Results 131 to 140 of about 603 (176)

Subsurface fracture measurement with polarimetric borehole radar

IEEE Transactions on Geoscience and Remote Sensing, 1999
A full-polarimetric borehole radar system is presented with combinations of dipole antennas and axial slot antennas and is applied to subsurface fracture measurement. First, to determine a scattering matrix from measurements with antennas having different antenna transfer functions between orthogonal polarizations, the authors present an antenna ...
Takashi Miwa, Motoyuki Sato, Hiroaki Niitsuma   +2 more
openaire   +1 more source

Borehole radar measurements

International Symposium on Antennas and Propagation Society, Merging Technologies for the 90's, 1990
An analysis of transient responses between dipole antennas set in parallel boreholes is presented in order to obtain a basic understanding of the operation of borehole radars. The theoretical response was derived, and the results are found to agree well with measured data in a salt deposit.
openaire   +1 more source

Estimation of a buried pipe location by borehole radar

Proceedings. 2005 IEEE International Geoscience and Remote Sensing Symposium, 2005. IGARSS '05., 2005
A new parametric inversion technique to estimate a buried pipe location was developed for borehole radar cross-hole measurements. This technique evaluates the shapes of the approximated and measured arrival time curves instead of the first arrival time itself or wavefield in conventional inversion or tomographic techniques. In this study, we propose an
Kazunori Takahashi, Motoyuki Sato
openaire   +1 more source

Electromagnetic logging technique based on borehole radar

IEEE Transactions on Geoscience and Remote Sensing, 2002
An electromagnetic logging technique based on borehole radar is introduced in this paper. The tool consists of one transmitter and two receivers, which can be used to cancel the effect of the antenna characteristics by taking the ratio of two receiver signals. Since receiver signals measured in the time domain can be converted into the frequency domain
Sixin Liu, Motoyuki Sato
openaire   +1 more source

Multifold borehole radar acquisition and processing

Geophysical Prospecting, 1999
The multifold acquisition principle was applied to a borehole radar survey, performed in a granitic site (Grimsel Test Site, Switzerland). Two multifold coverage acquisitions (40‐fold and 20‐fold) were carried out in a subhorizontal borehole. Instrumental drifts (transmission time and sampling frequency fluctuations) were corrected in order to remove ...
Fabrice Hollender, Sylvie Tillard, Laurent Corin   +2 more
openaire   +1 more source

RADAR DETECTION OF BOREHOLES IN ADVANCE OF MINING*

Geophysical Prospecting, 1978
AbstractBoreholes present a potential hazard to mining in rock salt mines. The only rock salt mine in England was almost lost when they mined into an unknown borehole open to an aquifer. Rock salt is a good transmitter of VHF radar waves, so a good method of detecting boreholes is by using radar probing.
P. J. TARANTOLO, R. R. UNTERBERGER
openaire   +1 more source

Ultra-Wideband Polarimetric Borehole Radar

2005
Stepped-frequency ultra-wide-band polarimetric borehole radar system was developed and tested for subsurface fracture characterization. The radar was tested for subsurface fracture characterization. Scattering matrix of subsurface fractures can be estimated by using the radar system and examples of polarimetric signature were shown.
Motoyuki Sato, Sixin Liu
openaire   +1 more source

Borehole-radar exploration in a coal seam

Geophysics, 1977
Abstract The experimental use of "geologic radar" to explore through coal from mined passages underground has already been reported elsewhere (Cook, 1973, 1974). Low-resolution borehole radar work in salt, a much more favorable medium, has also been reported (Holzer et al., 1972). The purpose of this paper is to report the first known
openaire   +1 more source

Monitoring engineered remediation with borehole radar

The Leading Edge, 2007
The success of engineered remediation is predicated on correct emplacement of either amendments (e.g., vegetable-oil emulsion, lactate, molasses, etc.) or permeable reactive barriers (e.g., vegetable oil, zero-valent iron, etc.) to enhance microbial or geochemical breakdown of contaminants and treat contaminants.
John W. Lane, Frederick D. Day-Lewis, Peter K. Joesten   +2 more
openaire   +1 more source

Recent ARL borehole radar experiments

SPIE Proceedings, 2006
The Microwave Sensors Branch of the Army Research Laboratory (ARL) recently evaluated the potential of a commercially available borehole radar system for an underground target detection application. We used this ground-penetrating system, which is capable of operation at either 100 or 250 MHz, to conduct experiments at a locally constructed test site ...
Kenneth Ranney, Brian Stanton, Anders Sullivan, Traian Dogaru, Gregory Smith, Marc Ressler, David Wong, Lam Nguyen, Karl Kappra, Chi Tran, Getachew Kirose, John Costanza, Jeff Sichina   +12 more
openaire   +1 more source