Test of the radar fracture mapping tool in a lake using a known target
A method to locate fractures adjacent to but not intersecting a wellbore would be a great aid to the geothermal industry. A prototype downhole radar probe was recently completed with the aim of locating fractures near a single wellbore. This probe, operating in the pulse mode with a bandwidth of 30 to 300 MHz, contains two identical directional antennas. As with any prototype instrumentation, extensive field work is required to completely understand the characteristics of the system. A first step in that understanding is to operate the instrument under known or controlled conditions. In this paper, a series of tests of the radar probe in a lake using a known target are reported. In the tests, signals reflected from the target were observed when the target was 5 ft and 9 ft from the probe; in the latter case the returned signal was greatly attenuated by the water. The measured 3 dB beamwidth of the system to the target was 70 degrees. Finally, the effect of target size was studied by moving the probe across the face of the target.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (USA)
- DOE Contract Number:
- AC04-76DP00789
- OSTI ID:
- 6267983
- Report Number(s):
- SAND-87-1571C; CONF-871024-11; ON: DE87012369
- Resource Relation:
- Conference: Annual meeting of the Geothermal Resources Council, Sparks, NV, USA, 12 Oct 1987; Other Information: Paper copy only, copy does not permit microfiche production
- Country of Publication:
- United States
- Language:
- English
Similar Records
A prototype radar fracture mapping system
Field test results of a borehole directional radar