Preprints
Filtering by Subject: Geophysics and Seismology
Robust directional analysis of magnetic microscopy images using non-linear inversion and iterative Euler deconvolution
Published: 2025-03-30
Subjects: Geophysics and Seismology
The first step in scientific data acquisition often involves analyzing entire samples, providing only a general characterization of the material. Enhancing data acquisition by improving spatial resolution and isolating the underlying phenomena contributing to the overall signal has become a central direction in various scientific fields. In paleomagnetism, this advancement is now possible with [...]
The complex rupture evolution of the long and slow, tsunamigenic 2021 South Sandwich Islands earthquake
Published: 2025-03-28
Subjects: Geophysics and Seismology
On August 21, 2021 a large earthquake occurred in the South Sandwich subduction zone, and the associated tsunami was widely observed. In order to robustly analyse the detailed seismic source process of this long-source duration (over 200 s) event occurring in a convexly shaped subduction zone, we applied the Potency Density Tensor Inversion with a non-rectangular and non-planar source surface to [...]
Fully-dynamic seismic cycle simulations in co-evolving fault damage zones controlled by damage rheology
Published: 2025-03-27
Subjects: Geophysics and Seismology
Both short-term coseismic off-fault damage and long-term fault growth during interseismic periods have been suggested to contribute to the formation and evolution of fault damage zones. Most previous numerical models focus on simulating either off-fault damage in a single earthquake or off-fault plasticity in seismic cycles ignoring changes of elastic moduli. Here we developed a new method to [...]
First-order Control Factors for Ocean-bottom Ambient Seismology Interferometric Observations
Published: 2025-03-24
Subjects: Geophysics and Seismology
Expanding the lower-frequency band of seismic energy sources, particularly below 2.0~Hz, is crucial for improving the stability and effectiveness of full waveform inversion (FWI). Conventional active sources including airguns are ineffective at generating low-frequency wavefields, while ambient seismic wavefields, driven by natural energy sources such as ocean waves, offer a promising [...]
Ocean-bottom Seismic Interferometry in Coupled Acoustic-Elastic Media
Published: 2025-03-24
Subjects: Geophysics and Seismology
Green’s function expressions for seismic interferometry in acoustic and elastic media have been extensively studied and applied across a wide range of applications, including surface-wave tomography and generating virtual shot gathers. However, analogous expressions for coupled acoustic-elastic media systems remain absent, despite their importance for analysing cross-correlation wavefields from [...]
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 [...]