A5069964049- Geophysical Methods and Applications
- Seismic Waves and Analysis
- Seismic Imaging and Inversion Techniques
- Geophysical and Geoelectrical Methods
- Soil Moisture and Remote Sensing
- Microwave Imaging and Scattering Analysis
- Soil Geostatistics and Mapping
- Underwater Acoustics Research
- Landslides and related hazards
- Sensor Technology and Measurement Systems
- Scientific Research and Discoveries
- Soil and Unsaturated Flow
- Non-Destructive Testing Techniques
- Geochemistry and Geologic Mapping
- Geological Modeling and Analysis
- Peatlands and Wetlands Ecology
- Geophysics and Gravity Measurements
- Magnetic and Electromagnetic Effects
- Remote Sensing in Agriculture
- earthquake and tectonic studies
- Climate change and permafrost
- Tree Root and Stability Studies
- Cryospheric studies and observations
- Geotechnical and Geomechanical Engineering
- Hydrology and Watershed Management Studies
Forschungszentrum Jülich
2014-2024
Sphere Institute
2015-2021
Ernst Ruska Centre
2018
New Chemical Syntheses Institute
2015-2016
University of Lausanne
2014
Max Planck Institute for Nuclear Physics
2014
ETH Zurich
2004-2010
University of Miami
2010
Board of the Swiss Federal Institutes of Technology
2010
Bucknell University
2010
Abstract Technological and methodological progress is essential to improve our understanding of fundamental processes in natural engineering sciences. In this paper, we will address the potential new technological advancements soil hydrology move forward water related across a broad range scales. We focus on made quantifying root uptake processes, subsurface lateral flow, deep drainage at field catchment scale, respectively. elaborate value establishing science‐driven network hydrological...
Core Ideas There has been tremendous progress in GPR as a tool for soil water content determination. Numerous studies have shown the potential of to detect and map SWC. We highlight new possibilities achievements acquisition processing strategies. Quantitative SWC detection hydrological parameter estimation are possible using GPR. encourages other communities embrace Tremendous made with respect ground penetrating radar (GPR) equipment, data acquisition, since establishment determination...
We have developed a new full-waveform groundpenetrating radar (GPR) multicomponent inversion scheme for imaging the shallow subsurface using arbitrary recording configurations. It yields significantly higher resolution images than conventional tomographic techniques based on first-arrival times and pulse amplitudes. The is formulated as nonlinear least squares problem in which misfit between observed modeled data minimized. modeling implemented by means of finite-difference time-domain...
Core Ideas We provide an overview of the TERENO-Rur hydrological observatory. present information on general physical characteristics Rur catchment. Ongoing interdisciplinary research aims to advance understanding complex processes. observatory, which is main observational platform TERENO (TERrestrial ENvironmental Observatories) Eifel/Lower Rhine Valley Observatory. The catchment area exhibits distinct gradients in altitude, climate, land use, soil properties, and geology. Eifel National...
Abstract Electromagnetic induction (EMI) systems measure the soil apparent electrical conductivity (ECa), which is related to water content, texture, and salinity changes. Large‐scale EMI measurements often show relevant areal ECa patterns, but only few researchers have attempted resolve vertical changes in that principle can be obtained using multiconfiguration devices. In this work, we used determine lateral distribution of at field scale beyond. Processed data for six coil configurations...
Conventional ray-based techniques for analyzing common-midpoint (CMP) ground-penetrating radar (GPR) data use part of the measured and simplified approximations reality to return qualitative results with limited spatial resolution. Whereas these methods can give reliable values permittivity subsurface by employing only phase information, far-field used estimate conductivity ground are not valid near-surface on-ground GPR, such that estimated representative area investigation. Full-waveform...
Abstract Most activities of humankind take place in the transition zone between four compartments terrestrial system: unconfined aquifer, including unsaturated zone; surface water; vegetation; and atmosphere. The mass, momentum, heat energy fluxes these drive their mutual state evolution. Improved understanding processes that is important for climate projections, weather prediction, flood forecasting, water soil resources management, agriculture, quality control. different transport...
