Preprints
Filtering by Subject: Earth Sciences
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 [...]
Examining the power supplied to Earth's dynamo by magnesium precipitation and radiogenic heat production
Published: 2023-04-06
Subjects: Earth Sciences, Geophysics and Seismology, Mineral Physics, Physical Sciences and Mathematics, Planetary Sciences
We examine magnesium and potassium solubility in liquid Fe mixtures, representative of Earth’s core composition, in equilibrium with liquid silicate mixtures representative of an early magma ocean. Our study is based on the calculation of the chemical potentials of MgO and K2O in both phases, using density functional theory. For MgO, we also study stability against precipitation of the solid [...]
Compressibility of ferropericlase at high-temperature: evidence for the iron spin crossover in seismic tomography
Published: 2023-04-06
Subjects: Earth Sciences, Geophysics and Seismology, Mineral Physics
The iron spin crossover in ferropericlase, the second most abundant mineral in Earth’s lower mantle, causes changes in a range of physical properties, including seismic wave velocities. Understanding the effect of temperature on the spin crossover is essential to detect its signature in seismic observations and constrain its occurrence in the mantle. Here, we report the first experimental results [...]
Spatio-temporal variability of small-scale leads based on helicopter winter sea ice surface temperatures
Published: 2023-04-06
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology
Surface temperature is crucial in studying the Arctic climate, particularly during winter. We examine 1 m resolution surface temperature maps of 35 helicopter flights between 02 October 2019 and 23 April 2020, recorded during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC). The seasonal cycle of the average surface temperature spans from 265.6 K on 02 October [...]
DiadFit: An Open-Source Python3 Tool for Peak fitting of Raman Data from silicate melts and CO2 fluids
Published: 2023-04-04
Subjects: Earth Sciences, Geology, Mineral Physics, Physical Sciences and Mathematics, Volcanology
We present DiadFit - an open-source Python3 tool for efficient processing of Raman spectroscopy data collected from fluidinclusions, melt inclusions and silicate melts. DiadFit is optimized to fit the characteristic peaks from CO2 fluids (Fermi diads,hot bands, 13C), gas species such as SO2, N2, solid precipitates (e.g., carbonates), and Ne emission lines with easily tweakablebackground positions [...]
Complex seabed geomorphology shaped by various oceanographic processes: a case study from the Gippsland Basin, offshore south-eastern Australia
Published: 2023-04-04
Subjects: Earth Sciences, Geology, Geomorphology, Sedimentology
The Gippsland Basin is located in the southeastern continental margin of Australia and hosts a variety of important marine resources. Recent high-resolution seabed mapping reveals that seabed morphology is extremely complex in different regions of the Gippsland Basin (i.e. northern, central and southern regions), ranging from scarps, cyclic step trains, channels, canyons, gullies, and giant [...]
Features of crevasse splay deposits and sedimentary processes associated with levee breaching by the October 2019 flood of the Chikuma River, Central Japan
Published: 2023-03-31
Subjects: Earth Sciences, Sedimentology
Field investigations and analyses of modern crevasse splay deposits can both elucidate the processes of levee breaching and help to identify past crevasse splay deposits from geologic strata, thereby estimating the magnitudes of ancient river floods. In this study, we studied levee breach processes and crevasse splay deposits in order to determine the distribution characteristics of the [...]
The Application of CNN-Based Image Segmentation for Tracking Coastal Erosion and Post-Storm Recovery
Published: 2023-03-31
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Geomorphology
Coastal erosion due to extreme events can cause significant damage to coastal communities and deplete beaches. Post-storm beach recovery is a crucial natural process that rebuilds coastal morphology and reintroduces eroded sediment to the subaerial beach. However, monitoring the beach recovery, which occurs at various spatiotemporal scales, presents a significant challenge. This is due to, [...]
Widespread Wood Placement and Regrading Drive Lateral Connectivity and Reworking of the Channel and Floodplain in a Valley Bottom Reset to Stage 0
Published: 2023-03-31
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Valley bottom process reset, or the excavation of high surfaces and fill of incised channels combined with large wood addition, is a new method for creating multi-channel river-wetland corridors (also referred to as Stage 0 valley bottoms). Valley bottom process reset seeks to increase lateral flow and sediment connectivity to retain flow and sediment and kickstart geomorphic processes that may [...]
Stationary surface waves and antidunes in dense pyroclastic density currents
Published: 2023-03-28
Subjects: Earth Sciences, Sedimentology, Volcanology
Stationary antidunes are a product of critical flow in open channel systems, but with poor preservation potential. They are related to the existence of stationary surface waves in the overriding current, but their existence in the dense pyroclastic density current regime has been unrecognized to date. Experiments presented here demonstrate that surface waves in simulated dense pyroclastic density [...]
Bayesian estimation of nonlinear centroid moment tensors using multiple seismic data sets
Published: 2023-03-27
Subjects: Earth Sciences, Geophysics and Seismology
Centroid moment tensor (CMT) parameters of earthquakes are routinely estimated to gain information on structures and regional tectonics. However, for small earthquakes (M<4), it is still challenging to determine CMTs due to the lack of high-quality waveform data. In this study, we propose to improve solutions for small earthquakes by incorporating multiple seismic data types in Bayesian joint [...]
Linking the core heat content to Earth's accretion history
Published: 2023-03-26
Subjects: Earth Sciences, Geochemistry, Geophysics and Seismology, Planetary Geochemistry, Planetary Geophysics and Seismology
In this study we use a parameterized model of differentiation in a magma ocean setting, in which the magma ocean depth evolves during accretion, to predict the composition of the primordial core. We couple this chemical model to a thermal evolution model of the accreting metal to estimate the Earth's core heat content at the end of its formation. We find geochemically consistent models. All these [...]
N-S versus E-W extension in the Tibetan plateau: Are they driven by the same dynamics?
Published: 2023-03-25
Subjects: Earth Sciences, Physical Sciences and Mathematics
The tectonic history of the Himalaya-Tibet Mountain Range records two important extensional tectonic events: 1) N-S extension in the Himalaya-Tibet transition zone, and 2) E-W extension in the southern and central Tibet, manifested in the form of east-west and north-south striking normal faults, respectively. The N-S extensional event (~22 Ma) started to commence earlier than the E-W extension [...]