Séminaire ISTerre

Rocks, fluids and microorganisms – The weathering of silicate minerals across scales

samedi 26 octobre 2019 - 11h00
Bastien WILD - Princeton Univ.
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The chemical weathering of minerals is central to several open scientific questions including the long-term fate of atmospheric CO2, the renewal of soil nutrients pools, the release of metal contaminants and the biogeochemical cycling of elements in the critical zone1-3. However, the fundamental processes that control mineral reactivity remain incompletely understood, as illustrated by the long-standing inconsistency between field and laboratory estimates of dissolution kinetics4. This knowledge gap limits our ability to address some of the most pressing societal challenges regarding the safety of deep geological storage of nuclear wastes and CO25,6, the sustainable management of drinking water, forest and land resources, hazards associated to the stability of volcanic edifice and dome structures7 or the development of construction materials with reduced carbon footprints8. This seminar will highlight important rate-limiting processes occurring at the fluid-mineral-microorganism interface, which are generally overlooked by current kinetic models9,10. In particular, textural and structural changes taking place at the reaction interface can control mineral dissolution at several scales, as supported by our recent results from molecular dynamics, advanced electron microscopy and in-situ synchrotron techniques9,11. I will provide new insights from field experiments on the effect of microorganisms and preferential fluid flow pathways in soils on the dissolution rates of minerals. Subtle reciprocal relationships between mineral substrates and associated microbial communities revealed by these experiments will also be described2,12. Overall, this talk will emphasize key differences existing between average "bulk" properties, which are usually recorded in the field or in laboratory setups, and local biogeochemical environments actually driving mineral reactivity in-situ.

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

“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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