Preprints
Filtering by Subject: Physical Sciences and Mathematics
Comparative Evaluation of Threshold Pressure Measurement Techniques in Faulted and Shale Formations
Published: 2025-11-16
Subjects: Physical Sciences and Mathematics
Reliable estimation of capillary threshold pressure is essential for evaluating the sealing capacity of subsurface flow barriers, which has important applications in fluid storage. This study compares the results of capillary threshold pressure measurements obtained from four experimental techniques: (i) gas breakthrough, (ii) mercury injection capillary pressure (MICP), (iii) Porosimetry under [...]
Standing wave-induced tidal shear in a submarine canyon in the Rockall Trough
Published: 2025-11-15
Subjects: Physical Sciences and Mathematics
Mixing in the ocean abyss sustains the deepest branches of the global overturning circulation, yet the processes that drive deep-ocean mixing remain poorly understood. Recent field measurements in a deep submarine canyon of the Rockall Trough have revealed that intense mixing occurs during strong, vertical shear-generated overturns exceeding 200 meters. These overturning events last only a few [...]
Temperature insensitive viscous deformation limits megathrust seismogenesis
Published: 2025-11-15
Subjects: Earth Sciences, Physical Sciences and Mathematics, Physics
Three models have been proposed to explain the downdip limit of the subduction seismogenic zone. The first is a temperature-controlled transition in rate-and-state frictional properties between 350–510°C, which inhibits earthquake nucleation. The second places the limit at the frictional and viscous failure envelope intersection. The third combines thermal and lithological controls, where 'warm' [...]
Palynofacies And Paleoenvironmental Studies of TDA-1 Well, Niger Delta Basin, Nigeria
Published: 2025-11-14
Subjects: Earth Sciences, Physical Sciences and Mathematics
The palynofacies and paleoenvironmental study of TDA-1 well, Niger Delta Basin, Nigeria between intervals of 6160 to 14470 feet (1878 to 4410 meter). The Niger Delta Basin is a crucial geological formation that has significant hydrocarbon reserves and supports diverse ecosystems where three main formations in ascending order are formed including the Paleocene Akata Formation, Eocene Agbada [...]
Unusual Drilling-Induced Stress Features - What To Do With You?
Published: 2025-11-14
Subjects: Physical Sciences and Mathematics
Drilling-induced features identified from borehole image logs provide direct constraints on in-situ stress orientations and magnitudes. Classic features such as drilling-induced tensile fractures and borehole breakouts have been extensively documented since the 1980s, predominantly in sedimentary rocks within hydrocarbon reservoirs. More recently, petal-centreline fractures have also been [...]
Developing an Open-access Telegram Bot for Automated, estimation and IA-based interpreted of OpenQuake Ground-Motion intensity measures
Published: 2025-11-13
Subjects: Education, Engineering, Life Sciences, Physical Sciences and Mathematics
The prediction of Intensity Measures (IMs) using Ground-Motion Models (GMMs) is a fundamental component of seismic hazard assessment. However, the best estimation of IMs traditionally requires specialised searchers, programming expertise, and the manual sourcing of regression coefficients. This complexity creates a significant barrier to rapid, scenario-based analysis for engineers, researchers, [...]
Rheological control on earthquake source kinematics and dynamics at the Hengill geothermal field
Published: 2025-11-07
Subjects: Physical Sciences and Mathematics
We analyze seismic source parameters of the induced earthquakes at the Hengill (Iceland) between 2018 and 202 to investigate rupture processes in a complex volcanic–geothermal setting. Our analysis reveals a source scaling relation that deviates from the commonly assumed M0 ∝ fc^-3. By combining stress tensor orientation, lithostatic and hydrostatic pressure, and frictional strength estimates, we [...]
