Article
Geosciences, Multidisciplinary
Greg A. Valentine, Judy Fierstein, James D. L. White
Summary: Hazard assessments in monogenetic volcanic fields should consider the long runout distance of phreatomagmatic surges. The deposits at Ubehebe Crater provide valuable evidence for long-distance runout. Numerical simulations show that low temperatures facilitate long runout for cool surges.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Geoffrey A. Lerner, Susanna F. Jenkins, Sylvain J. Charbonnier, Jean-Christophe Komorowski, Peter J. Baxter
Summary: Unconfined pyroclastic density currents (PDCs) are highly dangerous volcanic hazards that can cause significant impacts on inhabited areas. Previous studies have only described a limited number of specific cases of unconfined PDCs. In this study, a comparative analysis is conducted to review the different types of unconfined PDCs, their characteristics, dynamics, and impacts, emphasizing the importance of accounting for these phenomena in emergency management and planning at active volcanoes.
JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Hiroyuki A. Shimizu, Takehiro Koyaguchi, Yujiro J. Suzuki, Ermanno Brosch, Gert Lube, Matteo Cerminara
Summary: In this study, a two-layer depth-averaged model was used to numerically simulate pyroclastic density currents (PDCs) with stratification of particle concentrations. Results showed that the thickness of the suspended load and bed-load in the simulations depend on the settling speed at the bottom of the bed load. By setting the settling speed to a specific value, the simulated thicknesses of bed load and deposit matched well with experimental data.
BULLETIN OF VOLCANOLOGY
(2021)
Article
Construction & Building Technology
Minju Kim, Su-Gwang Jeong, Jongil Park, Sumin Kim, Jeong-Hun Lee
Summary: The relationship between PM and ambient humidity was evaluated through two experiments based on chemical composition and PM particle size analysis. The results showed that indoor PM concentrations were effectively decreased and prevented from spreading when the indoor relative humidity was above a certain threshold. However, increasing airtightness to increase indoor relative humidity may not be a practical solution in all cases.
BUILDING AND ENVIRONMENT
(2023)
Review
Geosciences, Multidisciplinary
Thomas J. Jones, Frances Beckett, Benjamin Bernard, Eric C. P. Breard, Fabio Dioguardi, Josef Dufek, Samantha Engwell, Julia Eychenne
Summary: This article emphasizes the importance of the physical properties of pyroclastic density current (PDC) deposits for hazard assessment and risk management. It discusses the challenges associated with measuring and characterizing these properties, as well as emerging topics and future research directions in the field.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Materials Science, Coatings & Films
Jaeuk Lee, Kshitiz Kumar Subedi, Gordon W. Huang, Jonghyun Lee, Song-Charng Kong
Summary: Coating technologies, such as thermal spray, can enhance the durability and lifespan of mechanical components by rebuilding damaged surfaces. In this study, the Smoothed Particle Hydrodynamics (SPH) method is used to investigate the impact of droplets on substrates under thermal spray conditions. The results show that the impact velocity and substrate temperature play a crucial role in the formation of deposition splat.
JOURNAL OF THERMAL SPRAY TECHNOLOGY
(2022)
Article
Chemistry, Physical
Ying-Guang Fang, Hao Liu, Ling-Feng Guo, Xiao-Long Li, Pei-Xu Wang, Ren-guo Gu
Summary: This paper establishes equations for calculating the sedimentation potential of complex particle systems and considers multifactorial coupling effects. The equations have substantial value in controlling particle behavior and discovering sedimentation potential characteristics of uniform particle systems.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Soil Science
M. Beczek, M. Ryzak, A. Sochan, R. Mazur, C. Polakowski, A. Bieganowski
Summary: This study aims to present an improved method for calculating the kinetic energy of splashed material by measuring key parameters that influence particles' energy. Various methodologies were used to obtain data on the ejected particles, including their mass, velocity, and density. Three variants of kinetic energy calculation were tested, with the results showing that the total kinetic energy of splashed particles ranged between 4.6% and 7.4% of the kinetic energy of the impacting water drop.
