Filtering by Subject: Earth Sciences
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 [...]
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 [...]
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 [...]
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 [...]
Published: 2023-03-24
Subjects: Earth Sciences, Higher Education
In the last few decades, Geology courses, particularly in the Global North have seen a decline in student enrolment. Geologists have linked this downturn to a lack of exposure to the subject at school and college level. This work seeks to understand the public’s relationship with Geology and draws on over 5000 open-ended question responses to a survey disseminated in 2021. The survey asked both [...]
Published: 2023-03-24
Subjects: Condensed Matter Physics, Earth Sciences, Geophysics and Seismology, Mineral Physics, Planetary Geophysics and Seismology, Planetary Mineral Physics
Published: 2023-03-23
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering
Low-intensity but high-frequency coastal flooding, also known as nuisance flooding, can negatively affect low-lying coastal communities with potentially large socioeconomic effects. This flooding also can greatly affect post-storm coastal dune recovery and reduce the long-term resilience of the back-barrier ecosystem. Recent analytical work has hypothesized that these frequent flooding events are [...]
Published: 2023-03-22
Subjects: Earth Sciences, Environmental Sciences
In the process of mineral nucleation and growth, substrate surface properties and substrate types introduce favorable areas where nucleation events are more likely to occur. The preferential sites for mineral nucleation exist because of the lower interfacial free energy between the precipitating phase and the substrate. In this work, we used a pore-scale Lattice Boltzmann (LB)-based reactive [...]
Published: 2023-03-21
Subjects: Earth Sciences, Environmental Sciences
Crystal nucleation, precipitation, and growth during a reactive fluid flow and solute transport are critical in many natural and industrial systems. Mineral growth is a prime example where (geo)chemical reactions give rise to geometry evolution in porous media. Motivated by the importance of incorporating stochastic dynamics of nucleation, crystallization, and growth kinetics in studying a [...]
Published: 2023-03-21
Subjects: Earth Sciences
Short communication highlighting the rise of preprints in Earth Sciences.
Published: 2023-03-18
Subjects: Earth Sciences
The fossil record of Quaternary reef systems, as expressed in uplifted regions by sequences of stacked terraces, has been extensively used to either understand their morphodynamics, or to unravel sea level variations. Yet, because these two aspects are intimately linked, Quaternary reef analysis is often underdetermined because the analysis often focuses on single sequences, along one-dimensional [...]
Published: 2023-03-17
Subjects: Earth Sciences, Geomorphology
This research utilises Ferdinand von Hochstetter’s unpublished November 1860 Folio of survey data from the first major terrestrial topographical and geological survey in New Zealand. The Folio data enable the reconstruction of the survey across the North Island to Lake Rotomahana, with unique bearings to the lost Pink and White Terraces. Originally prepared for the purposes of cartographic [...]
Published: 2023-03-14
Subjects: Earth Sciences
Large Igneous Provinces (LIPs) have been widely studied over the past decades due to their likely link to mass extinction events. Previous work involving U-Pb zircon dating of the Deccan lava flows indicates that the main phase-2 began 250 Ka before the Cretaceous-Paleogene (K-Pg) mass extinction boundary and continued into the early Danian, suggesting a cause-and-effect relationship. Closer to [...]
Published: 2023-03-14
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
A large non-double-couple component of a tectonic earthquake indicates that its rupture likely was complex and likely involved multiple faults. Detailed source models of such earthquakes can add to our understanding of earthquake source complexity. The 2007 Martinique earthquake in the Caribbean Sea is one of the largest recent earthquakes with a known large non-double-couple component. It was an [...]
Published: 2023-03-14
Subjects: Earth Sciences
On the Greenland Ice Sheet, hydrofracture connects the supraglacial and subglacial hydrologic systems, coupling surface runoff dynamics and ice velocity. Over the last two decades, the growth of low-permeability ice slabs in the firn above the equilibrium line has expanded Greenland’s runoff zone, but the vulnerability of these regions to hydrofracture is still poorly understood. [...]