Thoughts on prognostically modeling an eddying double-gyre ensemble mean
Published: 2025-11-06
Subjects: Physical Sciences and Mathematics
We address the question of separating the ocean’s deterministic response to time-dependent forcing from its intrinsic chaotic variability. Because the forcing is neither stationary nor periodic and spatial homogeneity is precluded by both the forcing pattern and boundary conditions, statistical analysis must rely on ensemble averaging. Here, we define this as the arithmetic mean over realizations [...]
Biases due to widespread use of low-cost sensors for urban heat stress assessments
Published: 2025-11-06
Subjects: Physical Sciences and Mathematics
Urban heat stress is an area of critical research interest due to its relevance for public health and policy. Given the lack of operational-grade weather stations within cities, different types of low-cost sensors have been used to assess urban heat stress. However, these sensors are traditionally not designed for capturing fine scale differences in temperature and humidity (i.e., the main [...]
Modelling the transport and dispersion of volcanic co-PDC ash clouds using NAME: an evaluation of source geometry and mass eruption rate
Published: 2025-11-03
Subjects: Earth Sciences, Physical Sciences and Mathematics, Volcanology
Pyroclastic density currents (PDCs) are gravity currents that frequently form during explosive volcanic eruptions. These ground-hugging density currents consist of high-temperature mixtures of pyroclasts (e.g., ash, pumice), lithics, and gas. They have the potential to generate co-PDC plumes, which detach from the underlying PDC as they buoyantly rise into the atmosphere. Co-PDC plumes, composed [...]
Homogenization of Elastic Wave Equation using Renormalization Group Theory
Published: 2025-11-03
Subjects: Physical Sciences and Mathematics
Seismic waves traveling through the Earth interact with heterogeneities of all scales along their path. Generally, we are interested in travel time associated with coarse-scale structures; however, fine-scale structures also influence the amplitude and travel time for all phases. The distribution of fine-scale heterogeneities not only affects travel times but also impacts how we observe [...]
DeepSubDAS: An Earthquake Phase Picker from Submarine Distributed Acoustic Sensing Data
Published: 2025-10-29
Subjects: Physical Sciences and Mathematics
Given the scarcity of seismometers in marine environments, traditional seismology has limited effectiveness in oceanic regions. Submarine Distributed Acoustic Sensing (DAS) systems offer a promising alternative for seismic monitoring in these areas. However, the existing machine learning model trained on land-based DAS data does not perform well with submarine DAS due to differences in noise [...]
Bimodal Astroclimatic Modulation of ENSO Dynamics by Net Shortwave Solar Radiation
Published: 2025-10-27
Subjects: Physical Sciences and Mathematics
The persistent Spring Predictability Barrier (SPB) suggests that current ENSO models may omit a crucial external forcing. This study identifies and quantifies a bimodal, season-dependent modulation of the El Niño–Southern Oscillation (ENSO) during the 1999–2024 period, driven by variations in net short-wave solar radiation. Using a SARIMAX framework combined with permutation tests, two distinct [...]
Emerging Remote Sensing Tools for Comprehensive Cryosphere Assessment
Published: 2025-10-27
Subjects: Climate, Earth Sciences, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Physical Sciences and Mathematics, Physical Sciences and Mathematics
This review synthesizes current remote sensing (RS) applications for monitoring Earth's cryosphere, encompassing ice sheets, glaciers, sea ice, snow cover, permafrost, and mountain ice features. It examines how satellite-based technologies, including radar interferometry, laser altimetry, passive microwave sensors, and optical imagery, have revolutionized cryospheric science by enabling [...]
Mars' Lowest and Highest Points Revisited
Published: 2025-10-25
Subjects: Physical Sciences and Mathematics, Planetary Geomorphology, Planetary Sciences
We present revised values for Mars’ extreme elevations using a blended digital elevation model (DEM) that combines altimetry collected from the Mars Orbiter Laser Altimeter (MOLA) on NASA’s Mars Global Surveyor with stereo imagery from the High Resolution Stereo Camera (HRSC) on ESA’s Mars Express. The widely cited minimum elevation is derived from an earlier MOLA-only DEM which lacks direct [...]