Preprints
Filtering by Subject: Physical Sciences and Mathematics
Continental-Scale Carbonate Sedimentation and Environmental Correlates of the Shuram-Wonoka Excursion
Published: 2025-07-01
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Geology, Paleontology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Strata of the Ediacaran Period record many Earth-Life features that distinguish the Neoproterozoic-Phanerozoic transition. However, it is difficult to determine cause and effect relationships between Ediacaran events. Continental-scale patterns of sedimentation have been used as proxies to investigate controls on Phanerozoic macroevolution, including sea level drivers and potential carbon cycling [...]
Determination of REE abundances and Eu isotope ratio in GSJ and NIST feldspar reference standards (JF-1, JF-2, SRM 70a, 70b and SRM 99a) using ICP-QMS and MC-ICP-MS
Published: 2025-07-01
Subjects: Physical Sciences and Mathematics
Rare earth element (REE) concentrations in feldspars provide valuable information for understanding geochemical implications during the evolution of igneous rocks due to magma differentiation. Europium (Eu) is one of the REEs and exists in oxidation states (Eu2+ and Eu3+) states. Eu2+ can be substituted for Ca2+ during plagioclase feldspar crystallization in reducing magmas, which becomes a cause [...]
Field evidence for non-linear IP effects in a volcanic hydrothermal system using reciprocal data.
Published: 2025-06-27
Subjects: Earth Sciences, Physical Sciences and Mathematics, Volcanology
In electrical geophysical methods it is often assumed that the resistivity or chargeability, behaves linearly with the applied electrical current. However, non-linearity has been reported in Induced Polarization (IP) and can be caused by oxidation-reduction reactions or reactions at the surface of clay minerals. Methods to determine the presence of non-linear effects exist and involve analysis of [...]
Mapping upper mantle discontinuities beneath the Australian continent using multimode surface waves and receiver functions
Published: 2025-06-27
Subjects: Earth Sciences, Physical Sciences and Mathematics
Spatial distributions of upper mantle discontinuities beneath the Australian continent are mapped using a large number of station-based 1-D S-velocity profiles with radial anisotropy, derived from joint Bayesian inversions of multimode surface waves and P-wave receiver functions. Numerous permanent and temporary stations across Australia enable us to constrain localized seismic velocity [...]
An explainable machine learning prediction system for early-warning of heat stress on Florida’s Coral Reef
Published: 2025-06-25
Subjects: Earth Sciences, Environmental Sciences, Marine Biology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Coral reefs are facing increasing threats from rising ocean temperatures, necessitating timely and localized prediction tools to inform reef management and conservation. This study introduces a machine learning framework capable of forecasting the onset of moderate coral heat stress at site-specific resolution on Florida’s Coral Reef. Leveraging the XGBoost algorithm, the data-driven prediction [...]
A SEISMIC MOMENT MAGNITUDE SCALE
Published: 2025-06-24
Subjects: Engineering, Physical Sciences and Mathematics
Theaimofobtaininga single scale for earthquake magnitudes has led many studies in the past to either develop relationships among various existing scales or develop an altogether new scale to represent a wide range of magnitudes on a single scale. Although a reliable and standardized estimation of earthquake size is a basic requirement for all tectonophysical and engineering applications, [...]
Fibre-optic exploration of the cryosphere
Published: 2025-06-23
Subjects: Physical Sciences and Mathematics
The icy parts of the Earth, known as the cryosphere, are an integral part of the climate system. Comprehensively understanding the cryosphere, requires dense observations, not only of its surface, but also of its internal structure and dynamics. Seismic methods play a central role in this endeavour. Fibre-optic sensing is emerging as valuable complement and alternative to well-established [...]
New methods for predicting the start and other features of the UK (Northern Hemisphere) Sporadic E (Es) radio propagation season
Published: 2025-06-22
Subjects: Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The sporadic E mode of propagation is briefly described and reviewed. The question is posed could we ever predict the start and duration of the main propagation season. A new hypothesis is proposed based on the modulation of planetary weather and wave circulations and their effect on the Es
Changes in stratiform heating structure due to surface warming weaken and accelerate convectively coupled Kelvin waves
Published: 2025-06-20
Subjects: Physical Sciences and Mathematics
Although stratiform heating plays a crucial role in tropical convective systems, we do not fully understand (1) how stratiform heating would change in response to surface warming and (2) how those changes would affect convectively-coupled equatorial waves. This study analyzes the changes in stratiform heating structure and convectively-coupled Kelvin waves (KWs) associated with surface warming [...]
Maintenance of convectively coupled Kelvin waves: relative importance of internal thermodynamic feedback and external momentum forcing
Published: 2025-06-20
Subjects: Physical Sciences and Mathematics
Previous studies suggest that convectively coupled Kelvin waves (KWs) are likely maintained by two distinct processes: (1) the internal thermodynamic feedback between KW diabatic heating and temperature and (2) the external momentum forcing from the midlatitude Rossby waves exerting on KW zonal wind. This study quantifies the relative importance of the two processes on KW maintenance by comparing [...]
Topographic evidence for recent intraplate reactivation in NW Uruguay
Published: 2025-06-20
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics, Tectonics and Structure
Located in eastern South America, Uruguay has been considered tectonically inactive since rifting in the Late Cretaceous. Here, we use a high-resolution digital elevation model (DEM) and field observations to investigate the presence of recent tectonic activity in the Basaltic Plateau, northwest Uruguay. Based on topographic-, drainage network- and field-based data, we identify evidence for [...]
The Stotfield silcrete (or ‘Stotfield Cherty Rock’), Moray, eastern Scotland: Characterization and discussion of an archaeologically important lithic raw material
Published: 2025-06-18
Subjects: Earth Sciences, Human Geography, Physical Sciences and Mathematics, Social and Behavioral Sciences
We describe and discuss a lithic raw material new to Scottish prehistoric research: the Stotfield silcrete or Stotfield Cherty Rock. This material was well-known to Scottish geologists, but it was only recently realized that it had been used by prehistoric people in Moray, eastern Scotland. We describe our examination of archaeological Stotfield silcrete, as well as field information relating to [...]
Predictability and randomization of surface air temperature chaotic dynamics
Published: 2025-06-18
Subjects: Physical Sciences and Mathematics
The surface air temperature daily records at the land-based locations with different climate conditions (from the Arctic to Patagonia) have been studied on the daily to intraseasonal time scales (low-frequency annual and seasonal variations have been removed by subtracting a wavelet regression from the daily records). It is shown that the power spectra of the daily time series exhibit a universal [...]
The 1993 Jerzmanowice event in Poland and the 1908 Tunguska event
Published: 2025-06-17
Subjects: Education, Physical Sciences and Mathematics
This paper is a continuation of a series of works, devoted to various aspects of the 1908 Tunguska event. In this paper its author would like to draw attention to the phenomenon that is sometimes called the Polish Tunguska in the Polish media, although it would probably be more correct to call it mini-Tunguska. In the evening of January 14, 1993, the village Jerzmanowice (about 20 km NW from [...]
Development and Performance Evaluation of a WT-LSTM Hybrid Model for Global Land Meteorological Drought Prediction
Published: 2025-06-17
Subjects: Engineering, Physical Sciences and Mathematics
In recent years, droughts have become increasingly frequent worldwide, leading to issues such as reduced agricultural yields and ecological degradation in various regions. To mitigate the impact of drought on human survival and development, this study utilizes the Standardized Precipitation Evapotranspiration Index (SPEI) to analyze the spatiotemporal variations of global droughts. The results [...]