The borehole source BISH-SH generates horizontally polarized shear waves (SH) and compressional waves (P). Teh seismic signals are highly repeatable. The source works in dry or water filled boreholes and can be used in vertical or horizontal boreholes. Energy released by the IPG5000 discharges through a system of electromagnectical coils adjacent to a copper plate. When the plate is rejected a mechanical impact to the borehole wall is generated. The borehole source is coupled to the borehole wall by pneumatic clamping system (inflatable bladder). The orientation of the source is controlled from surface by a torsionally stiff hose.
The basic seismic crosshole source equipment consists of the electric surge generator IPGS and the remote control unit RCU. To the surge generator various seismic sparker sources can be connected. Triggering of the seismic acquisition system is performed by the remote unit.
Generated wave types: SH/P
Signal frequencies: Up to 4 kHz (depending on geology and borehole distance)
Operational depth: Up to 100 m
Source length: 880 mm
Source diameter: 65 mm
Source weight: 8.5 kg
Cable weight per meter: 665 g
Borehole diameter: 75-100 mm (or larger if spacers are used)
Clamping system: Inflatable bladder
Orientation: Torsionally stiff hose
Depth indicator: Cable marking every 2m
Connector: To Impulse Generator IPG5000
Storage: On Drum