ISTerre seminar

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Imaging and Monitoring the Yellowstone Magma Reservoir using Waterfall Noise

Tuesday 17 March 2026 - 11h00

HyeJeong Kim - GeoAzur
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Understanding of the physical state of the Yellowstone magma reservoir has significantly improved in recent years, thanks to the improved seismic data coverage in the area. In particular, the mushy magmatic reservoir and its sharp top boundary have been imaged by ambient noise surface waves and active source body waves with unprecedented resolution in recent studies. Despite their success, continuous monitoring of temporal variations in the structure of the top boundary layer remains challenging, as standard passive body wave analysis, such as teleseismic receiver functions, often suffers from extreme waveform complexity due to scattering and off-great-circle bending. In this study, we analyze passive seismic signals recorded by the Yellowstone seismic network and by a one-month dense geophone array deployed in 2020. We show that body waves excited by the Upper and Lower Yellowstone Falls can be extracted through noise cross-correlation, where both P and S waves traveling above the magma reservoir and the P wave reflected off the top of the magma reservoir can be observed. Moreover, we perform teleseismic coda autocorrelation, which allows constraints on the bottom of the magma reservoir. The velocities and the depth to the reflection are consistent with the recent active source and ambient noise studies. Taking advantage of persistent waterfall energy, we investigate the long-term temporal variation of the reflected P-wave signal using permanent stations. A gradual increase in the time delay is observed between 2008 and 2015, which correlates with the change in vertical surface ground movement observed by GNSS stations near the Yellowstone Caldera. Our results present a novel approach for imaging and monitoring the Yellowstone magma body using passive seismic data.

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Organizing team : Ondes et structures

Amphithéâtre Killian, Maison des Géosciences, 38400 Saint Martin d'Hères

Informations de visio :

https://univ-grenoble-alpes-fr.zoom.us/j/95496607088?pwd=UuSVyVX0SCxaFwJ8BOzQujEfEjydwi.1