A5061252054- Seismic Waves and Analysis
- Seismic Imaging and Inversion Techniques
- Geophysics and Sensor Technology
- Seismology and Earthquake Studies
- Landslides and related hazards
- Cryospheric studies and observations
- Underwater Acoustics Research
- Geophysical Methods and Applications
- Structural Health Monitoring Techniques
- Advanced Fiber Optic Sensors
- Reservoir Engineering and Simulation Methods
- Planetary Science and Exploration
- Rock Mechanics and Modeling
- High-pressure geophysics and materials
- Underwater Vehicles and Communication Systems
- Winter Sports Injuries and Performance
- Inertial Sensor and Navigation
- Icing and De-icing Technologies
- Hydraulic Fracturing and Reservoir Analysis
- Arctic and Antarctic ice dynamics
- Evacuation and Crowd Dynamics
- Astro and Planetary Science
- Scientific Measurement and Uncertainty Evaluation
- Aeolian processes and effects
- Advanced Optical Sensing Technologies
ETH Zurich
2018-2025
Schlumberger (Norway)
2009-2019
Schlumberger (British Virgin Islands)
2014-2019
Schlumberger (United Kingdom)
2008-2018
Schlumberger (France)
2009
ABSTRACT With the potential of high temporal and spatial sampling capability utilizing existing fiber-optic infrastructure, distributed acoustic sensing (DAS) is in process revolutionizing geophysical ground-motion measurements, especially remote urban areas, where conventional seismic networks may be difficult to deploy. Yet, for DAS become an established method, we must ensure that accurate amplitude phase information can obtained. Furthermore, as spreading into many different application...
Interest in measuring displacement gradients, such as rotation and strain, is growing many areas of geophysical research. This results an urgent demand for reliable field-deployable instruments these quantities. In order to further establish a high-quality standard strain measurements seismology, we organized comparative sensor test experiment that took place November 2019 at the Geophysical Observatory Ludwig-Maximilians University Munich Fürstenfeldbruck, Germany. More than 24 different...
Abstract Avalanches and other hazardous mass movements pose a danger to the population critical infrastructure in alpine areas. Hence, understanding continuously monitoring are crucial mitigate their risk. We propose use Distributed Acoustic Sensing (DAS) measure strain rate along fiber‐optic cable characterize ground deformation induced by avalanches. recorded 12 snow avalanches of various dimensions at Vallée de la Sionne test site Switzerland, utilizing existing DAS interrogation unit...
Slope instabilities represent a significant hazard to communities and infrastructure across various regions worldwide. Climate change resultant increasing severe precipitation events potentially raise the risk of failing mass movements. Therefore, fundamental understanding slope failure processes is vital for reducing risks. Established remote-sensing synthetic aperture radar technologies provide valuable data on surface movement landslides, but only limited information...
Avalanche forecasters mostly rely on human observations of avalanche activity, but these reports are typically incomplete during periods poor visibility, delayed, and not automated. Automated detection systems equipped with seismic sensors can improve monitoring efficiency, providing accurate data to support forecasting, regardless visibility weather conditions. Additionally, such could be implemented as early warning tools enhance safety measures in mountain regions. While have been widely...
Snow avalanches in alpine regions pose significant risks to people and infrastructure. To mitigate these risks, early warning systems based on seismic sensors can provide real-time data avalanche activity, crucial for forecasting. Additionally, forecasting risk management require a thorough understanding of processes. However, release mechanism dynamics are only partly understood due the multi-physics processes involved, spanning from dynamic crack propagation granular turbulent flow....
We present our efforts to integrate Distributed Acoustic Sensing (DAS) data into the real-time seismic monitoring workflows of Swiss Seismological Service (SED) and Bedretto Underground Laboratory for Geosciences Geoenergies (BedrettoLab). Spanning from regional national fluid injection experiments at BedrettoLab, we show how DAS can be used effectively across many orders magnitude in temporal, spatial amplitude resolution. Using temporary deployments Switzerland, have incorporated SeisComP,...
Rock slope toppling typically occurs in slopes with steep, deep-seated discontinuities and involves large unstable rock masses that may transform into catastrophic secondary failures. Understanding the long-term weakening processes of such remains challenging due to limited subsurface access lack continuous deformation monitoring under diverse external forcings. To address these limitations, this study implements a comprehensive, tunnel-based multi-parameter system zone intersected by first...
Abstract During February 2023, a total of 32 individual distributed acoustic sensing (DAS) systems acted jointly as global seismic monitoring network. The aim this Global DAS Month campaign was to coordinate diverse network organizations, instruments, and file formats gain knowledge move toward the next generation earthquake networks. campaign, 156 earthquakes magnitude 5 or larger were reported by U.S. Geological Survey contributors shared data for 60 min after each event’s origin time....
A novel acquisition and processing technique is described to derive surface-wave dispersion curves from seismic ambient noise. We have determined that the use of spatial gradients wavefield provides new opportunities for high-resolution near-surface characterization with minimal field effort. In contrast conventional active source data analysis spatially smoothed results large dense arrays receivers, our method local phase velocity information noise using only three closely spaced geophones....
