Preprints
Filtering by Subject: Physical Sciences and Mathematics
An Enhanced Deep-Learning Catalog of the Mw 8.8 Maule Aftershock Sequence
Published: 2025-03-17
Subjects: Physical Sciences and Mathematics
We re-examine the aftershock sequence of the Mw 8.8 Maule earthquake in south-central Chile using deep learning on 10 months of continuous seismic data from 156 temporary stations along the rupture zone (March 2010–March 2011). By integrating back-projection and matched filtering with PhaseNet (a deep-learning phase picker), we initially identify 99,137 earthquakes. We then relocate these events [...]
Interactive annular mode links jet stream-ocean coupling to decadal Northern Hemispheric warmth
Published: 2025-03-17
Subjects: Physical Sciences and Mathematics
The atmospheric jet stream governs the distribution and intensity of midlatitude weather systems and climate variability. In the Northern Hemisphere, meridional migrations of the jet stream are directly linked to the frequency and magnitude of extreme weather events. While previous studies have established that jet stream fluctuations are modulated by spatio-temporal variations in diabatic [...]
Summertime sediment storage on the Alaskan Beaufort Shelf and implications for ice-sediment rafting and shelf erosion
Published: 2025-03-14
Subjects: Physical Sciences and Mathematics
Arctic coastlines are known to be rapidly eroding, but the fate of this material in the coastal ocean (and the sedimentary dynamics of Arctic continental shelves in general) is less well-constrained. This study used summertime mooring data from the Alaskan Beaufort Shelf to study sediment-transport patterns which are dominated by waves and wind-driven currents. Easterly wind events account for [...]
Thermogenic Methane Production in Antarctic Subglacial Hydrocarbon Seeps
Published: 2025-03-14
Subjects: Physical Sciences and Mathematics
Methane forms beneath ice sheets through microbial methanogenesis and thermogenic breakdown of organic matter, creating a potentially large greenhouse gas reservoir prone to release during glacial retreat. Subglacial thermogenic methanogenesis can increase gas buildup and create oases for life, but this process has not yet been observed in Antarctica, contributing to uncertainty in the spatial [...]
Hothouse hydrology: Evolving river dynamics in the Eocene Montllobat and Castissent Formations, Southern Pyrenees
Published: 2025-03-14
Subjects: Physical Sciences and Mathematics
Rivers are highly sensitive to climate and tectonic change, and understanding how fluvial systems respond to greenhouse climates in dynamic tectono-geomorphic settings is vital to projecting imminent landscape change in the face of global warming. We look to the southern Pyrenean Tremp-Graus basin during the Early Eocene Climatic Optimum (EECO), analogous to future anthropogenic climate [...]
Is abyssal dark oxygen production even possible at all?
Published: 2025-03-10
Subjects: Chemistry, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Physical principles need to be respected when interpreting controversial findings such as the production of abyssal oxygen. Such extraordinary claims must be analysed carefully before a large research effort is mounted and valuable human and financial resources are wasted based on flawed data. We are aware of the sensitivities around polymetallic nodules and their potential value as a source of [...]
Persistent high-pressure magma storage beneath a near-ridge ocean island volcano (Isla Floreana, Galápagos)
Published: 2025-03-09
Subjects: Physical Sciences and Mathematics
Volcanic evolution in ocean island settings is often controlled by variations in the chemistry and volumetric flux of magma from an underlying mantle plume. In locations such as Hawaiʻi or Réunion, this results in predictable variations in magma chemistry, the rate of volcanic activity, and the depth of magma storage with volcanic age and/or distance from the center of plume upwelling. These [...]
Fracturing during freezing in salty ice: preliminary analysis using a low-cost model system
Published: 2025-03-08
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
The fracture properties of saline water ice play an important role in governing the mechanical behavior of sea ice, marine ice sheets, and icy planetary bodies. Here, we design a low-cost experimental system based on a simple observation: fractures form when freshwater is frozen in a plastic bag, but do not form when a small amount of NaCl salt (several g/L) is added before freezing. We [...]
Improved LA-Q-ICP-MS U-Pb Zircon Age Estimates for Young (< 10 Ma) Zircons & Quantification of Bias in CL Guided Spot Selection
Published: 2025-03-07
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
We present a new approach to reducing U-Pb data from zircons obtained by laser ablation-quadrupole-inductively coupled plasma-mass spectrometry (LA-Q-ICP-MS), with emphasis on young (< 10 Ma) zircons. In young zircons the 207Pb yield is extremely low, generating a relatively high abundance of zero values during analyses. This impacts the use of 207Pb/206Pb in application of Tera-Wasserburg [...]
Detecting rapid lateral changes of upper mantle discontinuities using azimuth-dependent P-wave receiver functions and multimode surface waves
Published: 2025-03-06
Subjects: Physical Sciences and Mathematics
Lateral structural variations in the upper mantle generate azimuthal dependence in receiver functions (RFs) based on incoming directions of body waves. Although these azimuthal variations in RFs have not been considered in earlier studies of RF inversions, they provide a means to image localized changes in upper mantle interfaces. In this study, we incorporate azimuth-dependent RFs into a joint [...]
Velocity of climate change and the vulnerability of mountain lake landscapes
Published: 2025-03-05
Subjects: Life Sciences, Physical Sciences and Mathematics
Freshwater ecosystems in mountain landscapes are increasingly threatened by climate change. Accumulated heat in ecosystems can result in lethal short-term heat exposure, while the velocity of change governs severity and rates of long-term heat exposure. Here, we novelly integrate heat accumulation and velocity of change approaches to classify climate-vulnerable USA mountain lake watersheds. Our [...]
Generative Data Assimilation for Surface Ocean State Estimation from Multi-Modal Satellite Observations
Published: 2025-03-05
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Estimating the surface ocean state at mesoscale eddy-resolving scales is essential for understanding the role of eddies in climate and marine ecosystems. Satellites provide multi-modal observations through sea surface height, temperature (SST), and salinity (SSS). However, each variable is observed with varying resolutions and sparsity, while some variables, such as surface currents, are not yet [...]
Reduced Precipitation on Rapa Nui During the Decline of the Moai Culture
Published: 2025-03-04
Subjects: Atmospheric Sciences, Climate, Environmental Sciences, Environmental Studies, Geography, Human Geography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
From approximately 1200-1600 CE, Polynesian settlers on the island of Rapa Nui engaged in megalithic monument construction, crafting hundreds of Ahu platforms and Moai statues from volcanic bedrock. The decline of this tradition has intrigued archaeologists for decades. The most widely disseminated hypothesis surrounding the demise of the Ahu Moai culture suggests that the Rapanui overexploited [...]
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 [...]
Conduit dynamics of the Rungwe Pumice eruption (Tanzania): From storage to fragmentation of phonolitic-trachytic magmas
Published: 2025-03-04
Subjects: Physical Sciences and Mathematics
The eruptive style and explosivity of a rising magma are initially shaped by the conditions established in the magmatic plumbing system. However, processes in the conduit during ascent exert a large influence on the final eruption style. Peralkaline magmas—bearing an agpaitic index>1—typically have high water saturation levels, promoting explosive behaviour during ascent. At the same time, [...]