Article
Geosciences, Multidisciplinary
Karim Kelfoun, Valentin Gueugneau
Summary: This article presents a model that explains the mechanisms behind the formation and flow of pyroclastic density currents. It highlights the significance of topography in understanding and predicting the destructive capacity of these volcanic phenomena.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Agricultural Engineering
Minna Jiao, Xiuna Ren, Yifeng He, Juan Wang, Cuihuan Hu, Zengqiang Zhang
Summary: In order to clarify the impact of particle size of bulking agents on humification and the relevant mechanisms, different lengths (<2 cm, 2 cm, 5 cm, 10 cm) of branch and straw were individually blended with swine manure for 100 days of aerobic composting. The results showed that 2 cm and 5 cm of branch and straw had the highest degradation rates of DOC, increasing the humic substances in the maturity stage by 41.49% and 58.42% respectively, compared to the other treatments. Microbial analysis confirmed the increase in humic fungi abundance in the 2 cm and 5 cm treatments, further supporting the variation in humus content. In conclusion, particle size has a significant impact on humification, with the optimized sizes being around 2 cm and 5 cm for branch and straw.
BIORESOURCE TECHNOLOGY
(2023)
Article
Mechanics
A. Sankaran, J. Wu, R. Granda, V Yurkiv, F. Mashayek, A. L. Yarin
Summary: This study experimentally investigates the electrohydrodynamics of drop impact onto a dielectric surface with embedded electrodes, demonstrating that the application of electric field can significantly enhance drop spreading on non-wettable surfaces, suppress water drop rebound, and partially suppress splash phenomena. Comparisons with simulations show close agreement for water drops, suggesting that electrowetting-on-dielectric holds great promise for coating and spraying technologies.
Article
Thermodynamics
Yaoyu Pan, Xiufeng Yang, Song-Charng Kong, Foo Chern Ting, Claudia Iyer, Jianwen Yi
Summary: Accurately predicting the outcome of drop/wall interaction is crucial for engine spray combustion modeling. The study used a numerical method based on smoothed particle hydrodynamics to simulate the impact process of fuel droplets on wet walls. The results showed that the presence of a wall film affects splash threshold, crown evolution, and the generation of secondary droplets.
INTERNATIONAL JOURNAL OF ENGINE RESEARCH
(2022)
Article
Pharmacology & Pharmacy
William C. Smith, Jungeun Bae, Ying Zhang, Bin Qin, Yan Wang, Darby Kozak, Muhammad Ashraf, Xiaoming Xu
Summary: Variation in injection method can alter the particle state and dissolution rate of triamcinolone acetonide suspensions, potentially impacting drug bioavailability. Study also shows that deflocculated particles dissolve significantly faster than flocculated particles, highlighting the importance of shear-induced changes during injection on drug dissolution and bioavailability.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2021)
Article
Agriculture, Dairy & Animal Science
Amr Abd El-Wahab, Richard Grone, Volker Wilke, Marwa F. E. Ahmed, Bussarakam Chuppava, Christian Visscher, Josef Kamphues
Summary: This study aimed to investigate the physio-chemical properties of wheat, hybrid rye, and barley, and found significant differences in particle size distribution at different screen sizes. Hybrid rye had the largest particles >1.0 mm, while wheat had the lowest water holding capacity. Additionally, hybrid rye exhibited high extract viscosity compared to wheat and barley.
ITALIAN JOURNAL OF ANIMAL SCIENCE
(2021)
Article
Chemistry, Physical
Jaspreet Singh, Alison E. Patteson, Bryan O. Torres Maldonado, Prashant K. Purohit, Paulo E. Arratia
Summary: Sedimentation of passive particles in active fluids is greatly influenced by the presence of swimming bacteria, which slows down the sedimentation speed and increases particle dispersion. In short timescales, there is a linear relationship between bacterial concentration and particle sedimentation speed, but bacterial activity decays over longer experimental times. An advection-diffusion equation coupled with bacteria population dynamics can fairly accurately predict concentration profiles in this scenario.
