Séminaire ISTerre


Imaging and Monitoring the Yellowstone Magma Reservoir using Waterfall Noise

mardi 17 mars 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.

Equipe organisatrice : 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


“Minimalist seismology”: studying earthquakes with sparse instrumentation

jeudi 17 septembre 2026 - 11h00

Mathieu Causse - ISTerre

Equipe organisatrice : Organisation labo

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

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Stable‑to‑dynamic expansion of fault slipping area through fluid injection observed in laboratory experiments using a sub‑meter scale specimen

vendredi 18 septembre 2026 - 14h00

Takatoshi Ito  - Université de Tohoku, Japan

Equipe organisatrice : Mécanique des failles

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

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Tectonics, Mantle Dynamics and Coupled Lithosphere-Mantle-Core Evolution of Earth and Other Rocky Worlds

jeudi 24 septembre 2026 - 11h00

Paul Tackley - ETH Zurich

Equipe organisatrice : Grands Séminaires ISTerre

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

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Tectonics, Mantle Dynamics and Coupled Lithosphere-Mantle-Core Evolution of Earth and Other Rocky Worlds

jeudi 24 septembre 2026 - 11h00

Paul Tackley - ETH Zurich

Equipe organisatrice : Grands Séminaires ISTerre

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

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Apport des expériences analogiques pour la modélisation et le suivi en temps réel de la propagation du magma en profondeur : Exemple du Rift Est Africain

jeudi 1er octobre 2026 - 11h00

Virginie Pinel - ISTerre

Equipe organisatrice : Organisation labo

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

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A t-on encore besoin de plaques pour expliquer la tectonique de la vallée du Rhône et des Alpes Occidentales ?

vendredi 2 octobre 2026 - 11h00

philippe VERNANT - Geosciences Montpellier

Equipe organisatrice : Tectonique active et sismicité

Salle Dolomieu, Maison des Géosciences, 38400 Saint Martin d'Hères

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TBA

vendredi 2 octobre 2026 - 14h00

Hugo Boulze - 

Equipe organisatrice : Cycle sismique et déformations transitoires

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

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TBA

vendredi 9 octobre 2026 - 11h00

Eric Beaucé - ISTerre

Equipe organisatrice : Cycle sismique et déformations transitoires

Salle Dolomieu, Maison des Géosciences, 38400 Saint Martin d'Hères

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TBA

vendredi 20 novembre 2026 - 11h00

Farzaneh Mohammadi - ENS Paris

Equipe organisatrice : Cycle sismique et déformations transitoires

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

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