Preprints
Filtering by Subject: Physical Sciences and Mathematics
Estimating Ocean Surface Currents from Satellite Observable Quantities with Machine Learning
Published: 2021-03-03
Subjects: Physical Sciences and Mathematics
Global surface currents are usually inferred from directly observed quantities like sea-surface height, wind stress by applying diagnostic balance relations (like geostrophy and Ekman flow), which provide a good approximation of the dynamics of slow, large-scale currents at large scales and low Rossby numbers. However, newer generation satellite altimeters (like the upcoming SWOT mission) will [...]
Seasonal dispersal of fjord meltwaters as an important source of iron to coastal Antarctic phytoplankton
Published: 2021-03-03
Subjects: Physical Sciences and Mathematics
Glacial meltwater from the western Antarctic Ice Sheet is hypothesized to be an important source of cryospheric iron, fertilizing the Southern Ocean, yet its trace metal composition and factors which control its dispersal remain poorly constrained. Here we characterize meltwater iron sources in a heavily glaciated western Antarctic Peninsula (WAP) fjord. Using dissolved and particulate ratios of [...]
Research 339: High-resolution climate projections for Ireland. A multi-model ensemble approach
Published: 2021-03-02
Subjects: Physical Sciences and Mathematics
The method of regional climate modelling was employed to assess the impacts of a warming climate on the 21st-century climate of Ireland. The regional climate model (RCM) simulations were run at high spatial resolution (3.8 and 4 km), the first systematic study of its kind at this scale, thus allowing a better evaluation of the local effects of climate change. To address the issue of uncertainty, [...]
Extending full-plate tectonic models into deep time: Linking the Neoproterozoic and the Phanerozoic
Published: 2021-03-02
Subjects: Physical Sciences and Mathematics
Recent progress in plate tectonic reconstructions has seen models move beyond the classical idea of continental drift by attempting to reconstruct the full evolving configuration of tectonic plates and plate boundaries. A particular problem for the Neoproterozoic and Cambrian is that many existing interpretations of geological and palaeomagnetic data have remained disconnected from younger, [...]
Closure of the Proterozoic Mozambique Ocean was instigated by a late Tonian plate reorganization event
Published: 2021-03-02
Subjects: Physical Sciences and Mathematics
Plate reorganization events involve fundamental changes in lithospheric plate-motions and can influence the lithosphere-mantle system as well as both ocean and atmospheric circulation through bathymetric and topographic changes. Here, we compile published data to interpret the geological record of the Neoproterozoic Arabian-Nubian Shield and integrate this with a full-plate tectonic [...]
Birth of a large volcanic edifice offshore Mayotte via lithosphere-scale dike intrusion
Published: 2021-03-02
Subjects: Physical Sciences and Mathematics
Volcanic eruptions shape Earth’s surface and provide a window into deep Earth processes. How the primary asthenospheric melts form, pond and ascend through the lithosphere is, however, still poorly understood. Since 10 May 2018, magmatic activity has occurred offshore eastern Mayotte (North Mozambique channel), associated with large surface displacements, very-low-frequency earthquakes and [...]
Is there a Speed Limit for the Thermal Steady-State Assumption in Continental Rifts?
Published: 2021-03-01
Subjects: Earth Sciences, Physical Sciences and Mathematics
The lithosphere is often assumed to reside in a thermal steady-state when quantitatively describing the temperature distribution in continental interiors and sedimentary basins, but also at active plate boundaries. Here, we investigate the applicability limit of this assumption at slowly deforming continental rifts. To this aim, we assess the tectonic thermal imprint in numerical experiments that [...]
Temperature variability and extremes both affect economic growth
Published: 2021-02-26
Subjects: Environmental Sciences, Physical Sciences and Mathematics
Changes in temperature averages, variability, and extremes may all independently affect economic growth under climate change. Kotz et al. (2021) show that temperature variability reduces growth, but find no significant effect of temperature extremes. Recreating their results, here we show that temperature extremes do indeed affect growth independently from the effects of variability. Our results [...]
