Preprints
There are 7992 Preprints listed.
Performance of terrestrial laser scanning to characterize managed Scots pine (Pinus sylvestris L.) stands is dependent on forest structural variation
Published: 2020-03-05
Subjects: Forest Sciences, Life Sciences
There is a limited understanding of how forest structure affects the performance of methods based on terrestrial laser scanning (TLS) in characterizing trees and forest environments. We aim to improve this understanding by studying how different forest management activities that shape tree size distributions affect the TLS-based forest characterization accuracy in managed Scots pine (Pinus [...]
On the formation of oceanic detachment faults and their influence on intra-oceanic subduction initiation: 3D thermomechanical modeling
Published: 2020-03-04
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Extensional detachment faults, which have been widely documented in slow-spreading and ultraslow-spreading ridges on Earth, can effectively localize deformation due to their weakness. After the onset of oceanic closure, these weak oceanic detachments may directly control the nucleation of a subduction zone parallel to the former mid-ocean ridge, as is suggested for the Neotethys in Middle [...]
Use of geochemical fingerprints to trace sediment sources in an agriculture catchment of Argentina
Published: 2020-03-04
Subjects: Environmental Sciences, Natural Resources and Conservation, Physical Sciences and Mathematics
Soil erosion and associated sediment redistribution are key environmental problems in Central Argentina. Specific land uses and management practices, such as intensive grazing and crop cultivation, are considered significantly driving and accelerating these processes. This research focuses on the identification of suitable soil tracers from hot spots of land degradation and sediment fate in an [...]
Global inventories of inverted stream channels on Earth and Mars
Published: 2020-03-04
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics
Data from orbiting and landed spacecraft have provided vast amounts of information regarding fluvial and fluvial-related landforms and sediments on Mars. One variant of these landforms are sinuous ridges that have been interpreted to be remnant evidence for ancient fluvial activity, observed at hundreds of martian locales. In order to further understanding of these martian landforms, this paper [...]
Northern peatland depth and lateral expansion is inconsistent with a 1055 GtC estimate of carbon storage
Published: 2020-03-04
Subjects: Life Sciences, Other Life Sciences
Peatlands contain one of the largest stores of terrestrial carbon and exert a considerable influence on the global climate cycle. However, both the magnitude of the peatland carbon pool and the development of this pool through time are poorly constrained. In a recently published article, Nichols and Peteet combine basal radiocarbon dates from palaeoecological studies with previously published [...]
Reply to “Global coastal wetland expansion under accelerated sea-level rise is unlikely”
Published: 2020-03-05
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics, Sustainability
We thank Törnqvist et al. for engaging with our modelling study on the future response of global coastal wetlands to sea-level rise (SLR) and their careful and critical discussion of the presented methods and results. However, we disagree with their suggestion that our modelling approach is inadequate, a claim which relies on two arguments: (1) they argue that our results are inconsistent with [...]
Stress drop variation of deep-focus earthquakes based on empirical Greens function
Published: 2020-03-04
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We analyze source characteristics of global, deep-focus (> 350 km) earthquakes with moment magnitudes (Mw) larger than 6.0-8.2 using teleseismic P-wave and S-wave spectra and an empirical Greens functions approach. We estimate the corner frequency assuming Brunes source model and calculate stress drops assuming a circular crack model. Based on P-wave and S-wave spectra, the one-standard [...]
Analytical prediction of seismicity rate due to tides and other oscillating stresses
Published: 2020-03-03
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Planetary Geophysics and Seismology, Planetary Sciences, Tectonics and Structure
Oscillatory stresses are ubiquitous on earth and other solid-surface bodies. Tides and seasonal signals perpetually stress faults in the crust. Relating seismicity to these stresses offers fundamental insight into earthquake triggering. We present a simple model that describes seismicity rate due to perpetual oscillatory stresses. The model applies to large amplitude, non-harmonic, and [...]
Dynamic fault interaction during a fluid-injection induced earthquake: The 2017 Mw 5.5 Pohang event
Published: 2020-03-03
Subjects: Earth Sciences, Geophysics and Seismology, Life Sciences, Physical Sciences and Mathematics
The November 15th, 2017 Mw 5.5 Pohang earthquake (South Korea) has been linked to hydraulic stimulation and fluid injections, making this the largest induced seismic event associated with an Enhanced Geothermal System (EGS). To understand its source dynamics and fault interactions, we conduct the first 3D high-resolution spontaneous dynamic rupture simulations of an induced earthquake. We account [...]
Crop residue burning practices across north India inferred from household survey data: bridging gaps in satellite observations
Published: 2020-03-03
Subjects: Environmental Sciences, Physical Sciences and Mathematics
In north India, agricultural burning adversely affects local and regional air quality during the post-monsoon season (October to November), when the prevailing meteorology is favorable for smog and haze formation. Quantifying the contribution of smoke to air pollution in this region, however, is challenging. While the Moderate Resolution Imaging Spectroradiometer (MODIS), aboard NASA’s Terra and [...]
Effect of fault damage zones on long-term earthquake behavior on mature strike-slip faults
Published: 2020-03-03
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Mature strike-slip faults are usually surrounded by a narrow zone of damaged rocks characterized by low seismic wave velocities. Observations of earthquakes along such faults indicate that seismicity is highly concentrated within this fault damage zone. However, the long-term influence of the fault damage zone on complete earthquake cycles, i.e., years to centuries, is not well understood. We [...]
Pre-inversion normal fault geometry controls inversion style and magnitude, Farsund Basin, offshore southern Norway
Published: 2020-02-29
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Inversion may localise along pre-existing structures within the lithosphere, far from the plate boundaries along which the causal stress is greatest. Inversion style and magnitude is expressed in different ways, depending on the geometric and mechanical properties of the pre-existing structure. A three-dimensional approach is thus required to understand how inversion may be partitioned and [...]
Constraining mechanisms of quartz precipitation during silicification and chemical sedimentation in the in the ~2.7 Ga Abitibi Greenstone Belt, Canada
Published: 2020-03-03
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
Silica-rich Precambrian rocks often preserve geochemical information and microfossil remnants from the early biosphere. Because these rocks are such critical geochemical and paleontological archives, we need robust tools to identify the chemical and physical conditions under which siliceous Precambrian rocks form, and determine how such information links to the specific depositional environment. [...]
Slip on wavy frictional faults: is the 3rd dimension a sticking point?
Published: 2020-03-03
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
The formulation for the 3D triangular displacement discontinuity boundary element method with frictional constraints is described in detail. Its accuracy in comparison to analytical solutions is then quantified. We show how this can be used to approximate stress intensity factors at the crack tips. Using this method, we go on to quantify how slip is reduced on fault surfaces with topography, [...]
Critical fluid injection volumes for uncontrolled fracture ascent
Published: 2020-03-03
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Hydro-fracturing is a routine industrial technique whose safety depends on fractures remaining confined within the target rock volume. Both observations and theoretical models show that, if the fluid volume is larger than a critical value, pockets of fluid can propagate large distances in the Earths crust in a self-sustained, uncontrolled manner. Existing models for such critical volumes are [...]