Article
Geosciences, Multidisciplinary
Maxwell L. Rudolph, Michael Manga, Matthew Walker, Alyssa R. Rhoden
Summary: The evolution of ice-covered ocean worlds like Europa and Enceladus is closely related to their orbital and internal changes, which can lead to the formation of cracks and eruptions. However, cracks do not penetrate the ice shell of Europa due to its ice tensile strength, while the varying thickness and tidal dissipation of the ice shell on Enceladus allow cracks to cross it and result in eruptions from the ocean.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Amy Ferrick, Vanshan Wright, Michael Manga, Nicholas Sitar
Summary: The orientation and contact between sand grains can reflect the deposition processes and influence mechanical properties. Comparing the microstructure of naturally-deposited beach sands and laboratory sands, it is found that they have different distribution of coordination number and grain orientations, which can be explained by the different depositional methods.
Article
Geosciences, Multidisciplinary
Benjamin A. Black, Michael Manga, Lujendra Ojha, Marc-Antoine Longpre, Suniti Karunatillake, Lisa Hlinka
Summary: Water inventories in Martian magmas are poorly understood, but using thorium as a proxy, this study finds that the water content in magmas during the Hesperian and Amazonian epochs is lower than previously estimated and consistent with Mars' present-day water inventory.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Environmental Sciences
W. J. Hahm, D. N. Dralle, M. Sanders, A. B. Bryk, K. E. Fauria, M. H. Huang, B. Hudson-Rasmussen, M. D. Nelson, M. A. Pedrazas, L. Schmidt, J. Whiting, W. E. Dietrich, D. M. Rempe
Summary: This study investigates the dynamics of water storage in bedrock and its implications for water availability and groundwater recharge. The findings show that in wet years, bedrock quickly replenishes water storage and recharges groundwater, while in drought years, water storage declines, resulting in water stress for woody plants.
WATER RESOURCES RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Maggie Zheng, Tushar Mittal, Kristen E. Fauria, Ajit Subramaniam, Martin Jutzeler
Summary: Most volcanic eruptions occur underwater, which can have significant impacts on Earth's systems. However, detecting submarine eruptions is challenging. This study develops a new framework using satellite imagery and analysis to detect and study submarine eruptions.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Vashan Wright, Jhardel Dasent, Richard Kilburn, Michael Manga
Summary: Ice and other mineral cements in Mars' shallow subsurface affect the mechanical properties of the shallow crust, the geologic processes that shape the planet's surface, and the search for past or extant Martian life. Cements increase seismic velocities. Rock physics models are used to infer cement properties from seismic velocities. Model results confirm that the upper 300 m of Mars beneath InSight is most likely composed of sediments and fractured basalts, with grains unlikely to be cemented by ice or other mineral cements. Fractures within the basalt layers could be filled with gas and a small percentage of mineral cement, but not ice or liquid water-saturated layers. Cement at grain contacts has likely been broken by impacts or marsquakes.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Environmental Sciences
Yan Zhang, Michael Manga, Li-Yun Fu, Qiu-Ye Yang, Zhen-Dong Cui, Yuan Huang
Summary: This study uses water level monitoring data from 5 deep wells on the North China Platform to investigate the impact of two large earthquakes on deep aquifers. The results show that a subset of these wells exhibit changes in the phase shifts of water level responses to lunar diurnal and semidiurnal tides after the passage of seismic waves. A model is used to explain these changes by proposing a change in the apparent orientation of fractures. It is suggested that this change occurs when the hydraulic connectivity of fracture networks is altered by the passage of seismic waves.
