Preprints
Filtering by Subject: Earth Sciences
Different mechanisms of Arctic first-year sea-ice ridge consolidation observed during the MOSAiC expedition
Published: 2023-05-10
Subjects: Earth Sciences, Glaciology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Sea-ice ridges constitute a large fraction of the ice volume in the Arctic Ocean, yet we know little about the evolution of these ice masses. Here we examine the thermal and morphological evolution of an Arctic first-year sea-ice ridge, from its formation to advanced melt. Initially the mean keel depth was 5.6 m and mean sail height was 0.7 m. The initial rubble macroporosity (fraction of [...]
Environmental controls on the brGDGT and brGMGT distributions across the Seine River basin (NW France): Implications for bacterial tetraethers as a proxy for riverine runoff
Published: 2023-05-07
Subjects: Biogeochemistry, Earth Sciences, Environmental Sciences
Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are bacterial lipids that have been largely used as environmental proxies in continental paleorecords. Another group of related lipids, branched glycerol monoalkyl glycerol tetraethers (brGMGTs), has recently been proposed as a potential paleotemperature proxy. Nevertheless, the sources and environmental dependencies of both brGDGTs and [...]
Slip-stuck kinematics of fault surfaces in laboratory experiments: implications for heterogeneous slip distributions during earthquake events
Published: 2023-05-05
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Combining field observations with analogue laboratory experiments, this study aims to use surface-roughness characteristics as an indicator of the heterogeneous slip partitioning along shear surfaces. We investigated the roughness of shear surfaces in sheared quartzite of the Singhbhum Shear Zone, eastern India, and identified two distinct kinematic domains: slip zone and stuck zone, marked by [...]
Tracing isotope precipitation patterns across Mexico
Published: 2023-05-04
Subjects: Earth Sciences, Environmental Sciences
Mexico encompasses a large spectrum of landscapes with topographic, geographic, and climatic factors interacting in a complex ecohydrological setting. For decades, isotope hydrogeological tools have been applied in Mexico using short-term or seasonal local meteoric water lines as valid input functions. Yet, a systematic evaluation of meteoric isotope characteristics is still lacking. Here we [...]
Geophysical and Geochemical Constraints on Magma Storage Depths along the Cascade Arc: Knowns and Unknowns
Published: 2023-05-03
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Volcanology
The iconic volcanoes of the Cascade arc stretch from Lassen Volcanic Center in northern California, through Oregon and Washington, to the Garibaldi Volcanic Belt in British Columbia. Recent studies have reviewed differences in the distribution and eruptive volumes of vents, as well as variations in geochemical compositions and heat flux along strike (amongst other characteristics). We investigate [...]
Soil pore water evaporation and temperature influences on clay mineral paleothermometry
Published: 2023-05-02
Subjects: Earth Sciences, Physical Sciences and Mathematics
Clay mineral isotope paleothermometry is fundamental to understanding Earth's climate system and landscape evolution. Status quo methods, however, assume constant factors, such as temperature and water isotopic compositions, and ignore seasonality, soil water evaporation and depth dependent temperature changes. We propose first-order modifications to address these factors and test them in a [...]
Linear analysis of ice-shelf topography response to basal melting and freezing
Published: 2023-04-28
Subjects: Applied Mathematics, Dynamic Systems, Earth Sciences, Fluid Dynamics, Glaciology, Physical Sciences and Mathematics, Physics
Floating ice shelves in Antarctica and Greenland limit land-ice contributions to sea level rise by resisting the flow of grounded ice. Melting at the surface and base of ice shelves can lead to destabilisation by promoting thinning and fracturing. Basal melting often results in channelised features that manifest as surface topography due to buoyancy. The assumption of hydrostatic flotation [...]