SUMMARY We present a technique to automatically classify the wave type of seismic phases that are recorded on single six-component recording station (measuring both three components translational and rotational ground motion) at Earth’s surface. make use fact each leaves unique ’fingerprint’ in motion sensor (i.e. is for type). This fingerprint can be extracted by performing an eigenanalysis data covariance matrix, similar conventional three-component polarization analysis. To assign from...
Abstract Interior exploration using Seismic Investigations, Geodesy and Heat Transport's (InSight) seismometer package Experiment for Structure (SEIS) was placed on the surface of Mars at about 1.2 m distance from thermal properties instrument flow Physical Properties Package (HP 3 ) that includes a self‐hammering probe. Recording hammering noise with SEIS provided unique opportunity to estimate seismic wave velocities shallow regolith landing site. However, value studying signals only...
A 2D land seismic data acquisition method that combines measurements of the vertical component particle velocity and horizontal rotation rate wavefield is presented. It shown station spacing such a survey can be increased to beyond corresponding spatial Nyquist wavenumber. An algorithm described separate once-aliased from data. The separated used for interpolation. field experiment shows sensors directly measure at free surface, required gradient wavefield. synthetic set demonstrate...
ABSTRACT Optimized experimental design aims at reducing the cost of a seismic survey by identifying optimal locations and amounts sources receivers. While acquisition in context imaging applies criteria like fold, offset spatial sampling, different attributes such as sensitivity kernels are more relevant for full waveform inversion. An ideal measure to quantify goodness an relies on eigenvalue spectrum approximate Hessian matrix, but this technique is computationally too expensive practical...
The InSight mission is a geophysical aimed at better understanding the structure of Mars and other rocky planets solar system. To do so, lander accommodating two cameras, very sensitive seismometer, dynamic self-penetrating heat probe nicknamed mole were placed on surface by Instrument Deployment Arm (IDA). Besides data (which definitely enriched existing knowledge Mars), instruments significantly increased geological geotechnical characteristics material site. Small strain (elastic)...
Rotational components just below the free-surface can be estimated by differencing closely spaced vertical geophones. This is particularly convenient because dedicated rotational sensors do not yet have high sensitivity and robustness for commercial use in seismic industry. In this paper, we show that new data type contains highly desirable information about wavefield. For instance, they provide a direct measurement of ray parameter, or equivalently, apparent velocity vertically polarized...
Summary We further investigate the benefit of a novel ground-roll attenuation method using newly available measurements rotational components wavefield. This is based on adaptive subtraction as noise models. Field tests demonstrate that these models are significantly better than those provided by horizontal conventional 3C geophone data. Because technique applied locally at an individual receiver station, coherent performance independent spatial sampling, in contrast to multi-trace velocity...
We demonstrate the detectability of snow avalanches using Distributed Acoustic Sensing (DAS) with existing fiber-optic telecommunication cables. For this, during winter 2021/2022, we interrogated a 10 km long cable closely following avalanche prone Fluelapass road in Swiss Alps. In addition to other signals like traffic and earthquakes, DAS data contain clear recordings numerous avalanches, even though most them do not reach cable. Here present two examples that could be verified...
ABSTRACT We built a five‐component (5C) land seismic sensor that measures both the three‐component (3C) particle acceleration and two vertical gradients of horizontal wavefield through pair 3C microelectromechanical accelerometers. The is small cylindrical device planted vertically just below earth's surface. show acquisition processing 5C data has potential to replace conventional with analogue geophone groups by single sensors placed at same station interval when combined suitable aliased...
We present a novel acquisition and processing technique for crossline scattered noise attenuation. The process is based on the use of rotational data to provide model adaptively subtract it from data, while inline propagating removed using conventional array-based methods. Synthetic tests demonstrate effectiveness technique, with significant improvement thanks new type data. Data field test also offered by technique.
We have introduced a workflow that allows subsurface imaging using upcoming body-wave arrivals extracted from ambient-noise land seismic data. Rather than the conventional interferometry approach based on correlation, we developed deconvolution technique to extract earth response observed periodicity in traces. The consists of iteratively applying gapped spiking deconvolution, providing multiple-free images with higher resolution correlation. validated for zero-offset traces simple synthetic...
SUMMARY This paper deals with theoretical aspects of wavefield decomposition Ocean Bottom Cable (OBC) data in the τ –p domain, considering a horizontally layered medium. We present both acoustic and elastic procedures simple compatible way. Acoustic aims at estimating primary upgoing P just above ocean-bottom, whereas upgoingP S wavefields below ocean-bottom. Specific issues due to interference phenomena receiver level are considered. Our motivation is introduce two-step scheme called...
A novel acquisition and processing technique is described to derive surface-wave dispersion curves from seismic ambient noise. We show that the use of spatial gradients wavefield provides new opportunities for high-resolution near-surface characterization with minimal field effort. In contrast conventional active source data analysis spatially smoothed results large dense arrays receivers, our method local phase velocity information using only three closely spaced geo-phones. time-frequency...