. We integrate satellite-derived eruption chronologies, plume heights and plume aspect ratios with infrasound data, primarily acoustic power and hand-held thermal imagery when available. Integrating these datasets allows us to identify accurate eruption onsets, durations and cessations as well as define different types of eruption styles ranging from plinian to weak vulcanian. Transitions between the different eruption styles were also documented. Results show that there is a positive correlation between plume height and acoustic power. We conclude that combining the two datasets allows better constraints on eruption processes and source parameters. Using these methods in real-time monitoring will allow more accurate eruption monitoring and ash hazard mitigation.