Preprints
There are 6976 Preprints listed.
Cretaceous tectonics and gold mineralisation in the Otago Schist, New Zealand
Published: 2019-03-01
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
This paper provides a regional-scale background for understanding gold-mineralising processes in the Otago Schist during the Cretaceous. At this time the schist belt was in the latter stages of formation as an accretionary complex with 2000 km strike length on the Pacific margin of Gondwana. The Otago Schist is interpreted as an exhumed accretionary wedge of structurally stacked clastic [...]
Regional geological framework of New Zealands mineral deposits
Published: 2019-03-01
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
New Zealand is the emergent part of a 4.9 Mkm2, mainly submerged continent in the SW Pacific Ocean that was formerly part of the Gondwana supercontinent. The geology can be described in terms of two main Cambrian-Early Cretaceous basement units (Western and Eastern provinces) and a Late Cretaceous-Holocene sedimentary and volcanic cover (Zealandia Megasequence and Rūaumoko Volcanics). New Zealand [...]
The 2018-2019 seismo-volcanic crisis east of Mayotte, Comoros islands: seismicity and ground deformation markers of an exceptional submarine eruption
Published: 2019-03-01
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Volcanology
On May 10th, 2018, an unprecedented long and intense seismic crisis started offshore, east of Mayotte, the easternmost of the Comoros volcanic islands. The population felt hundreds of events. Over the course of one year, 32 earthquakes with magnitude greater than 5 occurred, including the largest event ever recorded in the Comoros (Mw = 5.9 on May 15th, 2018). Earthquakes are clustered in space [...]
Diagnosing spatial biases and uncertainties in global fire emissions inventories: Indonesia as regional case study
Published: 2019-02-28
Subjects: Environmental Monitoring, Environmental Sciences, Physical Sciences and Mathematics
Models of atmospheric composition rely on fire emissions inventories to reconstruct and project impacts of biomass burning on air quality, public health, climate, ecosystem dynamics, and land-atmosphere exchanges. Many such global inventories use satellite measurements of active fires and/or burned area from the Moderate Resolution Imaging Spectroradiometer (MODIS). However, differences across [...]
New insights on lake sediment DNA from the catchment: importance of taphonomic and analytical issues on the record quality
Published: 2019-02-27
Subjects: Earth Sciences, Ecology and Evolutionary Biology, Geochemistry, Geology, Life Sciences, Physical Sciences and Mathematics, Sedimentology, Soil Science, Terrestrial and Aquatic Ecology
Over the last decade, an increasing number of studies have used lake sediment DNA to trace past landscape changes, agricultural activities or human presence. However, the processes responsible for lake sediment formation might affect DNA archiving via taphonomic and analytical processes. It is crucial to understand these processes to ensure reliable interpretations for “palaeo” studies. Here, we [...]
Core Formation and Geophysical Properties of Mars
Published: 2019-02-25
Subjects: Earth Sciences, Geochemistry, Mineral Physics, Physical Sciences and Mathematics, Planetary Geophysics and Seismology, Planetary Sciences
The chemical and physical properties of the interiors of terrestrial planets are largely determined during their formation and differentiation. Modeling a planet’s formation provides important insights into the properties of its core and mantle, and conversely, knowledge of those properties may constrain formational narratives. Here, we present a multi-stage model of Martian core formation in [...]
Dynamics of the lithosphere and upper mantle in light of seismic anisotropy
Published: 2019-02-23
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Seismic anisotropy records continental dynamics in the crust and convective deformation in the mantle. Deciphering this archive holds huge promise for our understanding of the thermo-chemical evolution of our planet, but doing so is complicated by incomplete imaging and non-unique interpretations. Here, we focus on the upper mantle and review seismological and laboratory constraints as well as [...]
Structural and geodynamic modelling of the influence of granite bodies during lithospheric extension: application to the Carboniferous basins of northern England
Published: 2019-02-22
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Intra-basinal highs within classic ‘block and basin’ style tectonic frameworks, in areas such as northern England, are underpinned by large granite bodies. This is widely believed to relate to the relative ‘rigidity’ and ‘buoyancy’ of granite in relation to accommodating basement. It has been suggested that during periods of tectonic extension, normal faulting around the peripheral regions of [...]
