Preprints
Filtering by Subject: Physical Sciences and Mathematics
A proxy-model comparison for mid-Pliocene warm period hydroclimate in the Southwestern US
Published: 2021-10-06
Subjects: Physical Sciences and Mathematics
Hydroclimate proxy reconstructions and paleoclimate models of the mid-Pliocene warm period provide insight into how, under a moderate greenhouse warming scenario, Earth-system feedbacks may impact regional hydroclimate. However, in the Southwestern United States there is discord between these two types of information: proxy data have been interpreted to indicate much wetter conditions, while the [...]
A Mixed, Unified Forward/Inverse Framework for Earthquake Problems: Fault Implementation and Coseismic Slip Estimate
Published: 2021-10-06
Subjects: Earth Sciences, Geophysics and Seismology, Numerical Analysis and Scientific Computing, Physical Sciences and Mathematics, Tectonics and Structure
We introduce a new finite-element (FE) based computational framework to solve forward and inverse elastic deformation problems for earthquake faulting via the adjoint method. Based on two advanced computational libraries, FEniCS and hIPPYlib for the forward and inverse problems, respectively, this framework is flexible, transparent, and easily extensible. We represent a fault discontinuity [...]
New insight on tide-dominated estuary and delta in the Eocene-Miocene Mrayt Group, North-Western Rif, Morocco
Published: 2021-10-05
Subjects: Earth Sciences, Physical Sciences and Mathematics
The sedimentary deposits of Eocene-Miocene Mrayt Group, North-Western Rif, Morocco has been the subject of controversy by previous worksregarding their depositional environments. Detailed sedimentological study based on petrographic study, and sedimentary facies and paleocurrent measurements analysis, leads to several results and new insights. Petrographic study provided the first evidence of [...]
Sustainability without geology? A shortsighted approach
Published: 2021-10-04
Subjects: Education, Life Sciences, Physical Sciences and Mathematics
Over the last few decades, the concept of sustainability has been proposed and championed as the answer to the impending challenges our society will be facing in the future. It has been a rallying opportunity for the broad earth sciences community and a good starting point for such a community to impact societal and policy decisions; however, it has been an opportunity we have largely missed thus [...]
Oblique convergence causes both thrust and strike-slip ruptures during the 2021 M 7.2 Haiti earthquake
Published: 2021-10-01
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
A devastating magnitude 7.2 earthquake struck Southern Haiti on 14 August 2021. The earthquake caused severe damage and over 2000 casualties. Resolving the earthquake rupture process can provide critical insights into hazard mitigation. Here we use integrated seismological analyses to obtain the rupture history of the 2021 earthquake. We find the earthquake first broke a blind thrust fault and [...]
The Effect of Formation Processes on The Frequency of Palaeolithic Cave Sites in Semi-Arid Zones: Insights From Kazakhstan
Published: 2021-10-01
Subjects: Earth Sciences, Geomorphology, Other Environmental Sciences, Physical Sciences and Mathematics, Sedimentology, Social and Behavioral Sciences, Speleology, Stratigraphy
Central Asian caves with Palaeolithic deposits are few but they provide a rich record of human fossils and cultural assemblages that has been used to model Late Pleistocene hominin dispersals. However, previous research has not yet systematically evaluated the formation processes that influence the frequency of Palaeolithic cave sites in the region. To address this deficiency, we combined field [...]
Spacing and Strain During Multiphase Boudinage in 3D
Published: 2021-10-01
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Most models of brittle boudinage predict a dependency of fracture spacing on thickness of the boudinaged layer. This basic relationship can be distorted in the case of multiphase boudinage, where structural inheritance, possibly combined with time evolution of rheology affects boudin geometries, but is not recognized in 2D outcrops. Here we present analyses from a metre-scale, serially sectioned [...]
Mapping riverbed sediment size from Sentinel 2 satellite data
Published: 2021-10-01
Subjects: Physical Sciences and Mathematics
A comprehensive understanding of river dynamics requires quantitative knowledge of the grain size distribution of bed sediments and its variation across different temporal and spatial scales. Several techniques are already available for grain size assessment based on field and remotely sensed data. However, the existing methods are only applicable on small spatial scales and on short time scales. [...]
Tracking Barrier Island Response to Early Holocene Sea-level Rise: High Resolution Study of Estuarine Sediments in the Trinity River Paleovalley
Published: 2021-10-01
Subjects: Physical Sciences and Mathematics
Understanding how barrier islands respond to factors such as variations in sediment supply, relative sea-level rise, and accommodation is valuable for preparing coastal communities for future impacts of climate change. Increasingly, the underlying antecedent topography has been observed to have a significant control on the evolution of the barrier island system by providing increased elevation, [...]
Early Pliocene Marine Transgression into the Lower Colorado River Valley, Southwestern USA, by Re-Flooding of a Former Tidal Strait
Published: 2021-09-29
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Tectonics and Structure
Marine straits and seaways are known to host a wide range of sedimentary processes and products, but the role of marine connections in the development of large river systems remains little studied. This study explores a hypothesis that shallow marine waters flooded the lower Colorado River valley at ~ 5 Ma along a fault-controlled former tidal straight, soon after the river was first integrated [...]
Deterministic model of the eddy dynamics for a midlatitude ocean model
Published: 2021-09-29
Subjects: Physical Sciences and Mathematics
Mesoscale eddies, the weather system of the oceans, although being on the scales of O(20-100 km), have a disproportionate role in shaping the mean stratification, which varies on the scale of O(1000 km). With the increase in computational power, we are now able to partially resolve the eddies in basin-scale and global ocean simulations, a model resolution often referred to as mesoscale [...]
An anisotropic equation of state for high pressure, high temperature applications
Published: 2021-09-25
Subjects: Condensed Matter Physics, Geophysics and Seismology, Materials Science and Engineering, Mineral Physics, Physical Sciences and Mathematics, Planetary Geophysics and Seismology, Planetary Mineral Physics
This paper presents a strategy for consistently extending isotropic equations of state to model anisotropic materials over a wide range of pressures and temperatures under nearly hydrostatic conditions. The method can be applied to materials of arbitrary symmetry. The paper provides expressions for the deformation gradient tensor, the lattice parameters, the isothermal elastic compliance tensor [...]
A survey of storm-induced seaward-transport features observed during the 2019 and 2020 hurricane seasons
Published: 2021-09-24
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Hurricanes are known to play a critical role in reshaping coastlines, particularly on the open ocean coast in cases of overwash, but storm induced seaward-directed flow and responses are often ignored or un-documented. Subaerial evidence for seaward sediment transport (outwash, return-flow) increases our understanding of the impact hurricanes have on coastal and barrier island evolution. Towards [...]
Dam Break Simulation with HEC-RAS and OpenFOAM
Published: 2021-09-22
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
A dam break is a natural disaster that can cause significant property damage and loss of life. It's useful to identify potential flooding areas downstream in the event of a dam break. In this study both HEC-RAS and OpenFOAM are set up to simulate the inundation map downstream of the Dworshak dam in Idaho. Using the same topographical data from satellite observations, similar computational [...]
Missing or Underrated Super-emitters of Nitrogen Oxides in China Exposed from Space
Published: 2021-09-20
Subjects: Environmental Monitoring, Environmental Sciences, Physical Sciences and Mathematics
Nitrogen oxides (NOx ≡ NO + NO2) play a central role in air pollution. Super-emitters present unique opportunities for emission mitigation in China and beyond. They comprise intensive industrial facilities (e.g., power or chemical plants), less than 1 × 1 km2 with high NOx plumes, dominating localized concentrations within a limited geographical scope. However, identification of super-emitters [...]