Preprints
There are 4725 Preprints listed.
A deep-learning estimate of the decadal trends in the Southern Ocean carbon storage
Published: 2021-04-21
Subjects: Atmospheric Sciences, Biogeochemistry, Climate, Earth Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Uptake of atmospheric carbon by the ocean, especially at high latitudes, plays an important role in offsetting anthropogenic emissions. At the surface of the Southern Ocean south of 30◦S, the ocean carbon uptake, which had been weakening in 1990s, strengthened in the 2000s. However, sparseness of in-situ measurements in the interior make it difficult to compute changes in carbon storage below [...]
CRUSTAL ACCRETION AND CHAIN BUILDING OF AN INHERITED PASSIVE MARGIN: INSIGHTS FROM THE WESTERN SOUTHERN ALPS
Published: 2021-04-20
Subjects: Tectonics and Structure
Recently, the influence of lithospheric extension on later orogeny has gained increasing interest. We make use of own geological mapping, interpretations of seismic reflection profiles and deep geophysical data to build an area-balanced cross-section across a key area of the Western Southern Alps and to model a series of structural restorations from the end of Mesozoic rifting to present-day. The [...]
Water acceleration in a supraglacial channel predicts locations of step-pool sequence formation
Published: 2021-04-20
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Supraglacial channels constitute an important part of the glacial hydrological system, both by influencing surface energy exchange as well as routing meltwater to eventually feed en- and subglacial drainage systems. Subglacial systems have received considerable scientific interest, but specific studies of supraglacial channels are sparse. This limited scientific understanding represents a missing [...]
Integrated multi-proxy source-to-sink analysis of the Lower Cretaceous of the Essaouira-Agadir Basin.
Published: 2021-04-20
Subjects: Geology, Sedimentology
This study investigates the Provenance of the Barremian-Aptian fluvial clastics exposed in the Essaouira-Agadir Basin which bears an important potential in terms of offshore feeding of reservoir sands. Thin section petrography and SEM, heavy minerals analysis, and detrital zircon dating were conducted and integrated with a large dataset of published low-temperature thermochronology studies to [...]
The 2019-2020 Southwest Puerto Rico earthquake sequence: seismicity and faulting
Published: 2021-04-20
Subjects: Geophysics and Seismology, Tectonics and Structure
The 2019-2020 Southwest Puerto Rico earthquake sequence ruptured multiple faults with several moderate magnitude earthquakes. Here we investigate the seismotectonics of this fault system using high precision hypocenter relocation and inversion of the near-field strong motions of five largest events in the sequence (5.6≤Mw≤6.4) for kinematic rupture models. The Mw6.4 mainshock occurred on an NE [...]
The Mid-Lithospheric Discontinuity caused by channel flow in the cratonic lithosphere
Published: 2021-04-20
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Stable cratons with a thick (> 200 km) and cold lithosphere form rheologically strong plates that move atop a ductile asthenospheric mantle. Various types of seismic observations show the presence of a potentially rheologically weak zone at depths of ca. 80 – 150 km termed the Mid-Lithosphere Discontinuity (MLD). While various mechanisms may explain the MLD, the dynamic processes leading to the [...]
Ongoing tectonic subsidence in the Lesser Antilles subduction zone
Published: 2021-04-20
Subjects: Earth Sciences
Geological estimates of vertical motions in the central part of the Lesser Antilles show subsidence on timescales ranging from 125.000 to 100 years, which has been interpreted to be caused by interseismic locking along the subduction megathrust. However, horizontal GNSS velocities show that the Lesser Antilles subduction interface is currently building up little to no elastic strain. Here we [...]
