Preprints
Filtering by Subject: Earth Sciences
Late Glacial and Holocene Palaeolake History of the Última Esperanza Region of Southern Patagonia
Published: 2022-03-29
Subjects: Earth Sciences, Geochemistry, Geology, Geomorphology, Glaciology, Hydrology, Paleobiology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Volcanology
We undertook multiproxy analyses on two sediment cores from Lago Pato, a small lake basin at 51°S topographically separated from Lago del Toro in Torres del Paine (TdP), to provide insights into glacier dynamics and lake level change in the TdP and Última Esperanza region over the last ~30,000 cal a BP (30 ka). Lago Pato is situated in a region overridden by the Southern Patagonian Icefield [...]
Coastal River Response to Transgression: A New Look at the Trinity Incised Valley Using Multi-Resolution Seismic Imaging
Published: 2022-03-29
Subjects: Earth Sciences, Geology, Geomorphology, Geophysics and Seismology, Sedimentology
Modern lowland river systems show transitions in flow characteristics near coastlines that lead to systematic changes in sediment deposition and stratigraphic architecture. Sensitivity of fluvial morphodynamics to base-level has important implications for the prediction and interpretation of fluvial stratigraphy, particularly in deposits formed during periods of relative sea-level rise such as [...]
Stratigraphic architecture of the world’s oldest shale gas play: The 1400-1200 Ma Velkerri and Kyalla formations in the Beetaloo Sub-Basin
Published: 2022-03-29
Subjects: Earth Sciences
The Mesoproterozoic Velkerri and Kyalla formations in the Beetaloo Sub-basin in northern Australia contain the world’s oldest shale plays. In unconventional exploration, the main challenge is the identification of sweet spots from which hydrocarbons can be produced economically. In fine-grained siliciclastic intervals, the distribution of these sweet spots is mainly controlled by the evolution of [...]
Decoupling between strain localisation and the microstructural record revealed by in-situ strain measurements in polycrystalline ice
Published: 2022-03-28
Subjects: Earth Sciences, Glaciology, Tectonics and Structure
We explore the links between strain localisation and microstructural evolution in ice Ih deformed by dislocation creep. Using digital image correlation (DIC), we monitored the evolution of the strain field in two coarse-grained columnar ice samples deformed by creep (uniaxial compression at constant load) at -7 °C and 0.5 MPa up to 9.5% bulk shortening. After a brief transient (<0.2% bulk [...]
Practical Reproducibility in Geography and Geosciences
Published: 2022-03-28
Subjects: Computer Sciences, Earth Sciences, Environmental Sciences, Higher Education
Reproducible research is often perceived as a technological challenge, but it is rooted in the challenge to improve scholarly communication in an age of digitisation. When computers become involved and researchers want to allow other scientists to inspect, understand, evaluate, and build upon their work, they need to create a research compendium that includes the code, data, computing [...]
A state estimate of Siberian summer temperature and moisture availability during the Last Glacial Maximum combining pollen records and climate simulations
Published: 2022-03-26
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology
The Last Glacial Maximum (LGM, ~21.000 years before present) was a period with significantly lower global mean temperature, large Northern Hemisphere ice sheets, and low CO2 concentrations. Unlike other high-latitude areas, Siberia was not covered by a terrestrial ice sheet. Climate simulations with LGM boundary conditions show large inter-model differences especially in Northern Siberia, which [...]
Aerosol-rainfall relationship over the Middle East and North Africa (MENA) region from observations
Published: 2022-03-26
Subjects: Earth Sciences
Water is an essential element of life and rainfall. The amount of rainfall directly affects the spatial and temporal distribution of water resources on the Earth. Rainfall has direct impact on agricultural production, daily life activities, and human health. Atmospheric aerosols are essential for rainfall formation; therefore, understanding how dust compositions and distributions affect the [...]
