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1. Hands on Rock Weathering!

   https://doi.org/10.1080/08872376.2025.2478798  

   Nutt, Mara; Scheingross, Joel; Beckam, Megan (May 2025, Science Scope)

   In the Earth sciences, weathering encompasses all the physical, chemical, and biological processes that break down rocks in place. Rock weathering takes decades to millions of years and impacts climate and soil formation. In our two-part lesson, students develop an understanding of weathering and how it can influence climate and human society through hands-on experiments. Lesson 1 focuses on how rock weathering impacts climate; students investigate how changing the temperature and acidity of weathering agents affects the rate of rock weathering. Lesson 2 focuses on how weathering impacts human society; students perform experiments simulating weathering of mudstone and granite via shaking rocks in containers; students observe that these rocks weather at different rates and produce different-sized particles because of physical weathering. Students relate their experimental observations to the process of soil formation and then apply this knowledge to societally relevant topics. These lessons bring rock weathering into the classroom with crosscutting concepts and connect the Earth, climate, and human society together in an interactive way. 

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2. Fine-regolith production on asteroids controlled by rock porosity

   https://doi.org/10.1038/s41586-021-03816-5  

   Cambioni, S.; Delbo, M.; Poggiali, G.; Avdellidou, C.; Ryan, A. J.; Deshapriya, J. D.; Asphaug, E.; Ballouz, R.-L.; Barucci, M. A.; Bennett, C. A.; et al (October 2021, Nature)
3. EFFECT OF WATER-ROCK RATIO ON THE STABLE ISOTOPE RECORD OF FLUID-ROCK-DEFORMATION INTERACTIONS IN DETACHMENT SHEAR ZONES

   https://doi.org/10.1130/abs/2023AM-394184  

   Gottardi, Raphael; Mire, Camron; Davis, Niya (January 2023, Geological Society of America Abstracts with Programs)
4. Effect of Water‐Rock Ratio on the Stable Isotope Record of Fluid‐Rock‐Deformation Interactions in Detachment Shear Zone

   https://doi.org/10.1029/2023GC011340  

   Gottardi, Raphaël; Mire, Camron; Davis, Niya; Casale, Gabriele (May 2024, Geochemistry, Geophysics, Geosystems)

   Abstract Oxygen and hydrogen stable isotope analyses of quartz and muscovite veins from the footwall of the Raft River detachment shear zone (Utah) provide insight into the hydrology and fluid‐rock interactions during ductile deformation. Samples were collected from veins containing 90%–100% quartz with orientations either at a high angle or sub‐parallel to the surrounding quartzite mylonite foliation. Stable isotope analysis was performed on 10 samples and compared with previous quartzite mylonite isotope data sets. The results indicate that the fluid present during deformation of the shear zone was meteoric in origin, with a δ²H value of approximately −100‰ and a δ¹⁸O value of approximately −13.7‰. Oxygen stable isotope O¹⁸O depletion correlates with the muscovite content of the analyzed rocks. Many of the analyzed samples in this and other studies show an apparent lack of equilibrium between the oxygen and hydrogen isotope systems, which can be explained by hydrogen and oxygen isotope exchange at varying fluid‐rock ratios. Our results suggest that the Raft River detachment shear zone had a low static fluid‐rock ratio (<0.1), yet experienced episodic influxes of fluids through semi‐brittle structures. This fluid was then expelled out into the surrounding mylonite following progressive shearing, causing further¹⁸O‐depletion and fluid‐related embrittlement. 

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5. Meteorological Controls on Reversible Resonance Changes in Natural Rock Arches

   https://doi.org/10.1029/2022JF006734  

   Geimer, Paul R.; Finnegan, Riley; Moore, Jeffrey R. (October 2022, Journal of Geophysical Research: Earth Surface)

   Abstract Continuous ambient seismic monitoring is becoming common for structural health assessment of geologic features. However, the ability to detect or predict permanent mechanical change associated with damage requires detailed understanding of reversible drifts in resonance attributes associated with changing meteorological conditions. Here, we analyze the response of 17 sandstone rock arches to changing meteorological conditions during extended vibration‐based monitoring, with a focus on 1 arch in Utah which was continuously monitored for 15 months. Our results show that variations in resonance are correlated with temperature on daily and yearly time scales, but that the temperature sensitivity of frequency changes are variable at different sites and resonance modes, generally ranging from 0.5% to 6% per 10°C. Numerical modeling suggests the primary mechanism governing these frequency drifts is stress stiffening, where confined thermal dilation induces bulk stress changes in the low‐stress, nonlinear elastic regime via fracture closure. Secondary mechanisms affecting resonance attributes are driven by moisture, including formation of shallow pore ice, which can generate sharp frequency changes of up to 17% per −10°C, and moisture‐induced softening. Daily lag times of several hours between temperature and frequency extrema provide constraints on the rock volumes affected by these mechanisms, indicating modal attributes are sensitive to thermally driven changes occurring in the outermost centimeters of the structure. Through improved understanding of the reversible variations of rock mass resonance, our results aid future assessment of irreversible frequency changes associated with damage, and thus structural health monitoring of fragile geologic features. 

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