3D modeling of long-term slow slip events along the flat slab segment in the Guerrero Seismic Gap, Mexico
Published: 2021-02-26
Subjects: Physical Sciences and Mathematics
During the last two decades, quasi-periodic long-term slow-slip events (SSEs) of magnitudes up to Mw7.5 have been observed about every 4 years in the Guerrero Seismic Gap. Here we present numerical simulations of the long-term SSE cycles along the 3D slab geometry of central Mexico. Our model accounts for the hydrated oceanic crust in the framework of rate-and-state friction. The modeled SSE [...]
Reassessing Eastern Mediterranean tectonics and earthquake hazard from the AD 365 earthquake
Published: 2021-02-26
Subjects: Physical Sciences and Mathematics
The hallmark of great earthquakes (Mw ≈ 8.3-8.5) in the Mediterranean is the 21 July AD 365 earthquake and tsunami that destroyed cities and killed thousands of people throughout the Eastern Mediterranean. This event is intriguing because most Mediterranean subduction forearcs exhibit pervasive crustal extension and minimal definitive evidence exists for great subduction megathrust earthquakes, [...]
The Merluza Graben: how a failed spreading centre influenced margin structure, salt deposition and tectonics in the Santos Basin, Brazil
Published: 2021-02-26
Subjects: Physical Sciences and Mathematics
The relative timing between crustal extension and salt deposition can vary spatially along passive margin salt basins as continents unzip or as the locus of extension shifts towards the embryonic ocean spreading centre. Determining the relative timing of salt deposition, rifting, and seafloor spreading is often problematic due to the diachronous nature of rifting, the ability of salt to fill [...]
A Reduced Order Approach for Probabilistic Inversions of 3D Magnetotelluric Data II: Joint inversion of MT and Surface-Wave Data
Published: 2021-02-25
Subjects: Physical Sciences and Mathematics
Joint probabilistic inversions of magnetotelluric (MT) and seismic data has great potential for imaging the thermochemical structure of the lithosphere as well as mapping fluid/melt pathways and regions of mantle metasomatism. In this contribution we present a novel probabilistic (Bayesian) joint inversion scheme for 3D MT and surface-wave dispersion data particularly designed for large-scale [...]
Diversity, Equity, and Inclusion: tackling under-representation and recognition of talents in Geochemistry and Cosmochemistry
Published: 2021-02-25
Subjects: Physical Sciences and Mathematics, Social and Behavioral Sciences
Diversity, at every step along the scientific path, drives innovative research. Scientific societies, like the Geochemical Society (GS) and the European Association of Geochemistry (EAG), have a significant influence over which discoveries and innovators are celebrated. Such choices impact the future of research, and therefore influence the evolution of our discipline and its relationship to the [...]
Lithostratigraphy and chemostratigraphy of salt diapir sedimentary inclusions: unravelling Ediacaran salt–sediment interaction in the Flinders Ranges
Published: 2021-02-24
Subjects: Chemistry, Earth Sciences, Physical Sciences and Mathematics
Patawarta Diapir, located in the Central Flinders Ranges, South Australia, has been interpreted as a single allochthonous salt sheet containing Tonian-aged igneous and layered evaporite sedimentary intrasalt inclusions derived from the Callanna Group. Using detailed field mapping, petrographic analysis, and lithostratigraphic correlation within Patawarta Diapir, five primarily silty limestone [...]
Nature of the Cuvier Abyssal Plain crust, offshore NW Australia
Published: 2021-02-24
Subjects: Physical Sciences and Mathematics
Magnetic stripes have long been assumed to be indicative of oceanic crust. However, continental crust heavily intruded by magma can also record magnetic stripes. We re-evaluate the nature of the Cuvier Abyssal Plain (CAP), offshore NW Australia, which hosts magnetic stripes and has previously been defined as oceanic crust. We show chemical data from a basalt within the CAP, previously described [...]