Preprints
Filtering by Subject: Geophysics and Seismology
Anomaly detection of Synthetic Aperture Radar Interferograms with semi-supervised machine learning
Published: 2025-10-31
Subjects: Geophysics and Seismology, Volcanology
The aim of this research is to detect Earth's deformation from Interferometric Synthetic Aperture Radar (InSAR) images through a semi-supervised machine learning algorithm called Least-Squares Two-sample Test (LSTT). This algorithm computes the probability distributions of two samples to assess if they belong to the same probability distribution. At the same time, it gives the divergence of these [...]
Intermittent supershear rupture punctuated by barrier-induced stopping phase during the 2025 Mw 7.8 Myanmar Earthquake: Evidence from near-fault strong motion observation
Published: 2025-10-24
Subjects: Geology, Geophysics and Seismology, Physical Sciences and Mathematics
Supershear rupture has been investigated by many studies, yet its exact characteristics during natural earthquakes are not fully clear, due to the paucity of near-field constraints. Here we analyze the strong motion data recorded at a near-fault station during the 2025 Mw 7.8 Myanmar earthquake to estimate the detailed source process around that station. By comparing simulated velocity waveforms [...]
Global presence and absence of ultra-low velocity zones as seen by Sdiff postcursors
Published: 2025-10-24
Subjects: Earth Sciences, Geophysics and Seismology
The core-mantle boundary is a region of significant lateral heterogeneity. Two antipodal large low-velocity provinces (LLVPs) dominate the lower mantle, while smaller but more extreme ultra-low velocity zones (ULVZs) pepper the lowermost mantle in a variety of morphologies. These ULVZs have been linked to both the edges of LLVPs and to plume-related hotspots, the latter of which may plausibly be [...]
The Effects of Fluid Pre-Conditioning on the Deformational Response of a Laboratory Fault
Published: 2025-10-16
Subjects: Geophysics and Seismology, Hydrology
Surface Wave Dispersion Calculation and Sensitivity Analysis in Anisotropic and Weakly Attenuating Medium Based on Spectral Element Method
Published: 2025-10-15
Subjects: Geophysics and Seismology
We present a comprehensive and flexible framework for modeling 1-D surface wave dispersion in anisotropic and weakly attenuating media. The spectral element method is employed to accommodate various stress-strain relationships, boundary conditions, and multiphysics coupling effects. Both radial and general complex anisotropic relations can be incorporated. Standard linear solid models, along with [...]
Glacier processes from seismic recordings on Sørsdal Glacier, East Antarctica
Published: 2025-10-15
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Physical Sciences and Mathematics
A catalogue of seismic events is produced and analysed for Sørsdal Glacier, East Antarctica. Recordings were made using an irregular array of three broadband and eight short-period seismometers, with approximately 3 km aperture, deployed slightly upstream of the expected grounding line during the 2017-18 austral summer. The broadband sensors were used to construct the event catalogue, and the [...]
Seismicity Migration from Fluid Injection: Laboratory Experiments and Numerical Models Illuminate Volume-Driven versus Pressure-Diffusion-Driven Migration
Published: 2025-10-10
Subjects: Geophysics and Seismology, Geotechnical Engineering, Mining Engineering
Fluid injection into the subsurface can induce seismicity by reactivating shear rupture, which typically produces larger earthquake magnitudes than tensile rupture. In laboratory shear rupture experiments, pressurization of the entire fault is often limited because large unconfined samples allow fluid to leak at free surfaces. In this study, we investigated shear fault reactivation by directly [...]
Constraining On- and Off-Fault Nonlinear Dynamic Rupture Parameters via Hierarchical Bayesian Inversion for the 2019 Mw 7.1 Ridgecrest Earthquake
Published: 2025-09-20
Subjects: Geophysics and Seismology
We present the first multilevel Bayesian inversion to quantify uncertainties and correlations among on- and off-fault dynamic rupture parameters for the 2019 Mw 7.1 Ridgecrest earthquake. The inversion is constrained by multidisciplinary surface deformation data, including fault-parallel offsets from satellite imagery, high-rate GNSS time series, and static GNSS displacements, and is enabled by [...]
