Preprints
Filtering by Subject: Geophysics and Seismology
A Reproducible Framework for the Compressibility of Truncated Spherical-harmonic Planetary Potential-field Models
Published: 2026-07-09
Subjects: Geophysics and Seismology, Numerical Analysis and Computation, Numerical Analysis and Scientific Computing, Planetary Geophysics and Seismology
For a planetary potential field whose degree-variance spectrum decays as a convergent power law σ²_ℓ ∼ ℓ^−α (α > 1), a single measured exponent simultaneously fixes three classically distinct rates: the truncation-error decay rate, the Sobolev smoothness index, and the Kolmogorov n-width rate. Spherical-harmonic degree truncation is the standard yet inherently lossy way to compress such [...]
The Rise of Diamond Open Access Journals in Earth Sciences: Past Developments, Present Tensions, and Future Pathways
Published: 2026-07-08
Subjects: Biogeochemistry, Cosmochemistry, Earth Sciences, Geochemistry, Geology, Geomorphology, Geophysics and Seismology, Library and Information Science, Paleontology, Planetary Sciences, Sedimentology, Tectonics and Structure, Volcanology
Over roughly the last decade, a visible, community-led Diamond Open Access (OA) ecosystem has emerged in the Earth sciences, not as a departure from tradition, but as the latest expression of a long-standing culture of open, society-supported scholarly communication. While free-to-read, fee-free publishing initiatives have deep roots in the field, predating the Diamond terminology by decades and [...]
Leakage-audited machine learning versus ETAS for earthquake forecasting in the Sea of Marmara
Published: 2026-07-06
Subjects: Geophysics and Seismology, Physical Sciences and Mathematics
The Sea of Marmara hosts a seismic gap directly beneath a metropolitan region of some 18 million people, and the 23 April 2025 Mw 6.2 Kumburgaz earthquake renewed attention on whether short-term forecasting can add value there. We report a leakage-audited forecasting experiment built on a strictly causal, homogenized KOERI catalogue (31,329 model-box events, 2003–2026). Motivated by the finding [...]
When does array moveout help borehole phase picking? A leave-one-site-out, confound-free benchmark of array versus per-trace deep learning
Published: 2026-07-06
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Deep-learning phase pickers are increasingly deployed on borehole microseismic arrays, yet two questions central to operational monitoring remain poorly quantified: how well such models generalize to a site they were not trained on, and whether the cross-station moveout that an array provides actually improves that generalization. We give the first confound-free answer using the AMBER benchmark [...]
A hidden component of magnetic storms makes Earth's mantle transition zone look drier than it is
Published: 2026-07-04
Subjects: Geophysics and Seismology
Electromagnetic sounding provides a primary geophysical constraint on water in Earth's mantle transition zone, yet conductivity models disagree by up to an order of magnitude. We identify a source-side systematic invisible to internal consistency checks: omitting the degree-3 zonal (P₃⁰) storm-field component biases transition-zone conductivity by 0.1–0.35 decades, a tenth to a quarter of that [...]
ARGUS: A 17-ms End-to-End Deep Learning Pipeline for Real-Time Seismic Source Characterization and Ground Motion Prediction in Sparse-Network EGS/CCS Environments
Published: 2026-06-30
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We present ARGUS (Automated Real-time Geophysical Understanding System), an end-to-end deep-learning pipeline that jointly estimates hypocenter location, centroid moment tensor (CMT), and peak ground acceleration (PGA) distribution from sparse seismic networks, targeting induced-seismicity monitoring in enhanced geothermal systems (EGS) and carbon capture and storage (CCS). From as few as four to [...]
Denoising teleseismic data for deep Earth studies using a supervised deep-learning auto-encoder: a case study of diffracted waves from ULVZs
Published: 2026-06-27
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Seismic noise, particularly the microseism generated by the oceans, is a fundamental limitation on using short period (1 - 10 s) teleseismic data to study the deep Earth. Deep learning auto-encoders have proven effective at denoising seismic data in other applications. Here, we provide a demonstration of their potential for improving the quality of deep Earth seismic data, using Sdiff [...]
