Preprints
Filtering by Subject: Earth Sciences
The Future of Developed Barrier Systems - Part II: Alongshore Complexities and Emergent Climate Change Dynamics
Published: 2023-10-11
Subjects: Earth Sciences
Developed barrier systems (barrier islands and spits) are lowering and narrowing with sea-level rise (SLR) such that habitation will eventually become infeasible or prohibitively expensive in its current form. Before reaching this state, communities and other entities will make choices, in the face of changing climate conditions, to modify the natural and built environment to reduce relatively [...]
The Heavy Mineral Map of Australia Project: A Novel, Rapid, Automated Quantitative Mineralogy Workflow
Published: 2023-10-10
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics
The Heavy Mineral Map of Australia (HMMA) is the world’s first project aiming to define a continental heavy mineral baseline. It utilises a novel sample processing workflow and automated mineralogy techniques to rapidly generate and analyse mineralogical data from 1315 archived samples of catchment outlet sediments collected from 1186 catchments across the Australian continent. Heavy [...]
Field Report No. 3 - Tabor Tree Project Summary Report 2021
Published: 2023-10-10
Subjects: Adult and Continuing Education, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Environmental Studies, Outdoor Education, Physical Sciences and Mathematics
“The Friends of Mt. Tabor Park (FMTP) was organized as a non-profit group* in 2000. Our pur- pose is to improve and help maintain Mt. Tabor Park for the benefit of individuals, organizations and the Park Bureau; to identify and help solve problems; and to participate in park planning projects.”(FMTP) During the winter of 2021 with covid closures of the Visitor Center, Tree Medicine hikes were [...]
Field Report No. 2 - Tabor Tree Project: Citizen Scientists Training
Published: 2023-10-10
Subjects: Adult and Continuing Education, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Outdoor Education, Physical Sciences and Mathematics
“NASA’s citizen science projects are collaborations between scientists and interested members of the public. Through these collaborations, volunteers (known as citizen scientists) have helped make thou- sands of important scientific discoveries.” (NASA) In January 2021, using the GLOBE Observer app, the Mt. Tabor community joined this global network of scientists, students, teachers, hikers, and [...]
Field Report No. 1 - Tabor Tree Project Report 2021
Published: 2023-10-10
Subjects: Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Environmental Studies, Nature and Society Relations, Other Plant Sciences
In this Survey, the Tabor Tree Project identified 130 trees randomly in all 12 zones of the park called Mt. Tabor in Portland, Oregon. The Majority of the Trees at Mt. Tabor Park are conifers, and specifically Douglas Fir who can live longer than 1,000 years. The oldest one in the park is 496 years old, and sprouted sometime around 1520 AD. Through the efforts of Tree Medicine hikes and Citizen [...]
Rano Kao & Ava Ranga Uka: Rapa Nui Report 2014
Published: 2023-10-10
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Environmental Sciences, Fresh Water Studies
29 March 2014 Objective: Sampling and testing Rano Kao water depth, evaporation and volume. Compare with previous results from 2005, 2008 and 2014 coring expeditions and detect the rate of change in lake water evaporation as compared to Global Meteoric Water Line.
The influence of fluid inclusions, organics, and calcite fabric on trace element distributions in stalagmites
Published: 2023-10-09
Subjects: Earth Sciences, Physical Sciences and Mathematics
Growing stalagmites entrap water and organic molecules while incorporating trace elements in diverse crystallographic fabrics. However, the interrelationships between crystal defects, fluid inclusions, organic carbon incorporation, and trace element incorporation in stalagmites remain poorly constrained. Here we use for the first time Fourier Transformation Infrared Focal-Plane Array (FTIR-FPA) [...]
Progression of the surge in the Negribreen Glacier System from two years of ICESat-2 measurements
Published: 2023-10-08
Subjects: Applied Mathematics, Earth Sciences, Physical Sciences and Mathematics
The unique measurement capabilities of ICESat-2 allow high spatiotemporal resolution of complex ice-dynamic processes that occur during a surge. Detailed and precise mapping of height changes on surge glaciers has previously escaped observations from space due to limited resolution of space-borne altimeter data and the surface characteristics of glaciers during surge such as heavy crevassing. [...]