WATER RESOURCES RESEARCH
(2022)
Article
Geochemistry & Geophysics
Kristen E. Fauria, Martin Jutzeler, Tushar Mittal, Ashok Kumar Gupta, Liam J. Kelly, John Rausch, Ralf Bennartz, Brent Delbridge, Lise Retailleau
Summary: The eruption of Fukutoku-Oka-no-Ba on August 12, 2021, is a rare occurrence of a submarine volcano producing a large aerial plume and floating pumice raft. Satellite remote sensing was utilized to investigate the eruption timeline, style, rates, and products. The study revealed that the eruption plume was ice-rich and the pumice raft and plume were co-genetic, formed by the fallout of pumice lapilli from a water-rich eruption column.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Mara H. Reed, Michael Manga
Summary: Geyser and volcano monitoring suffer from biases related to time, location, and instrumentation. Through multiyear monitoring of Steamboat Geyser in Yellowstone National Park, we identified a recording bias. In winter, the eruption signals recorded at nearby seismometers had lower amplitudes, which were found to be influenced by environmental conditions rather than the source. The lower amplitudes were correlated with greater snow depths at a station 340 m away from Steamboat, and we calculated an energy attenuation coefficient of 0.21 ± 0.01 dB per cm of snow. Long-term monitoring of geysers is necessary to track changes over time and identify recording biases that may be missed during short, sporadic studies.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Cheng-Nan Liu, Fan-Chi Lin, Michael Manga, Jamie Farrell, Sin-Mei Wu, Mara H. H. Reed, Anna Barth, Jefferson Hungerford, Erin White
Summary: Doublet Pool is an active hydrothermal feature in Yellowstone National Park, USA. It thumps approximately every half hour for about 10 min due to collapsing bubbles. By studying hydrothermal tremors and linking them with the thumping, the researchers were able to determine the duration of silence between each thumping cycle and found that it decreased from 30 minutes to 13 minutes over time. They also discovered that unusual thermal activity on Geyser Hill and wind-driven evaporative cooling can affect the thumping behavior. Based on energy conservation, the heating rate and heat needed to initiate thumping were estimated to be 3-7 MW and approximately 6 GJ, respectively.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Review
Environmental Sciences
Chi-Yuen Wang, Michael Manga
Summary: The effects of earthquakes on groundwater and aquifer properties can be measured and monitored by analyzing water-level changes caused by tides and barometric pressure. Tidal and barometric responses are particularly useful in assessing the impacts of unexpected events like earthquakes since they are continuously generated and recorded over large areas. This article focuses on reviewing the hydrogeologic interpretations of these responses and their implications for earthquake-induced changes in aquifer confinement and permeability. It also emphasizes the value of long-term monitoring and analysis of earthquake response at multiple tidal and barometric frequencies.
Article
Geochemistry & Geophysics
Baptiste Penlou, Olivier Roche, Michael Manga, Siet van den Wildenberg
Summary: The dynamics of geophysical dilute turbulent gas-particles mixtures are influenced by particle concentration, which depends mainly on particle settling velocity. This study investigates air-particle mixtures in a vertical pipe where the ascending air flux matches the settling velocity of glass particles. The results show an interplay between hindered settling and cluster-induced enhanced settling, which have implications for volcanic plumes and pyroclastic currents.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
Shaul Hurwitz, John C. King, Gregory T. Pederson, Mara H. Reed, Lauren N. Harrison, Jefferson D. G. Hungerford, R. Greg Vaughan, Michael Manga
Summary: Most eruptions of Steamboat Geyser in the Norris Geyser Basin of Yellowstone National Park occurred in three episodes in the past century. These eruptions had a significant impact on the surrounding trees. Through the analysis of aerial and ground images, changes in tree coverage were documented since 1954 to understand the geyser's response to climate variability.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2023)
Article
Geochemistry & Geophysics
Liam J. Kelly, Kristen E. Fauria, Tushar Mittal, Jan El Kassar, Ralf Bennartz, David Nicholson, Ajit Subramaniam, Ashok Kumar Gupta
Summary: Volcanoes depositing eruptive products into the ocean can trigger phytoplankton blooms, but the specific conditions and mechanisms are not well understood. Using satellite remote sensing, this study analyzed the chlorophyll response to explosive and effusive activity from Nishinoshima volcano, Japan. The study found that the volcanic activity led to significant phytoplankton blooms, with a spatial correlation between blooms and ash plume direction. Based on nutrient supply, it is hypothesized that nitrogen-fixing phytoplankton led to a significant drawdown of carbon.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2023)
Article
Geochemistry & Geophysics
M. Colombier, M. Manga, H. Wright, B. Bernard, R. deGraffenried, F. Caceres, P. Samaniego, J. Vasseur, K. Jakata, P. Cook, D. B. Dingwell
Summary: Breadcrust bombs are volcanic ejecta formed during explosive volcanic eruptions, and the variations in porosity and vesicle properties from crust to interior shed light on the pre-eruptive conditions in the magma prior to explosive activity and on the post-fragmentation evolution of the bomb interior by bubble formation.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)