MALÅ Borehole Antenna for deeper survey
The MALÅ Borehole Antenna are often used for deep survey. The system can obtain information at greater depths which is not obtainable with surface GPR. With the use of fiber optic cables for communication, the system successfully surveyed down to the depths in excess of 2500m.
Survey Methods
Common measurement methods include single-hole reflection mode, cross-hole mode (tomography) and surface-to-borehole mode.
The area of investigation is a cylinder shaped volume around the borehole with a radius of 10 – 100 m (dependent on electrical properties of the media under investigation).
In reflection mode the transmitter and receiver are deployed in the same borehole. The antennas are dipoles and radiate and receive reflected signals omni-directionally.
Data is displayed in real time using the MALÅ GroundVision software.
When using this mode, it is recommended that user scans in at least three boreholes to determine the exact distance and bearing of the reflector.
Applications
The MALÅ Borehole Antenna System is recommended for applications including fracture characterization, foundation engineering/ studies, karst imaging, cavity and void detection, flow path analysis, localization of “lost” boreholes, delineation of ores, earth dam investigations, contamination transportation and more.
Accessories
A number of accessories are available for the MALÅ Borehole Antennas, including:
- Antenna separators
- Tripods
- Mechanical / digital depth encoders
- Electrical winches