The importance of anisotropic viscosity in numerical models for olivine textures in shear and subduction deformations
Published: 2023-10-05
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Olivine lattice preferred orientation (LPO), or texture, forms in relation to deformation mechanisms such as dislocation creep and can be observed in the upper mantle as seismic anisotropy. Olivine is also mechanically anisotropic, meaning that it responds to stresses differently depending on the direction of the stress. Understanding the interplay between anisotropic viscosity (AV) and LPO, and [...]
Monitoring surface deformation with spaceborne radar interferometry in landslide complexes: insights from the Brienz/Brinzauls slope instability, Swiss Alps
Published: 2023-10-05
Subjects: Earth Sciences
We performed an extensive analysis of C-Band SAR datasets provided by the European Space Agency (ESA) satellites ERS-1/2, Envisat ASAR, and Sentinel-1 in the period 1992-2020 aiming at reconstructing the multi-decadal spatial and temporal evolution of the surface displacements at the Brienz/Brinzauls landslide complex, located in canton Graubünden (Switzerland). To this end, we analyzed about [...]
A shift in the Sr isotopic composition of the magmatic source triggering 2019 paroxysmal eruptions at Stromboli Volcano
Published: 2023-10-05
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Volcanology
The persistent volcanic activity of Stromboli Volcano, Aeolian Islands, Italy, is interrupted by paroxysmal eruptions on a decadal interval. In 2019, two strong paroxysms on July 3rd and August 28th, ended a more than a decade long period of regular strombolian activity. During normal strombolian activity the volcano erupts highly porphyritic scoria and lava (HP)20 with a shoshonitic basalt [...]
Complementary classifications of aeolian dunes based on morphology, dynamics, and fluid mechanics
Published: 2023-10-03
Subjects: Earth Sciences, Fluid Dynamics, Geomorphology, Other Earth Sciences, Physical Sciences and Mathematics, Physics, Planetary Geomorphology, Planetary Sciences, Sedimentology
Dunes form where winds blow over a bed of mobile sediment grains – conditions that are common in our solar system. On Earth, dunes abound in arid continental interiors and along sandy coastlines. Dune fields have also been recognized on Venus, Mars, Saturn's moon Titan, and Pluto. In response to the different boundary conditions and other environmental forcings, dunes adopt a rich diversity [...]
Geological evidence confirms the staircase patterns of Earth’s rotation deceleration from the Neoproterozoic to the Mesozoic Era
Published: 2023-10-02
Subjects: Earth Sciences, Environmental Sciences
Due to tidal dissipation, the Earth’s rotation has been slowing down, but the past rates of this process remain subject of debate. Here we conducted a comprehensive cyclostratigraphic analysis of eight geological datasets to further constrain the Earth's rotation history from the Neoproterozoic to Mesozoic. Our results allow us to further test theoretical physical tidal models, and support a [...]
Revisiting oxygen-18 and clumped isotopes in planktic and benthic foraminifera
Published: 2023-09-26
Subjects: Earth Sciences, Environmental Sciences
Foraminiferal isotopes are widely used to study past oceans, with different species recording conditions at different depths. Their δ18O values record both seawater oxygen-18 and temperature according to species-specific fractionation factors, while their Δ47 signatures likely depend only on temperature. We describe an open-source framework to collect/combine data relevant to foraminiferal [...]
The Balanced Billion
Published: 2023-09-26
Subjects: Earth Sciences
There is a mid-Proterozoic stretch of Earth’s history (roughly 1.9–0.9 Ga) called, non-affectionately, the “boring billion”. The moniker was first inspired several decades ago by the apparent absence of any significant carbon isotope anomalies and was linked to the relatively “boring” interval in between Earth’s broadly two-step pattern in atmospheric oxygenation. However, in light of (i) the [...]