Greenland ice sheet vulnerability under diverse climatic warming scenarios
Published: 2022-03-26
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Sea-level rise of even one meter will have drastic global impacts. Melting the Greenland Ice Sheet (GIS) would raise sea level by 7.4 meters. There is an urgent need to improve predictions of how quickly the GIS will contribute its first meter of sea-level rise, and from where on the ice sheet that water will come. Estimating the volume of Greenland ice that was lost during past warm periods [...]
Geochronology and formal stratigraphy of the Sturtian Glaciation in the Adelaide Superbasin
Published: 2022-03-24
Subjects: Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy
The glaciogenic nature of the Yudnamutana Subgroup was first recognized over a century ago, and its global significance was recognized shortly after, with the eventual postulation of a global Sturtian Glaciation and Snowball Earth theory. Much debate on the origin and timing of these rocks, locally and globally, has ensued in the years since. A significant corpus of research on the lithology, [...]
Climate sensitivity & resistance since the Industrial Revolution
Published: 2022-03-22
Subjects: Earth Sciences
Climate sensitivity is a fundamental yet uncertain metric of Earth’s response to anthropogenic forcing; its temporal evolution in particular is poorly constrained yet critical for leveraging historical observations for future projections. A Bayesian energy balance model indicates a 83% (84%) probability that the climate sensitivity increased (decreased) from 1900-1940 (1940-2010). These trends [...]
A source model for earthquakes near the nucleation dimension
Published: 2022-03-22
Subjects: Earth Sciences, Physical Sciences and Mathematics
Earthquake self-similarity is a controversial topic, both observationally and theoretically. Theory predicts a finite nucleation dimension, implying a break of self-similarity below a certain magnitude. While observations of non self-similar earthquake behavior have been reported, their interpretation is challenging due to trade-offs between source and path effects and assumptions on the [...]
Mid- to Late Neoproterozoic Development and Provenance of the Adelaide Superbasin
Published: 2022-03-22
Subjects: Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy, Tectonics and Structure
Late Tonian sequences of the Adelaide Superbasin were witness to the birth of the proto-Pacific Ocean during the breakup of Rodinia. Understanding the sedimentology and provenance of these rocks from across the basin is key to understanding their deposition over c. 70 million years, the local palaeogeography, and leads to a better understanding of the early development of the proto-Pacific Ocean. [...]
Reducing the Uncertainty of Multi-Well Petrophysical Interpretation from Well Logs via Machine-Learning and Statistical Models
Published: 2022-03-22
Subjects: Analysis, Earth Sciences, Engineering, Geophysics and Seismology, Mining Engineering, Multivariate Analysis, Statistical Methodology, Statistical Models
Well-log interpretation provides in situ estimates of formation properties such as porosity, hydrocarbon pore volume, and permeability. Reservoir models based on well-log-derived formation properties deliver reserve-volume estimates, production forecasts, and help with decision making in reservoir development. However, due to measurement errors, variability of well logs due to multiple [...]
Automated machine learning to evaluate the information content of tropospheric trace gas columns for fine particle estimates over India: a modeling testbed
Published: 2022-03-20
Subjects: Artificial Intelligence and Robotics, Atmospheric Sciences, Civil and Environmental Engineering, Computer Sciences, Earth Sciences, Environmental Engineering, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology
India is largely devoid of high-quality and reliable on-the-ground measurements of fine particulate matter (PM2.5). Ground-level PM2.5 concentrations are estimated from publicly available satellite Aerosol Optical Depth (AOD) products combined with other information. Prior research has largely overlooked the possibility of gaining additional accuracy and insights into the sources of PM using [...]
Internal Planetary Feedbacks, Mantle Dynamics, and Plate Tectonics
Published: 2022-03-18
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Planetary Geophysics and Seismology, Planetary Sciences, Tectonics and Structure
Isolating planetary feedbacks, and feedback analysis, are prevalent aspects of climate and Earth surface process science. An under appreciation of internal planet feedbacks, and feedback analysis for plate tectonics research, motivate this chapter. We review feedbacks that influence the Earth's thermal evolution and expand them to include magmatic history and planetary water budgets. The [...]