Preprints
Filtering by Subject: Earth Sciences
Algal lipid distributions and hydrogen isotope ratios reflect phytoplankton community dynamics
Published: 2025-01-20
Subjects: Earth Sciences, Geochemistry, Paleobiology, Physical Sciences and Mathematics, Sedimentology
Reconstructions of past changes in algal community composition provide important context for future alterations in biogeochemical cycling. However, many existing phytoplankton proxies are indicative of individual algal groups and are not fully representative of the whole community. Here, we evaluated hydrogen isotope ratios of algal lipids (δ2HLipid) as a potential proxy for phytoplankton [...]
Changes in physical properties of rocks during serpentinization and implications for natural hydrogen exploration
Published: 2025-01-18
Subjects: Earth Sciences, Geology, Geophysics and Seismology
Serpentinization, transforms the physical properties of ultramafic rocks, with significant implications for natural hydrogen exploration. This study compiles and analyzes over 1,000 samples from diverse geological settings to elucidate relationships between rock properties—such as density, seismic velocities, elastic moduli, porosity, and magnetic susceptibility—and the degree of [...]
Hypereutrophication, Hydrogen Sulfide, and Environmental Injustices: Mechanisms and Knowledge Gaps at the Salton Sea
Published: 2025-01-16
Subjects: Earth Sciences, Environmental Studies, Physical and Environmental Geography, Physical Sciences and Mathematics
The Salton Sea, California’s largest lake, is undergoing significant environmental degradation, which has adverse health effects on nearby rural communities, who are primarily Latinx and Torres Martinez Desert Cahuilla Indian. Over the past two decades, the lake’s water levels have steadily dropped. Water conditions in the Sea, characterized by low oxygen and high nutrient levels, favor the [...]
Readapting PhaseNet to Laboratory Earthquakes: AEsNet, a Robust Acoustic Emission Picker Illuminating Seismic Signatures of Different Fault Gouge Materials
Published: 2025-01-14
Subjects: Earth Sciences, Geophysics and Seismology
Laboratory acoustic emissions (AEs) represent microslip events analogous to small- scale earthquakes, providing valuable insights into the mechanics of frictional instabilities. With technological advancements in acoustic monitoring, thousands of AE waveforms can now be collected in minutes of experimental time, requiring efficient methods for their detection and analysis. In this study, we [...]
GelCam: Visualizing Episodic Sinking Particle Flux via a Polyacrylamide Gel-Based Sediment Trap
Published: 2025-01-10
Subjects: Biogeochemistry, Earth Sciences, Oceanography
While particle-intercepting traps remain a dominant method for quantifying the contribution of sinking particles to the biological carbon pump, fluxes are typically integrated over days to months. Observations of time-varying particle flux over shorter durations are very limited. To this end, we prototyped a camera system called “GelCam” which captures a rapid time-lapse image sequence of [...]
A semi-automated method for constructing three-dimensional models of complex fault networks
Published: 2025-01-10
Subjects: Earth Sciences, Geophysics and Seismology, Tectonics and Structure
Fault geometry and the connectivity between faults at depth are both important controls on the nucleation, propagation and arrest of earthquake rupture, so modelling these parameters accurately is essential to models of the earthquake cycle. However, simulations involving complex three-dimensional (3D) fault systems rarely explore the sensitivity of results to uncertainties in geometry and [...]
Hydrogenotrophic metabolisms in the subsurface and their implications for underground hydrogen storage and natural hydrogen prospecting
Published: 2025-01-08
Subjects: Biogeochemistry, Earth Sciences, Environmental Microbiology and Microbial Ecology Life Sciences, Oil, Gas, and Energy
Hydrogen is a fundamental electron donor in diverse microbial metabolisms and it is considered the energetic currency exchanged within microbial communities in anaerobic environments. Hydrogen is also the major actor in the transition to alternative low-carbon energy sources, primarily due to its dual role as energy source and energy carrier and to the production of water as a byproduct of its [...]