Reconstructing subglacial lake activity with an altimetry-based inverse method
Published: 2023-04-28
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Subglacial lake water-volume changes produce ice-elevation anomalies that provide clues about water flow beneath glaciers and ice sheets. Significant challenges remain in the quantitative interpretation of these elevation-change anomalies because the surface expression of subglacial lake activity depends on basal conditions, rate of water-volume change, and ice rheology. To address these [...]
Earth tides can reactivate shallow faults and trigger seabed methane emissions
Published: 2023-04-26
Subjects: Earth Sciences
The role of solid Earth tide in fault reactivation has significant implications for understanding earthquake triggering, carbon sequestration, and the global carbon budget. Despite extensive research on this topic over the years, the relationship between Earth tide and fault reactivation remains unclear. In this study, we investigate the potential influence of solid Earth tide on the reactivation [...]
The Dynamics of the India-Eurasia Collision: Faulted Viscous Continuum Models Constrained by High-Resolution Sentinel-1 InSAR and GNSS Velocities
Published: 2023-04-22
Subjects: Earth Sciences
The dynamics of lithospheric deformation in the India-Eurasia collision zone has been debated over many decades. Here we test a two-dimensional (2-D) Thin Viscous Shell (TVS) approach that has been adapted to explicitly account for displacement on major faults and investigate the impact of lateral variations in depth-averaged lithospheric strength. We present a suite of dynamic models to explain [...]
A key role for diffusion creep in eclogites: Omphacite deformation in the Zermatt-Saas Unit, Italian Alps
Published: 2023-04-18
Subjects: Earth Sciences, Geochemistry, Geology, Mineral Physics, Tectonics and Structure
Eclogites are important components of subduction-collision zones, with the mineral omphacite acting as the supporting framework mineral that accommodates the majority of any accumulated strain. As such it is important to determine which deformation mechanisms operate in omphacite during and after its formation to understand the rheology of deforming subducted crust. Such information is key to [...]
Calling for a National Model Benchmarking Facility
Published: 2023-04-14
Subjects: Biology, Computer Sciences, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Life Sciences, Oceanography and Atmospheric Sciences and Meteorology, Other Life Sciences, Physical and Environmental Geography, Physical Sciences and Mathematics, Planetary Sciences, Systems Biology
The modern world uses predictive computer models for many important purposes, including weather predictions, epidemic management, flood forecasting and warnings, and economic policymaking. We need to know how much we can trust the projections of these models, not only to achieve more accurate projections for systems, but also to undertake scientific learning about systems by incrementally testing [...]
Rifting a crustal mosaic – The influence of basement rheology and lithology on rift physiography in the Great South Basin, New Zealand
Published: 2023-04-13
Subjects: Earth Sciences, Geology, Tectonics and Structure
The make-up of continental crust reflects its past tectonic history, containing a multitude of different lithological units and pre-existing structures that vary in strength with crustal properties typically varying across short distances. These variations exist across a range of scales and exert a great control over multiple aspects of rift physiography, including rift structural style, fault [...]
SilicH2O: a graphical user interface for processing silicate glass Raman spectra and quantifying H2O
Published: 2023-04-13
Subjects: Earth Sciences, Geology, Volcanology
H2O contents of magmas strongly impact the explosivity of volcanic eruptions, as well as their rheological properties and crystallisation behaviour. Accurate analyses of H2O in magmatic liquids are therefore vital for our understanding of the dynamics of magmatic processes and eruptions. Raman spectroscopy provides an accessible, affordable and high spatial resolution technique for estimating H2O [...]
Consolidated Geothermal Database UK (CGD-UK): A digital open license database for temperature and thermal conductivity in the UK.
Published: 2023-04-08
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Natural Resource Economics, Oil, Gas, and Energy, Other Earth Sciences, Tectonics and Structure
Variations in subsurface heat flow within the upper crust control the distribution of geothermal resources. Development of a robust understanding of these variations requires reliable measurements of temperature and thermal conductivity. To date, measurements of temperature and conductivity onshore the UK have been unavailable in an accessible, clearly structured digital format. Here, we rectify [...]