Capacitively coupled EM sensors integrated in non-corrosive casings for longterm CSEM monitoring

We present a development of capacitively coupled EM sensors integrated in non-corrosive casings for permanent CSEM monitoring in boreholes. Capacitive sensors are required to detect low-frequency (diffusive-field) signals where voltage measurements fail and ammeters need to be used. The permanent installation in boreholes necessitates surface...

Estimating P-and S-Wave Velocities in Fluid Mud Using Seismic Interferometry

Fluid mud plays an important role in navigability in ports and waterways. Characterizing and monitoring the seismic properties of the fluid mud can help understand its geotechnical behavior. Estimation of the wave velocities in fluid mud with high accuracy and repeatability enables investigating the behavior of parameters like the yield stress...

Ultrasonic experiments for retrieval of layer-specific reflections inside fluid mud from ports with seismic interferometry

Knowledge about the characteristics of fluid mud in ports and waterways would allow safer navigating through fluid mud. The properties of the fluid mud determine the feasibility of navigating vessels through the fluid mud. Seismic waves have the potential to help characterize the fluid-mud layers, especially when both P- and S-waves are used....

Non-Intrusive Characterization and Monitoring of Fluid Mud: Laboratory Experiments with Seismic Techniques, Distributed Acoustic Sensing (DAS), and Distributed Temperature Sensing (DTS)

In ports and waterways, the bathymetry is regularly surveyed for updating navigation charts ensuring safe transport. In port areas with fluid-mud layers, most traditional surveying techniques are accurate but are intrusive and provide one-dimensional measurements limiting their application. Current non-intrusive surveying techniques are less...

Laboratory seismic measurements for layer-specific description of fluid mud and for linking seismic velocities to rheological properties

The velocities of the seismic waves propagating in the fluid-mud layer are governed by the rheological properties and density of the fluid mud. Performing seismic transmission measurements inside the fluid mud can give good estimates of the seismic velocities and, thus, of the rheological properties and density. Laboratory ultrasonic...

High-Resolution Ultrasonic Imaging of Artworks with Seismic Interferometry for Their Conservation and Restoration

Artworks are an inseparable part of the cultural heritage of societies and provide us with a unique look at cultural developments through time and space. For the best possible conservation, it is paramount to know the constituent materials, condition, and construction techniques of the objects (e.g. painting on wood, fresco, sculpture). Such...

Extraction of layer-specific seismic velocity in a porous medium through seismic interferometry applied to ultrasonic measurements of CO2 sequestration

Purpose: Time-lapse seismic monitoring constitutes the foundation for most monitoring programmes involving CO2 storage. When using time-lapse seismics, two major sources of uncertainty in the estimation of changes in the reservoir properties, like saturation and pressure, are the non-repeatability of the source positions and the difficulty to...

Seismic interferometry using ghost reflections applied to laboratory measurements for monitoring supercritical CO2 sequestration

The seismic method with active sources has proven to be a very valuable tool for CO2 sequestration monitoring. The seismic method can be used for extraction of reservoir quantities like saturation and pore pressure. But nonrepeatability in the positioning of the source and receiver during base and monitoring surveys can deteriorate the accuracy...

Laboratory monitoring of CO2 migration within brine-saturated reservoir rock though complex electrical impedance

We investigate the ability of complex electrical measurements to monitor the CO2 front propagation within brine-saturated reservoir rock. A laboratory facility has been developed to perform CO2-brine substitution experiments under reservoir conditions. In the present study, CO2 is injected into a brine-saturated core while the complex electrical...

Monitoring CO2 storage using seismic-interferometry ghost reflections

Time-lapse seismic monitoring is a fundamental part in most monitoring programmes involving CO2 storage. Even though the seismic method has proven its applicability for monitoring, there are two major causes of uncertainty in the estimation of changes in the reservoir properties: non-repeatability of the source positions and the difficulty in...

Laboratory monitoring of CO2 migration and phase transition using complex electrical conductivity

We explore a new monitoring technique for the CO2 front propagation and phase transition processes using complex electrical conductivity measurements. A laboratory facility has been built to conduct coreflood experiments under reservoir conditions. CO2 is injected in both dry and brine-saturated reservoir rock. The objectives of the study are to...

Medium characterization from interface-wave impedance and ellipticity using simultaneous displacement and pressure measurements

The interface-wave impedance and ellipticity are wave attributes that interrelate the full waveforms as observed in different components. For each of the fluid/elastic-solid interface waves, i.e., the pseudo-Rayleigh (pR) and Stoneley (St) waves, the impedance and ellipticity are found to have different functional dependencies on Young’s modulus...

Seismoelectric fluid/porous-medium interface response model and measurements

Coupled seismic and electromagnetic (EM) wave effects in fluid-saturated porous media are measured since decades. However, direct comparisons between theoretical seismoelectric wavefields and measurements are scarce. A seismoelectric full-waveform numerical model is developed, which predicts both the fluid pressure and the electric wavefields in...

Seismoelectric interface response: Experimental results and forward model

Understanding the seismoelectric interface response is important for developing seismoelectric field methods for oil exploration and environmental/engineering geophysics. The existing seismoelectric theory has never been validated systematically by controlled experiments. We have designed and developed an experimental setup in which acoustic-to...

Laboratory measurements and theoretical modeling of seismoelectric interface response and coseismic wave fields

A full-waveform seismoelectric numerical model incorporating the directivity pattern of a pressure source is developed. This model provides predictions of coseismic electric fields and the electromagnetic waves that originate from a fluid/porous-medium interface. An experimental setup in which coseismic electric fields and interface responses...