| Title | Test of the Radar Fracture Mapping Tool in a Lake Using a Known Target |
|---|---|
| Authors | Duda, Leonard E.; Hsi-Tien Chang; Uhl, James E.; Gabaldon, John |
| Year | 1987 |
| Conference | Geothermal Resources Council Transactions |
| Keywords | Exploration; Geochemistry; Geophysics; Fractures |
| Abstract | A method to located fractures adjacent to but not intersecting a wellbore would be a great aid to the geothermal industry. A prototype downhole radar probe was recently compiled 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. A with any prototype instrumentation, extensive fieldwork 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 the lake using a known target are reported. In the tests, signals reflected from the target t 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 measure 3 dB beam width of the system to the target was 70 degrees. Finally, the effect of the target size was studied by moving the probe across the face of the target. |