Preprints
There are 6976 Preprints listed.
Aquifer deformation and active faulting in Salt Lake Valley, Utah, USA
Published: 2020-04-12
Subjects: Earth Sciences, Geophysics and Seismology, Hydrology, Physical Sciences and Mathematics
Aquifers and fault zones may interact through groundwater flow and stress redistribution, yet their spatiotemporal relationship remains enigmatic. Here we quantify changes in water storage and associated stress along the Wasatch Fault Zone in Salt Lake Valley, recently shaken by a M5.7 earthquake on March 18th, 2020. Ground deformation mapped by Sentinel-1 SAR imagery (2014-2019) reveals an [...]
Social as much as environmental: the drivers of tree biomass in smallholder forest landscape restoration programmes
Published: 2020-04-13
Subjects: Environmental Sciences, Life Sciences, Natural Resources and Conservation, Physical Sciences and Mathematics
A major challenge for forest landscape restoration initiatives is the lack of quantitative evidence on how social factors drive environmental outcomes. Here we conduct a transdisciplinary quantitative analysis of the environmental and social drivers of tree biomass accumulation across 639 smallholder farms restoring native tree species in Mexico, Uganda and Mozambique. We use environmental and [...]
Global heat uptake by inland waters
Published: 2020-04-12
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Heat uptake is a key variable for understanding the Earth system response to greenhouse gas forcing. Despite the importance of this heat budget, heat uptake by inland waters has so far not been quanti?ed. Here we use a unique combination of global-scale lake models, global hydrological models and Earth system models to quantify global heat up take by natural lakes, reservoirs and rivers. The [...]
Concepts of space, time and scale
Published: 2020-04-11
Subjects: Forest Sciences, Geographic Information Sciences, Geography, Life Sciences, Social and Behavioral Sciences
Concepts of space, time and scale as well as their underpinning theories are crucial for understanding geospatial data. Space can be defined as a boundless, three-dimensional (3D) extent in which objects and events occur and have relative position and direction. Space has been considered to be absolute, meaning that it exists permanently and independently regardless of any matter in space. [...]
Identification of Hydrologic Landscapes in Brazilian basins and its application as indicator of water yield and storage
Published: 2020-04-09
Subjects: Civil and Environmental Engineering, Engineering, Environmental Studies, Life Sciences, Other Civil and Environmental Engineering, Other Life Sciences, Social and Behavioral Sciences
This study aimed to use the Hydrologic Landscapes as environmental classification method in the Piracicaba, Capivari and Jundiaí river basins, validate and use it as an indicator of water yield and storage areas. The method comprises in the same Information Plan (IP) factors that interact with the hydrological cycle in its terrestrial phase. The state of São Paulo, where most of the area is [...]
Fault seal modelling – the influence of fluid properties on fault sealing capacity in hydrocarbon and CO2 systems
Published: 2020-04-12
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Fault seal analysis is a key part of understanding the hydrocarbon trapping mechanisms in the petroleum industry. Fault seal research has also been expanded to CO2-brine systems for the application to Carbon Capture and Storage (CCS). The wetting properties of rock-forming minerals in the presence of hydrocarbons or CO2 are a source of uncertainty in the calculations of capillary threshold [...]
A new approach to inferring basal drag and ice rheology in ice streams, with applications to West Antarctic ice streams
Published: 2020-04-12
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Drag at the bed and along the lateral margins are the primary forces resisting flow in outlet glaciers. Simultaneously inferring these parame- ters is challenging since basal drag and ice viscosity are coupled in the momen- tum balance, which governs ice flow. Here, we test the ability of adjoint-based inverse methods to infer the slipperiness coefficient in a power-law sliding law and the [...]
Image processing on meso-scale photographs of brittle shear zones
Published: 2022-02-11
Subjects: Physical Sciences and Mathematics
Study of structures and fabrics from different scales of observation is an indispensable first step in structural geology and other branches of geoscience. We process three selected images of brittle shear zones from quartzite, limestone and schist samples using various methods, steps and filters. Such exercises more effectively detect brittle planes when the planes are not too close-spaced and [...]
