Preprints
Filtering by Subject: Geophysics and Seismology
Low computational cost stochastic Gassmann fluid substitution modelling of hydrogen and carbon dioxide in clastic storage reservoirs
Published: 2025-03-06
Subjects: Geology, Geophysics and Seismology
The ability to safely store non-hydrocarbon fluids in the subsurface, such as carbon dioxide or hydrogen, will likely be vital in all pathways to decarbonise global energy systems. Storage of these fluids will require monitoring programmes to identify dynamic changes during the injection and storage phases and to identify unintended migration. Seismic monitoring is widely adopted in monitoring [...]
Magnetotelluric source amplitude effect
Published: 2025-03-04
Subjects: Earth Sciences, Geophysics and Seismology
Challenges and Opportunities in Cryosphere in the Hindu Kush Himalaya
Published: 2025-03-04
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Physical Sciences and Mathematics
The Hindu Kush Himalaya cryosphere faces critical challenges from climate change, including rapid glacier melt and reduced snow cover. These changes threaten water resources, ecosystems, and livelihoods across the region. However, opportunities emerge through advanced monitoring technologies and increased scientific understanding. Improved remote sensing and field observations allow better [...]
Seismic imaging of mid-crustal heterogeneity beneath geothermal systems, central Taupo Volcanic Zone, New Zealand
Published: 2025-02-26
Subjects: Earth Sciences, Geophysics and Seismology
The Taupo Volcanic Zone (TVZ) in New Zealand is a region of highly pro- ductive Quaternary volcanism and very large hydrothermal heat flux. Here we investigate the upper- and mid-crustal seismic velocity structure of a region within the central, rhyolitic part of the TVZ encompassing the high- temperature geothermal systems Mokai, Wairakei, Ng¯a Tamariki, Orakei Korako, Te Kopia and Rotokawa. [...]
Phytoplankton blooms in the new Southern Ocean sea ice regime
Published: 2025-02-24
Subjects: Biogeochemistry, Geophysics and Seismology, Oceanography
Over the last decade, the Antarctic sea ice extent has recorded record highs and lows. The anomalous low in 2023 suggested a new reduced sea-ice state, with unknown impacts on phytoplankton blooms, including phenology and magnitude. Analysing both Biogeochemical (BGC) and Core Argo floats, we compare annual sea ice extent (SIE) anomalies and sea ice volume (SIV) to physical and biological [...]
Quantitative assessment of tomographic proxies for lowermost mantle composition and mineralogy
Published: 2025-02-14
Subjects: Geophysics and Seismology
Large low velocity provinces (LLVPs) dominate the lowermost mantle, but their detailed thermochemical nature remains a topic of discussion. Particularly, it is unclear to what extent the bridgmanite to post-perovskite phase transition is able to explain their velocity characteristics. Robust constraints on the origin of these seismic structures would shed light on large-scale dynamic processes in [...]
A New Interpretation of Ptolemy's Germania Magna: Employing Computer-Assisted Image Distortion of a Medieval Map by Donnus Nicolaus Germanus to Examine Post-Glacial Geodynamics in Europe
Published: 2025-02-02
Subjects: Geology, Geomorphology, Geophysics and Seismology, Nature and Society Relations, Other Astrophysics and Astronomy, Other Earth Sciences, Other Geography, Other Planetary Sciences, Planetary Geology, Planetary Geomorphology, Planetary Geophysics and Seismology, Stratigraphy, Tectonics and Structure, The Sun and the Solar System
This paper revisits Claudius Ptolemy's depiction of Germania Magna through a multidisciplinary approach, integrating computer-aided distortion analysis of Donnus Nicolaus Germanus's medieval cartography with geological insights. The study proposes that the region underwent significant and complex transformations, likely influenced by tectonic activity, such as the reactivation of the Caledonian [...]
Quantifying Changes in Water Loading in the U.S. Southwest via Comparison of GNSS, GRACE, and SWE Datasets
Published: 2025-01-31
Subjects: Geophysics and Seismology, Hydrology
The synthesis of Gravity Recovery and Climate Experiment (GRACE) gravimetry data and Global Navigation Satellite System (GNSS) displacement data provides improved models of surface water hydrology. Much work remains to be done to understand the hydrological signal present in complementary geodetic data in much of the Western U.S., especially the Colorado River basin which comprises a diversity of [...]
Large earthquakes are more predictable than smaller ones
Published: 2025-01-29
Subjects: Geophysics and Seismology, Physical Sciences and Mathematics
Large earthquakes have been viewed as highly chaotic events regardless of their magnitude, making their prediction intrinsically challenging. Here, we develop a mathematical tool to incorporate multiscale physics, capable of describing both deterministic and chaotic systems, to model earthquake rupture. Our findings suggest that the chaotic behavior of seismic dynamics, that is, its sensitivity [...]
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 [...]
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 [...]
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 [...]
Euler inversion: Locating sources of potential-field data through inversion of Euler's homogeneity equation
Published: 2024-12-19
Subjects: Geophysics and Seismology, Numerical Analysis and Scientific Computing
Earth scientists can estimate the depth of certain rocks beneath Earth's surface by measuring the small disturbances that they cause in the Earth's gravity and magnetic fields. A popular method for this is Euler deconvolution, which is widely available in geoscience software and can be run quickly on a standard computer. Unfortunately, Euler deconvolution has some shortcomings: 1) the approximate [...]
Leaky faults modulated magma ascent and seismicity during the 2022 São Jorge (Azores) volcanic unrest
Published: 2024-12-17
Subjects: Earth Sciences, Geophysics and Seismology, Tectonics and Structure, Volcanology
Understanding the signatures and mechanisms of failed volcanic eruptions is vital for mapping magma plumbing systems and forecasting volcanic hazards. Geological structures like fractures and faults are key to guiding magma, but their mechanisms remain unclear due to limited 3-D mapping of faults in volcanic regions and sufficiently precise earthquake locations. The triple-junction setting of the [...]
Evidence for large disturbances of the Ediacaran geomagnetic field from West Africa
Published: 2024-11-27
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Constraining the paleogeography of the Ediacaran is crucial for understanding the extensive tectonic, biological and geochemical changes that occurred during that epoch. Paleomagnetism is an essential tool for reconstructing the Ediacaran paleogeography but it is complicated because the paleomagnetic data of that age display unusually fast and large directional oscillations. Two main competing [...]