Revision of thelodonts, acanthodians, conodonts, and the depositional environments in the Burgen outlier (Ludlow, Silurian) of Gotland, Sweden
Published: 2021-04-20
Subjects: Biodiversity, Earth Sciences, Ecology and Evolutionary Biology, Life Sciences, Physical Sciences and Mathematics
Ludfordian strata exposed in the Burgen outlier in eastern Gotland record a time of initial faunal recovery after a global environmental perturbation manifested in the Ludfordian Carbon Isotope Excursion (LCIE). Vertebrate microfossils in the collection of the late Lennart Jeppsson, hosted at the Swedish Museum of Natural History, hold the key to reconstruct the dynamics of faunal immigration and [...]
The Effect of Ti on Ca-pv and Mg-pv phase stability
Published: 2021-04-20
Subjects: Physical Sciences and Mathematics
Magnesium silicate perovskite in the form of bridgmanite (bdg) and Calcium silicate perovskite (Ca-pv) have similar chemical structures and may mix into a single perovskite phase in the lower mantle which would have profound effects on many seismic properties. While we have previously found that this is unlikely to occur in pure bdg and ca-pv in this paper we examine whether phase mixing can be [...]
Impact and rebound of near real-time United States fossil fuel carbon dioxide emissions from COVID-19 and large differences with global estimates
Published: 2021-04-20
Subjects: Social and Behavioral Sciences
The COVID-19 pandemic has altered energy use and greenhouse gas (GHG) emissions globally and continues to evolve in the U.S. as the politics of COVID-19 change. Here we report on a new near-real-time fuel consumption data-driven, week-resolved estimate of national U.S. fossil fuel carbon dioxide (FFCO2) emissions, Vulcan-NRT. We explore the impact and rebound from the COVID-19 pandemic in the US. [...]
Particulate PhozzyLogic Index for policy makers—an index for a more accurate and transparent identification of critical source areas
Published: 2021-04-20
Subjects: Environmental Sciences, Physical Sciences and Mathematics, Water Resource Management
This study presents an algorithm for the allocation of particulate phosphorus (PP) loads entering surface waters to their sources of origin, which is a basic requirement for the identification of critical PP source areas and in turn a cost-effective implementation of mitigation measures. Furthermore, it conducts a sensitivity analysis determining the impacts of storm drains, discharge frequencies [...]
Subdivide and Conquer: Adapting Non-manifold Subdivision Surfaces to Surface-Based Representation and Reconstruction of Complex Geological Structures
Published: 2021-04-20
Subjects: Earth Sciences, Geology, Mining Engineering
Methods from the field of Computer Graphics are the foundation for the representation of geological structures in the form of geological models. However, as many of these methods have been developed for other types of applications, some of the requirements for the representation of geological features may not be considered and the capacities and limitations of different algorithms are not always [...]
Reactivation Potential of Intraplate Faults in the Western Quebec Seismic Zone, Eastern Canada
Published: 2021-04-19
Subjects: Earth Sciences, Physical Sciences and Mathematics
The intraplate western Quebec seismic Zone (WQSZ) in eastern Canada experiences moderate seismicity that mainly results from reactivation of inherited structures under the present-day, NE-striking regional stress field and, possibly to a minor extent, through stress perturbations in response to glacio-isostatic adjustments. This work comprises the first numerical stress simulation-based study [...]
Comparison of Machine Learning Approaches for Tsunami Forecasting from Sparse Observations
Published: 2021-04-18
Subjects: Physical Sciences and Mathematics
We have explored various different machine learning (ML) approaches for forecasting tsunami amplitudes at a set of forecast points, based on hypothetical short-time observations at one or more observation points. As a case study, we chose an observation point near the entrance of the Strait of Juan de Fuca, and two forecast points in the Salish Sea, one in Discovery Bay and the other in Admiralty [...]
The effect of water and pressure on fabric development in olivine
Published: 2021-04-17
Subjects: Physical Sciences and Mathematics
Water has a very strong effect on both the strength and fabric development of forsterite but the mechanism of this effect is unclear. In the paper we use Density Functional Theory Peierls-Nabarro modelling to examine the effect of water on the Peierls stress of different forsterite slip systems. We find that water in Mg vacancies will weaken [100](010) slip and thus produce A fabrics while [...]