Human-induced fire regime shifts during 19th century industrialization: a robust fire regime reconstruction using northern Polish lake sediments
Published: 2019-02-22
Subjects: Biogeochemistry, Earth Sciences, Environmental Sciences, Other Earth Sciences, Physical Sciences and Mathematics
Fire regime shifts are driven by climate and natural vegetation changes, but can be strongly affected by human land management. Yet, it is poorly known how exactly humans have influenced fire regimes prior to active wildfire suppression. Among the last 250 years, the human contribution to the global increase in fire occurrence during the mid-19th century is especially unclear, as data sources are [...]
Technical note on the multi-GNSS, multi-frequency and near real-time ionospheric TEC monitoring system for South America
Published: 2019-02-21
Subjects: Atmospheric Sciences, Earth Sciences, Geophysics and Seismology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Development of regional services able to provide ionospheric total electron content (TEC) maps with a high spatial resolution, and in near real-time, are of high importance for applications and the research community. We provide here the methodologies, and a preliminary assessment, of such a system. The system relies on the public Global Navigational Satellite Systems (GNSS) infrastructure in [...]
Opportunities for Classes of Geography in the High School: the Use of ’CORINE’ Project Data, Satellite Images and IDRISI GIS for Geovisualization
Published: 2019-02-13
Subjects: Adult and Continuing Education, Education, Educational Methods, Environmental Education, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Environmental Studies, Geographic Information Sciences, Geography, Higher Education, Human Geography, Natural Resources Management and Policy, Nature and Society Relations, Physical and Environmental Geography, Physical Sciences and Mathematics, Remote Sensing, Science and Mathematics Education, Social and Behavioral Sciences, Spatial Science, Sustainability
Presented work illustrates application of the GIS based processing of various geographic data: satellite images and CORINE (Coordination of Information on the Environment) layers at the lessons of geography in the high schools and universities. The research illustrates GIS application for understanding, visualizing and modeling landscapes of the Earth. Practically, the work aims to demonstrate [...]
Long Range Correlation in Redox Potential Fluctuations Signals Energetic Efficiency of Bacterial Fe(II) Oxidation
Published: 2019-02-21
Subjects: Biogeochemistry, Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Differentiating biotic and abiotic processes in nature remains a persistent challenge, specifically in evaluating microbial contributions to geochemical processes through time. Building on previous work reporting that biologically-influenced systems exhibit stronger long-range correlation than abiotic systems, this study evaluated the relationship between long-range correlation of redox [...]
Deep Learning Application for 4D Pressure Saturation Inversion Compared to Bayesian Inversion on North Sea Data
Published: 2019-02-21
Subjects: Applied Statistics, Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Statistics and Probability
In this work we present a deep neural network inversion on map-based 4D seismic data for pressure and saturation. We present a novel neural network architecture that trains on synthetic data and provides insights into observed field seismic. The network explicitly includes AVO gradient calculation within the network as physical knowledge to stabilize pressure and saturation changes separation. [...]
geomIO: an open-source MATLAB toolbox to create the initial configuration of 2D/3D thermo-mechanical simulations from 2D vector drawings
Published: 2019-02-21
Subjects: Earth Sciences, Physical Sciences and Mathematics
Creating the initial geometry and temperature configuration of 3D numerical simulations is a challenging task. Professional tools are expensive. They often have a steep learning curve and do mostly not interface with the numerical simulation software used by the geodynamics and tectonics academic community. There, we developed geomIO (geometry Input/Output), a MATLAB toolbox to create the initial [...]
Reconstruction of Cloud Vertical Structure with a Generative Adversarial Network
Published: 2019-02-19
Subjects: Artificial Intelligence and Robotics, Atmospheric Sciences, Computer Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
We demonstrate the feasibility of solving atmospheric remote sensing problems with machine learning using conditional generative adversarial networks (CGANs), implemented using convolutional neural networks (CNNs). We apply the CGAN to generating two-dimensional cloud vertical structures that would be observed by the CloudSat satellite-based radar, using only the collocated Moderate-Resolution [...]