Extracting mud invasion information using borehole radar - A numerical study

In hydrocarbon drilling, mud filtrate penetrates permeable formations and alters the pore fluid characteristics in the immediate vicinity of the borehole. Typically, the prevailing in situ pore fluids are displaced by the invading mud filtrate, which leads to gradually changing distributions of the fluid and electrical properties....

Fast 3D ground penetrating radar simulations for glaciers

Modeling ground penetrating radar (GPR) reflection data on glaciers with methods that require the discretization of the full subsurface domain is extremely computationally expensive because of the combination of a large domain size and the comparatively short wavelength of the signal. To address this issue, we build on and extend a previously...

Associating Borehole Radar Imaging with Petrophysical Properties for a Mud-Contaminated Reservoir

In the phase of oil drilling, mud filtrate penetrates into porous formations and alters the pore fluid properties. This complicates well logging exploration, and inevitably gives rise to shift in reservoir estimation. Logging engineers deem mud invasion a harm and attempt to eliminate its impact on logging data exploration. However, from our...

Theory for 1D GPR data inversion for a dissipative layered medium

We present a data driven method of full waveform inversion in one dimension. This means that the inversion is carried out as a sequence of processing steps. The first step is known as Marchenko redatuming. In this step we retrieve focusing functions from the measured data. In the second step we isolate the last event in the focusing function to...

Reservoir monitoring using borehole radars to improve oil recovery: Suggestions from 3D electromagnetic and fluid modeling

The recently developed smart well technology allows for sectionalized production control by means of downhole inflow control valves and monitoring devices. We consider borehole radars as permanently installed downhole sensors to monitor fluid evolution in reservoirs, and it provides the possibility to support a proactive control for smart...

Non-invasive estimation of moisture content in tuff bricks by GPR

Measuring water content in buildings of historical value requires non-invasive techniques to avoid the damage that sample taking or probe insertion may cause to the investigated walls. With this aim, a stepped frequency ground penetrating radar (GPR) system was tested to assess its applicability in moisture measurements of porous masonry...

Modeling of GPR data in a stack of VTI-layers with an analytical code

Coupling ground penetrating radar and fluid flow modeling for oilfield monitoring applications

The recent introduction of smart well technology allows for new geophysical monitoring opportunities. Smart wells, which allow zonal production control, combined with monitoring techniques capable of capturing the arrival of undesired fluids, have the potential to significantly increase the oil recovery. We consider borehole radar as a valuable...

Surface and borehole ground-penetrating-radar developments

During the past 80 years, ground-penetrating radar (GPR) has evolved from a skeptically received glacier sounder to a full multicomponent 3D volume-imaging and characterization device. The tool can be calibrated to allow for quantitative estimates of physical properties such as water content. Because of its high resolution, GPR is a valuable...

Interferometry by deconvolution of multicomponent multioffset GPR data

Interferometric techniques are now well known to retrieve data between two receivers by the cross correlation of the data recorded by these receivers. Cross-correlation methods for interferometry rely mostly on the assumption that the medium is loss free and that the sources are all around the receivers. A recently developed method introduced...

Uniqueness and stability analysis of hydrogeophysical inversion for time-lapse ground-penetrating radar estimates of shallow soil hydraulic properties

Precise measurement of soil hydraulic properties at field scales is one of the prerequisites to simulate subsurface flow and transport processes, which is crucial in many research and engineering areas. In our study, we numerically analyze uniqueness and stability for integrated hydrogeophysical inversion of time-lapse, off-ground ground...

Fast evaluation of zero?offset Green's function for layered media with application to ground?penetrating radar

We propose an efficient integration path for the fast evaluation of the three?dimensional spatial?domain Green's function for electromagnetic wave propagation in layered media for the particular case of zero?offset, source?receiver proximal ground?penetrating radar (GPR) applications. The integration path is deformed in the complex plane of the...

Closed loop GPR data inversion for soil hydraulic and electric property determination

We propose an integrated electromagnetic-hydrodynamic inverse modeling approach for identifying field-scale unsaturated soil hydraulic properties and electric profiles from off-ground time-lapse ground-penetrating radar data. Hydrodynamic modeling based on the one-dimensional Richards' equation with homogeneous soil hydraulic parameters is used...

Analysis of air-launched ground-penetrating radar techniques to measure the soil surface water content

We analyze the common surface reflection and full-wave inversion methods to retrieve the soil surface dielectric permittivity and correlated water content from air-launched ground-penetrating radar (GPR) measurements. In the full-wave approach, antenna effects are filtered out from the raw radar data in the frequency domain, and full-wave...

Report on ground-penetrating radar techniques for seawall asphalt pavement investigations

This report discusses possibilities of using radar technology in asphalt pavement investigations in several types of pavement. The main focus is on highly porous asphalt (OSA) and watertight asphalt concrete (WAB), as used in Dutch seawalls. The determinations of layer thickness as well as layer integrity are important goals. The asphalt...

A new integrated approach for characterizing the soil electromagnetic properties and detecting landmines using a hand-held vector network analyzer

The application of ground-penetrating radar (GPR) in humanitarian demining labors presents two major challenges: (1) the development of affordable and practical systems to detect metallic and non-metallic antipersonnel (AP) landmines under different conditions, and (2) the development of accurate soil characterization techniques to evaluate soil...

Effect of soil roughness on the inversion of off-ground monostatic GPR signal for noninvasive quantification of soil properties

We report on a laboratory experiment that investigates the effect of soil surface roughness on the identification of the soil electromagnetic properties from full-wave inversion of ground-penetrating radar (GPR) data in the frequency domain. The GPR system consists of an ultrawide band stepped-frequency continuous-wave radar combined with an off...