Earthquakes Source Scaling at Subfault Scales
Published: 2026-06-23
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Establishing scaling laws for large earthquakes remains challenging due to the heterogeneity of methodologies and datasets used to produce finite-fault models. In this study, we analyze source properties for 264 earthquakes using the NEIC finite-fault database, expanding previous efforts by examining rupture behavior over a broader magnitude range and capturing both established scaling trends and [...]
Tectonic pump closes the evolutionary loop for long-buried subseafloor microbes
Published: 2026-06-22
Subjects: Biogeochemistry, Geophysics and Seismology, Hydrology, Tectonics and Structure
Deep marine sediments host one of Earth’s largest microbial biospheres, yet most cells in this environment persist in a non-growing state for thousands to millions of years beneath kilometers of sediment. For natural selection to favor such extraordinary long-term survival, a mechanism must exist that is capable of returning buried living populations to near-surface environments, where [...]
When is curvature-level geoid validation feasible? A detectability-and-identifiability design rule, demonstrated on GSVS17
Published: 2026-06-22
Subjects: Geophysics and Seismology
Geoid-model validation campaigns compare observed geoid heights and slopes against models. This work asks what it takes to extend that comparison by one differential order — to curvature, the local change of slope — and gives a predictive design rule for when such a test is worthwhile. The rule rests on the classical fact that plumb-line curvature is a projection of the gravity Hessian, or [...]
Global Gravitational-Resonant Waves in the Arctic Basin: Visualizing Hidden Ocean Macrodynamics using 22-Year Passive Microwave Radiometry Data
Published: 2026-06-20
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Hydrology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology
The dynamics of the Arctic Ocean's sea ice cover are traditionally viewed through the lens of atmospheric forcing, ocean currents, and thermodynamic processes. In this paper, we propose a fundamentally new paradigm: the sea ice cover acts not as an elastic membrane transmitting mechanical stress, but as a passive two-dimensional indicator (analogous to Chladni figures) that visualizes a [...]
Linking double seismic zones to oceanic lithosphere rheological layering: the role of mid-lithospheric discontinuities
Published: 2026-06-18
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics
The origin of the ubiquitous lower seismic layer (LSL) in double seismic zones (DSZs) within subducting oceanic lithosphere remains one of the most persistent unresolved problems in subduction-zone seismicity. Analysis of recent geophysical observations reveals a close spatial association between the LSL and the oceanic mid-lithospheric discontinuity (MLD), a feature attributed to the [...]
HPHT Micro-to-Nano Seismic Comparison of GEIOS Nitrogen Hybrid Gas Nanofoam vs. Water-Proppant EGS
Published: 2026-06-18
Subjects: Geophysics and Seismology
Statement of peer-review status: This is a non-peer-reviewed preprint. The work derives from internal laboratory testing at Nanogeios Laboratory and has not been submitted to a peer-reviewed journal. For patent and intellectual-property security, certain sources and proprietary technical details (e.g., exact nanoparticle composition and surfactant/stabiliser chemistry) are intentionally not [...]
Effects of loading schemes in volumetric simulations of sequences of earthquakes and aseismic slip (SEAS) in subduction zones
Published: 2026-06-09
Subjects: Earth Sciences, Geophysics and Seismology, Tectonics and Structure
State-of-the-art simulations of sequences of earthquakes and aseismic slip (SEAS) require realistic loading conditions and physics-based constitutive laws to produce the full spectrum of fault slip. Previous studies have shown that loading schemes may affect long-term system behavior, including earthquake recurrence intervals. However, the effects of loading schemes on rupture characteristics and [...]
Gravity–topography regression across Antarctica: implications for isostatic regimes and subglacial crustal structure
Published: 2026-06-03
Subjects: Geophysics and Seismology
We investigate the relationship between Bouguer disturbance and equivalent topography across Antarctica using satellite gravity data, under the assumption that a linear relationship is expected at long wavelengths for Airy-type isostatic compensation. Equivalent topography ensures consistency across continental, marine, and ice-covered domains by expressing bathymetry and ice loads as [...]