Efficient Self-Attention Based Joint Optimization for Lithology and Petrophysical Parameter Estimation in the Athabasca Oil Sands
Published: 2025-09-17
Subjects: Artificial Intelligence and Robotics, Earth Sciences, Geology, Geophysics and Seismology
Accurately identifying lithology and petrophysical parameters, such as porosity and water saturation, are essential in reservoir characterization. Manual interpretation of well-log data, the conventional approach, is not only labor-intensive but also susceptible to human errors. To address these challenges of lithology identification and petrophysical parameter estimation in the Athabasca Oil [...]
Massive High-Fidelity Focal Mechanisms Reveal Detailed Structure of Re-Activated Faults During Hydraulic Fracturing in Western Canada
Published: 2025-09-14
Subjects: Geophysics and Seismology
Microseismic focal mechanism solutions (FMSs) are essential for understanding reservoir stress changes and rock fracturing during hydraulic fracturing. While machine learning has shown strong performance in seismic data processing tasks, including phase picking and magnitude estimation, as well as identifying P-wave first-motion polarity for moderate to large earthquakes to invert FMSs, its [...]
Shear-wave splitting measured for permanent reservoir monitoring systems: an example from the Snorre field
Published: 2025-09-06
Subjects: Geophysics and Seismology
Microseismic monitoring of offshore CO2 storage projects is likely to include some deployment of offshore sensors. To improve the value proposition of this monitoring infrastructure, it is important to consider what other information can be gained about the CO2 storage complex and the surrounding region. Shear-wave splitting is one potential source of added value to microseismic monitoring of CO2 [...]
Passive Monitoring of in situ Stress Using Shear-Wave Splitting: Applications to CO2 Storage and Beyond
Published: 2025-09-05
Subjects: Geophysics and Seismology
Characterising the in situ stress field is important for a range of industrial applications, such as geological CO₂ storage, geothermal projects, hydrocarbon extraction, geological disposal facilities, and for natural seismic hazard assessment. Shear-wave splitting is a passive measurement which can be used to passively monitor changes in the in situ stress field. We combine borehole stress and [...]
3D surface displacement estimation over the Groningen gas field, the Netherlands
Published: 2025-08-29
Subjects: Earth Sciences, Environmental Monitoring, Geophysics and Seismology, Mining Engineering, Oil, Gas, and Energy
Since 1964, the Groningen gas field in the Netherlands has experienced significant subsidence due to gas extraction. Although InSAR has been widely used to estimate the vertical displacements of the field, capturing the full three-dimensional deformation, including omnidirectional horizontal components, remained a challenge and has only been achieved from spatially sparse GNSS observations. The [...]
Using ruptures from an earthquake cycle simulator to test geodetic early warning system performance
Published: 2025-08-29
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
New Zealand's vulnerability to seismic hazards highlights the need for systems capable of providing earthquake early warning (EEW) or rapid notice of strong shaking. Large offshore earthquakes along the subduction zone east of the North Island could also trigger catastrophic tsunamis, inundating coastal communities in under an hour. While New Zealand operates a robust seismic and geodetic network [...]
Assessing inversion uncertainty from initial model variability: A practical approach for geothermal MT exploration
Published: 2025-08-19
Subjects: Computational Engineering, Geophysics and Seismology, Geotechnical Engineering, Numerical Analysis and Scientific Computing, Power and Energy
We propose a simple and computationally efficient approach to evaluate the uncertainty in magnetotelluric (MT) inversion results arising from differences in initial models. Spatially smooth initial resistivity structures are generated by assigning random resistivity values to fixed representative points and applying Kriging-based interpolation. A series of 3D inversions was conducted using these [...]