ABSTRACT Cross‐hole radar tomography is a useful tool for mapping shallow subsurface electrical properties viz. dielectric permittivity and conductivity. Common practice to invert cross‐hole data with ray‐based tomographic algorithms using first arrival traveltimes cycle amplitudes. However, the resolution of conventional standard inversion schemes ground‐penetrating (GPR) limited because only fraction information contained in used. The can be improved significantly by full‐waveform that...
Reliable high-resolution 3-D characterization of aquifers helps to improve our understanding flow and transport processes when small-scale structures have a strong influence. Crosshole ground penetrating radar (GPR) is powerful tool for characterizing due the method's sensitivity porosity soil water content. Recently, novel GPR full-waveform inversion algorithm was introduced, which here applied used by inverting six crosshole cross-sections collected between four wells arranged in square...
Heterogeneous small-scale high-contrast layers and spatial variabilities of soil properties can have a large impact on flow transport processes in the critical zone. Because their characterization is difficult critical, high-resolution methods are required. Standard ray-based approaches for imaging subsurface consider only small amount measured data suffer from limited resolution. In contrast, full-waveform inversion (FWI) considers full information content could yield higher resolution...
Core Ideas Horizontal straight holes for rhizotube installation were bored by a homemade system. Dynamics of root growth and soil moisture could be described rhizotron facilities. Soil monitored TDR GPR approaches in Minimally invasive monitoring development states (soil moisture, temperature) undisturbed soils during crop growing cycle is challenging task. Minirhizotron (MR) tubes offer the possibility to view situ with time. Two MR facilities constructed two different soils, stony vs....
Scalar imaging algorithms originally developed for the processing of remote sensing measurements (e.g., synthetic‐aperture radar method) or seismic reflection data Gazdag phase‐shift are commonly used ground‐penetrating (GPR) data. Unfortunately, these do not account radiation characteristics GPR source and receiver antennas vectorial nature waves. We present a new multicomponent algorithm designed specifically vector electromagnetic‐wave propagation. It accounts all propagation effects,...
Pronounced dispersion of ground-penetrating radar (GPR) waves is observed at locations distinguished by thin surface layers high-permittivity material (e.g., water-saturated soil). The characteristics depend on the permittivity and thickness effective waveguide below it. We introduce a scheme for estimating values these parameters from dispersed transverse-electric (TE) transverse-magnetic (TM) GPR data that analogous to recently developed methods analyzing Rayleigh recorded multichannel...
Electromagnetic induction (EMI) measurements return an apparent electrical conductivity that represents a weighted average of the distribution over certain depth range. Different sensing depths are obtained for different orientations, coil offsets, and frequencies, which, in principle, can be used multi‐layer inversion. However, instrumental shifts, which often occur EMI data, prevent use quantitative Recently, new calibration method was developed uses resistivity tomography (ERT) inversion...
Ground-penetrating radar (GPR) uses the recording of electromagnetic waves and is increasingly applied for a wide range applications. Traditionally, main focus was on analysis medium permittivity since estimates conductivity using far-field approximation contain relatively large errors cannot be interpreted quantitatively. Recently, full-waveform inversion (FWI) scheme has been developed that able to reliably estimate values by analyzing reflected present in on-ground GPR data. It based...
[1] A major challenge in vadose zone hydrology is to obtain accurate information on the temporal changes of vertical soil water distribution and its feedback with atmosphere groundwater. A state art coupled hydrogeophysical inversion scheme applied evaluate hydraulic properties a synthetic model field southern Ontario based time-lapse monitoring dynamics surface ground-penetrating radar (GPR). Film flow was included hydrological account for noncapillary sandy medium during dry conditions....
High-contrast layers caused by porosity or clay content changes can have a dominant effect on hydraulic processes within an aquifer. These act as low-velocity waveguides for GPR waves. We used field example from hydrological test site in Switzerland to show that full-waveform inversion of crosshole signals could image subwavelength thickness waveguiding layer. exploited the full information data, whereas ray-based techniques are not able such thin waveguide because they only exploit...
Abstract Limited knowledge about the spatial distribution of aquifer properties typically constrains our ability to predict subsurface flow and transport. Here we investigate value using high resolution full‐waveform inversion cross‐borehole ground penetrating radar (GPR) data for characterization. By stitching together GPR tomograms from multiple adjacent crosshole planes, are able image, with a decimeter scale resolution, dielectric permittivity electrical conductivity an alluvial along...