Preprints
Filtering by Subject: Earth Sciences
Gap Filling of High-Resolution Soil Moisture for SMAP/Sentinel-1: A Two-Layer Machine Learning-Based Framework
Published: 2019-02-11
Subjects: Artificial Intelligence and Robotics, Computer Sciences, Earth Sciences, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
As the most recent 3 km soil moisture product from the Soil Moisture Active Passive (SMAP) mission, the SMAP/Sentinel-1 L2_SM_SP product has a unique capability to provide global-scale 3 km soil moisture estimates through the fusion of radar and radiometer microwave observations. The spatial and temporal availability of this high-resolution soil moisture product depends on concurrent radar and [...]
Further evidence for magmatic bias in 14C dating of the Taupo and other major eruptions: response to Hogg et al. https://eartharxiv.org/7r5jp/
Published: 2019-02-11
Subjects: Earth Sciences, Physical Sciences and Mathematics, Volcanology
We appreciate the opportunity to respond to Hogg et al.’s critique of HDK182. We consider that neither the arguments nor the additional data presented by Hogg et al. provides a basis for rejecting our hypothesis of magmatic carbon bias in proximal 14C ages for the Taupo eruption. Hogg et al. focus on the wiggle match and Kaipo Bog dates out of > 40 data points, whereas our paper focused on the [...]
Heavy rainfall in Paraguay during the 2015-2016 austral summer: causes and sub-seasonal-to-seasonal predictive skill
Published: 2019-02-11
Subjects: Atmospheric Sciences, Civil and Environmental Engineering, Climate, Earth Sciences, Engineering, Environmental Engineering, Environmental Sciences, Hydrology, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Water Resource Management
During the austral summer 2015/16, severe flooding displaced over 170 000 people on the Paraguay River system in Paraguay, Argentina, and southern Brazil. These floods were driven by repeated heavy rainfall events in the lower Paraguay River basin. Alternating sequences of enhanced moisture inflow from the South American low-level jet and local convergence associated with baroclinic systems were [...]
Surface Wave Imaging using Distributed Acoustic Sensing Deployed on Dark Fiber: Moving Beyond High Frequency Noise
Published: 2019-02-08
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Several recent studies have demonstrated that Distributed Acoustic Sensing (DAS) can utilize existing subsurface telecom fiber (i.e. dark fiber) for high quality seismic measurements. Researchers to date have shown that this sensing combination, coupled to ambient noise interferometry techniques, can effectively image the shallow subsurface (< 30 m) using vehicle and infrastructure noise (f = [...]
Geochemical characterisation of the Late Quaternary widespread Japanese tephrostratigraphic markers and correlations to the Lake Suigetsu sedimentary archive (SG06 core)
Published: 2019-02-07
Subjects: Earth Sciences, Physical Sciences and Mathematics, Volcanology
Large Magnitude (6-8) Late Quaternary Japanese volcanic eruptions are responsible for widespread ash (tephra) dispersals providing key isochrons suitable for the synchronisation and dating of palaeoclimate archives across East Asia, the NW Pacific and beyond. The transfer of geochronological information using these eruption deposits demands robust tephra correlations underpinned by detailed and [...]
Protracted thermal evolution of the Neoproterozoic Araçuaí hot orogen (SE Brazil): consequences for rheology, strain distribution, and deformation analysis
Published: 2019-02-07
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
The Araçuaí-Ribeira belt formed during the amalgamation of West Gondwana in the late Neoproterozoic. Its evolution encompasses a main tectono-metamorphic peak at 600-580 Ma and a minor one, associated with the final collision with the Western Congo at 540-530 Ma. This belt holds characteristics of a hot-orogen: high thermal gradient (>30 °C/km), pervasive partial melting of the middle crust, [...]
An investigation into the role of time-dependent cohesion in interseismic fault restrengthening
Published: 2019-02-07
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
Earthquakes typically exhibit recurrence times that far exceed time-scales attainable in a laboratory setting. To traverse the temporal gap between the laboratory and nature, the slide-hold-slide test is commonly employed as a laboratory analogue for the seismic cycle, from which the time-dependence of fault strength may be assessed. In many studies it is implicitly assumed that all fault [...]
Influence of grain boundary structural evolution on pressure solution creep rates
Published: 2019-02-06
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
Intergranular pressure solution is a well-known rock deformation mechanism in wet regions of the upper crust, and has been widely studied, especially in the framework of compaction of granular materials, such as reservoir sandstones and fault rocks. Several analytical models exist that describe compaction creep by stress-induced mass transport, and the parameters involved are relatively well [...]
Dynamic Rupture Propagation on Fault Planes with Explicit Representation of Short Branches
Published: 2019-02-06
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Active fault zones are homes for a plethora of complex structural and geometric features that are expected to affect earthquake rupture nucleation, propagation, and arrest, as well as interseismic deformation. Simulation of these complexities have been largely done using continuum plasticity or scalar damage theories. In this paper, we use a highly efficient novel hybrid finite element-spectral [...]
Connecting fluvial levee deposition to flood-basin hydrology
Published: 2019-02-06
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
In this study we seek to understand the controls on where levees form and what sets their size and shape.
The Future of Broadband Passive Seismic Acquisition
Published: 2019-02-06
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
It is an exciting time to be a seismologist. In November 2018, the InSight lander touched down on Mars and the first seismometer was deployed on another planet. This incredible feat means planetary seismologists are currently searching for marsquakes and will hopefully soon be providing images of its interior and helping us to understand how rocky planets form. However, we have been doing this [...]
Effect of fault roughness on aftershock distribution: Plastic off-fault material properties
Published: 2019-02-04
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We perform spontaneous earthquake rupture simulations on rough strike- slip faults with off-fault plastic material properties. We examine the off-fault stress change and damage pattern resulting from dynamic fault slip in the near-fault region. We use the stress output from each simulation to calculate the Coulomb failure function (CFF). We calculate the CFF values at the extensional side of the [...]
Globally Standardized MODIS Spectral Mixture Models
Published: 2019-01-31
Subjects: Earth Sciences, Environmental Monitoring, Environmental Sciences, Other Earth Sciences, Physical Sciences and Mathematics
This analysis presents standardized substrate, vegetation, and dark (S, V, & D) endmembers (EMs) for spectral mixture analysis (SMA) of MODIS daily nadir-looking BRDF-adjusted reflectance (daily NBAR) data. MODIS daily NBAR EMs are derived from a diverse collection of over 43 million MODIS spectra spanning 6 continents and all non-polar biomes. EM spectra found in the study are comparable to [...]
Carbonate and silicate intercomparison materials for cosmogenic 36Cl measurements
Published: 2019-01-31
Subjects: Earth Sciences, Physical Sciences and Mathematics
Two natural mineral separates, labeled CoCal-N and CoFsp-N, have been prepared to serve as intercomparison material (ICM) for in situ-produced cosmogenic 36Cl and natural chlorine (Clnat) analysis. The sample CoCal-N is derived from calcite crystals in a Namibian lag deposit, while the sample CoFsp-N is derived from a single crystal of alkali-feldspar from a Namibian pegmatite. The sample [...]
Beo v1.0: Numerical model of heat flow and low-temperature thermochronology in hydrothermal systems
Published: 2019-01-29
Subjects: Earth Sciences, Geochemistry, Geology, Hydrology, Physical Sciences and Mathematics
Low-temperature thermochronology can provide records of the thermal history of the upper crust and can be a valuable tool to quantify the history of hydrothermal systems. However, existing model codes of heat flow around hydrothermal systems do not include low-temperature thermochronology. Here I present a new model code that simulates thermal history around hydrothermal systems on geological [...]