Preprints
There are 4721 Preprints listed.
Controls of the lithospheric thermal field of an ocean-continent subduction zone: the southern Central Andes
Published: 2021-12-08
Subjects: Earth Sciences
In an ocean-continent subduction zone, the assessment of the lithospheric thermal state is essential to determine the controls of the deformation within the upper plate and the dip angle of the subducting lithosphere. In this study, we evaluate the degree of influence of both the configuration of the upper plate and variations of the subduction angle on the lithospheric thermal field of the [...]
Small artificial impoundments have big implications for hydrology and freshwater biodiversity
Published: 2021-12-07
Subjects: Biodiversity, Civil and Environmental Engineering
Headwater streams are critical for freshwater ecosystems. Global and continental studies consistently show major dams as dominant sources of hydrological stress threatening biodiversity in the world’s major rivers, but cumulative impacts from small artificial impoundments concentrated in headwater streams have rarely been acknowledged. Using the Murray Darling River basin (Australia) and the [...]
The challenge of setting ‘climate ready’ ecological targets for environmental flow planning
Published: 2021-12-07
Subjects: Biodiversity, Civil and Environmental Engineering, Other Life Sciences
Implementing environmental flows has emerged as a major restoration tool for addressing the impacts of hydrologic alteration in large river systems. The ‘natural flow paradigm’ has been a central guiding principle for determining important ecohydrological relationships. Yet, climate change and associated changes in rainfall run off relationships, seasonality of flows, disruptions to food webs and [...]
What’s obstructing climate change adaptation in environmental water management?
Published: 2021-12-07
Subjects: Biodiversity, Civil and Environmental Engineering, Other Life Sciences
Climate change is irreversibly changing the water cycle, yet existing environmental flow assessment methods often fail to recognise the non stationarity of hydro climatic systems. Failure to do so will lead to the inability of environmental water management to achieve its restoration targets. Australia has undergone major reform over the past twelve years to recover water from consumptive use for [...]
Improving Urban Seismic Risk Estimates for Bishkek, Kyrgyzstan, Incorporating Recent Geological Knowledge of Hazards
Published: 2021-12-07
Subjects: Geology, Geomorphology, Tectonics and Structure
Many cities are built on or near active faults, which pose seismic hazard and risk to the urban population. This risk is exacerbated by city expansion, which may obscure signs of active faulting. Here we estimate the risk to Bishkek city, Kyrgyzstan, due to realistic earthquake scenarios based on historic earthquakes in the region and improved knowledge of the active faulting. We use previous [...]
Continuous cultivation of the lithoautotrophic nitrate-reducing Fe(II)-oxidizing culture KS in a chemostat bioreactor
Published: 2021-12-07
Subjects: Biogeochemistry
Laboratory-based studies on microbial Fe(II) oxidation are commonly performed over just a few weeks in small volumes with high substrate concentrations, resulting in geochemical gradients and volumetric effects caused by sampling. We used a chemostat to enable uninterrupted supply of medium, and investigated autotrophic growth of the nitrate-reducing Fe(II)-oxidizing culture KS for 24 days. We [...]
A conceptual geological model for offshore wind sites in palaeo ice stream settings: The Utsira Nord site, North Sea
Published: 2021-12-06
Subjects: Physical Sciences and Mathematics
Conceptual geological models of the shallow subsurface which integrate geological and geotechnical information are important for more strategic data acquisition and engineering at offshore wind sites. Utsira Nord is an offshore wind site in the Norwegian North Sea. It covers an area of 23 km x 43 km within the Norwegian Channel palaeo ice stream, with an average water depth of 267 m making the [...]
Unusual Suspects: “Allies in the Park, Are Closer Than They Appear”
Published: 2021-12-06
Subjects: Life Sciences, Social and Behavioral Sciences
One season, 1039 hours, as a Park Ranger at Mesa Verde National Park. Interps we are called, observing, telling stories, being stewards of the past, present and future of wildness. Wildness in the animal world is reserved to only 4% of the planets millions of animals, Wildness is why people come to the National Parks, they are the last stronghold of beauty that bears presence in each of our [...]