Grain size evolution in mantle convection models promotes continuous rather than episodic tectonics
Published: 2025-01-06
Subjects: Earth Sciences, Physical Sciences and Mathematics, Planetary Sciences
A long-persistent caveat of geodynamic models with Earth-like tectonic behavior is the need of an ‘ad hoc’ yield stress lower than any laboratory-inferred rock strength. Grain size reduction due to dynamic recrystallization provides local weak zones in the lithosphere thereby promoting lithospheric breakdown and continuous mobile-lid tectonics. Grain growth should instead (re-)strengthen the [...]
2027: Waking the AKU-- A Cosmic Hyperobject View of the Ancient Giant Palm Forest on Rapa Nui
Published: 2025-01-06
Subjects: Astrophysics and Astronomy, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Forest Sciences, Other Astrophysics and Astronomy, Other Environmental Sciences, Other Plant Sciences, Physical Sciences and Mathematics, Planetary Sciences, Plant Sciences, The Sun and the Solar System
Can a repeating climate event be termed as a cosmic hyperobject? Even if it is dynamically changing within hundreds of thousands of years? At the center of this paper is the science: observable data, 15,000 years of climate change on Rapa Nui. Reaching into the past however we begin with a much broader mathematical view from the eyes of Milankovitch theories of the cosmos that stretches a million [...]
Water Storage in Hydrous Minerals in the Shallow Martian Mantle
Published: 2025-01-06
Subjects: Earth Sciences, Geochemistry, Geology, Planetary Geochemistry
In this paper we investigate the possibility of storing water in the shallow martian mantle under water-saturated fluid absent conditions for different bulk silicate mars (BSM) compositions. We performed phase equilibria experiments on two BSM compositions with comparable Mg number for pressure between 2 and 4 GPa, temperatures between 950 to 1150°C, and for a water content of 0.3 % wt. The [...]
Techno-economic analysis of natural and stimulated geological hydrogen
Published: 2025-01-03
Subjects: Earth Sciences
Geological hydrogen has emerged as a low-cost and low-carbon primary source of energy. This study provides a comprehensive techno-economic analysis of natural geological hydrogen (GH) and stimulated geological hydrogen (SGH) production, reaffirming its potential as a low-cost energy source. For the United States, we estimate production costs at $0.54/kg for GH and $0.92/kg for SGH, demonstrating [...]
Is the Suez Rift in its post-rift phase?
Published: 2025-01-03
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Tectonics and Structure
Failed rifts are widely assumed to enter post-rift quiescence after termination of intracontinental rifting. However, this remains largely untested and a comprehensive evaluation of the rates and patterns of post-rift tectonic (in)activity is lacking. Our novel, rift-scale geomorphic analysis reveals “post-rift” rifting across the archetypal failed rift of Suez, in Egypt. Stacked topographic [...]
Sea level rise submergence simulations suggest substantial deterioration of Indian River Lagoon ecosystem services by 2050, Florida, U.S.A.
Published: 2025-01-03
Subjects: Climate, Earth Sciences, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Geology, Geomorphology, Natural Resources and Conservation, Natural Resources Management and Policy, Sustainability, Water Resource Management
The Indian River Lagoon is a 250-km long Estuary of National Significance located along the east central Florida coast of the USA. NOAA tidal records generated at a station located in the central reaches of the estuary indicate sea level rise has accelerated over the past 20 years to an average of 9.6 ± 1.6 mm yr−1 (2003–2022) and it is expected to continue accelerating over the duration of this [...]
L-Band Radiometric Measurement of Liquid Water in Greenland's Firn: Comparative Analysis with In Situ Measurements and Modeling
Published: 2024-12-31
Subjects: Earth Sciences, Glaciology
The addition and refreezing of liquid water to Greenland's accumulation area are increasingly important processes for assessing the ice sheet’s present and future mass balance, but uncertain initial conditions, complex infiltration physics, and limited field data pose challenges. Satellite-based L-band radiometry offers a promising new tool for observing liquid water in the firn layer, although [...]
Chromium Isotopes: A Window into Atmospheric Oxygenation
Published: 2024-12-31
Subjects: Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology
Chromium (Cr) isotopes are pivotal proxies for understanding Earth’s atmospheric oxygenation history. This review highlights δ53Cr signatures as tools for reconstructing redox dynamics during events like the Great Oxidation Event (GOE) and the Neoproterozoic Oxygenation Event (NOE). Advances in analytical techniques, particularly multi-collector inductively coupled plasma mass spectrometry [...]