Forming a Mogi Doughnut in the years prior to and immediately before the the 2014 M8.1 Iquique, Northern Chile Earthquake
Published: 2020-04-15
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Asperities are patches where the fault surfaces stick until they break in earthquakes. Locating asperities and understanding their causes in subduction zones is challenging because they are generally located offshore. We use seismicity, inter- and co-seismic slip, and the residual gravity field to map the asperity responsible for the 2014 M8.1 Iquique Chile earthquake. Until two weeks before the [...]
A mixed $RT_0 - P_0$ Raviart-Thomas finite element implementation of Darcy Equation in GNU Octave
Published: 2020-04-14
Subjects: Applied Mathematics, Bioresource and Agricultural Engineering, Chemical Engineering, Computational Engineering, Earth Sciences, Engineering, Environmental Sciences, Hydrology, Numerical Analysis and Computation, Partial Differential Equations, Physical Sciences and Mathematics, Water Resource Management
In this paper we shall describe mixed formulations -differential and variational- of Darcys flow equation, an important model of elliptic problem. We describe * Galerkin method with finite dimensional spaces; * Local matrices and assembling; * Raviart-Thomas $RT_0 - P_0$ elements; * Edge basis and local matrices for $RT_0 - P_0$ FEM; * Model problem with corresponding local matrices, right hand [...]
Introduction to geoinformation science
Published: 2020-04-11
Subjects: Forest Sciences, Geographic Information Sciences, Geography, Life Sciences, Social and Behavioral Sciences
Here, we define a geoinformation system (GIS) as a system, which is designed to capture, store, manipulate, analyze, manage, and present geospatial data. In university education, we study geoinformation science that is the science underlying geographic concepts, applications, and systems. Geoinformation science is dedicated to advancing our understanding of geographic processes and spatial [...]
Seismic electric signals (SES) and earthquakes: A review of an updated VAN method and competing hypotheses for SES generation and earthquake triggering
Published: 2020-04-07
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Studies, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Planetary Geophysics and Seismology, Planetary Sciences, Social and Behavioral Sciences
Electromagnetic phenomena are sometimes associated with seismic events, but earthquake prediction using seismic electric signals (SES) has not been seriously considered since the early 1990s. There are several causes: (1) false alarms that have created panics in Greece, and (2) a strong critique of the Varotsos-Alexopoulos-Nomicos (VAN) method used there. An updated VAN method that includes time [...]
Turbidites, Topography and Tectonics: Evolution of submarine channel-lobe systems in the salt-influenced Kwanza Basin, offshore Angola
Published: 2020-04-07
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology
Understanding the evolution of submarine channel-lobe systems on salt-influenced slopes is challenging as systems react to seemingly subtle changes in sea-floor topography. The impact of large blocking structures on individual deep-water systems is well documented, but understanding of the spatio-temporal evolution of regionally extensive channel-lobe systems in areas containing modest salt [...]
Band ratio to band difference for Chl of oceanic waters: broke a self-imposed no-touch zone
Published: 2025-08-28
Subjects: Education, Physical Sciences and Mathematics
There are many empirical algorithms developed for the remote sensing of chlorophyll-a concentration (Chl) from ocean color measurements, with the blue-green band-ratio type of algorithms dominating these practices. During the phase of algorithm development, which is data-driven, generally the errors of remote sensing reflectance (Rrs) from satellites are ignored until Hu et al. (2012) developed a [...]
Individual tree detection and characterization using 3D remote sensing
Published: 2020-04-11
Subjects: Forest Sciences, Geographic Information Sciences, Geography, Life Sciences, Remote Sensing, Social and Behavioral Sciences
Here, we will cover individual tree detection and characterization using 3D remote sensing. Simply, it means that point clouds are collected over a forested area using airborne laser scanning (ALS) or created using photogrammetric image interpretation and further used to detect individual trees using different algorithms. After the tree detection, the attributes of interest are predicted for each [...]