COVID-19 Impacts Highlight the Need for Holistic Evaluation of Research in the Hydrologic Sciences
Published: 2021-12-06
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
As we reckon with the effect of COVID-19 on the research enterprise in hydrologic science, it is important to acknowledge that disruptions will be persistent and that institutional-level adjustments, while helpful, are not sufficient to mitigate all impacts on hydrologic scientists. Here, we describe the breadth of research contributions in the hydrologic sciences, consider how the pandemic has [...]
Developing an internally consistent methodology for K-feldspar MAAD TL thermochronology
Published: 2021-12-06
Subjects: Geology
Luminescence thermochronology and thermometry can quantify recent changes in rock exhumation rates and rock surface temperatures, but these methods require accurate determination of several kinetic parameters. For K-feldspar thermoluminescence (TL) glow curves, which comprise overlapping signals of different thermal stability, it is challenging to develop measurements that capture these parameter [...]
Environmental Flows Assessments in the face of uncertainty: supporting the adaptive management of environmental flows
Published: 2021-12-06
Subjects: Civil and Environmental Engineering, Other Life Sciences
Adaptive management has become the preferred approach for managing environmental flows globally, and successful implementation recognizes multiple dimensions of variability and complexity in socio-ecological systems. This paper outlines an environmental flow assessment methodology that explicitly addresses the uncertainty and change inherent in adaptively managing multiple values for management [...]
Evaluating essential features of proppant transport at engineering scales combining field measurements with machine learning algorithms
Published: 2021-12-06
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Sciences, Geology, Hydraulic Engineering, Oil, Gas, and Energy, Sustainability
The characterization of the proppant transport at a field-engineering scale is still challenging due to the lack of direct subsurface measurements. Features that control the proppant transport may link the experimental and numerical observations to the practical operations at a field scale. To improve the numerical and laboratory simulations, we propose a machine-learning-based workflow to [...]
Integrated framework for rapid climate stress testing on a monthly timestep
Published: 2021-12-06
Subjects: Civil and Environmental Engineering
“Bottom-up” methods are increasingly used to assess the vulnerability of water systems to climate change. Central to these methods is the climate “stress test”, where the system is subjected to various climatic changes to test for unacceptable outcomes. We present a framework for climate stress testing on a monthly timestep, suitable for systems whose dominant dynamic is seasonal or longer (eg. [...]
Spatio-temporal clustering of seismicity enabled by off-fault plasticity
Published: 2021-12-06
Subjects: Applied Mechanics, Civil and Environmental Engineering, Dynamics and Dynamical Systems, Earth Sciences, Engineering, Engineering Mechanics, Engineering Science and Materials, Geophysics and Seismology, Mechanical Engineering, Mechanics of Materials, Other Mechanical Engineering, Physical Sciences and Mathematics, Tribology
While significant progress has been made in understanding earthquake source processes in linear elastic domains, the effect of more realistic rheologies including plasticity is poorly understood. Here, we simulate sequence of earthquake and aseismic slip of a 2D antiplane rate-and-state fault embedded in a full-space elastic-plastic bulk. We show that off-fault plasticity may lead to partial [...]
Sequences of seismic and aseismic slip on bimaterial faults show dominant rupture asymmetry and potential for elevated seismic hazard
Published: 2021-12-06
Subjects: Physical Sciences and Mathematics
We perform numerical simulations of sequences of earthquake and aseismic slip on planar rate and state faults separating dissimilar material within the 2-D plane strain approximation. We resolve all stages of the earthquake cycle from aseismic slip to fast ruptures while incorporating full inertia effects during seismic event propagation. We show that bimaterial coupling results in favorable [...]