GEOSv is the unique borehole source specifically designed for crosshole seismic testing (CST). Provided with a fast-locking pneumatic system, it allows to generate polarized vertical shear waves. This device is fully in accordance with international standard ASTM D7400-08. The operation of the GEOSv source is provided by the Jack energy sources.
| System | |
| Diameter | 65 mm |
| Length | 654 mm |
| Waterproof | 200 m |
| Max air pressure | 25 bar |
| Air pipe connection | 6 mm |
| Max piston range | 21.5 mm |
| Connector | High voltage 7 pins |
| Mechanical features | |
| Case | Aluminium |
| Clamping pistons | 2 |
| Eleactronic features | |
| Power supply | Max 3000V 300J |
| Frequency bandwidth | 100-600 Hz |
Jack energy sources ensure the operation of sparker and electrodynamic sources used in geophysical surveys in boreholes by methods of crosshole seismic testing (CST), vertical seismic profiling (VSP), vertical seismoacoustic profiling (VSaP) and others. Jack design deploys a reliable thyristor key, that enables obtaining a really short high-voltage electric pulse. The energy source is operated from the ас system with 110 / 220 V voltage.
Borehole sparker Pulse is utilized to generate pressure waves in water-filled boreholes while performing the operations via crosshole seismic testing (CST) and vertical seismic profiling (VSP) methods. The operation of the Pulse source is provided by the Jack energy source.
Jack energy source generates a short high-voltage electric pulse of considerable energy, which ensures the formation of ionized high-pressure gas-vapor cavities on the electrode group of the Pulse sparker, placed in a container with salt water. With explosive expansion of the gas-vapor cavity, the pressure in it rapidly decreases, what leads to a precipitate drop in the temperature, vapor condensation and subsequent collapse of the cavity, what does not lead to parasitic pulsations. The design of the source provides easy replacement of wear electrode groups, what also allows to control the signature of the source by installing a group with a different number of electrodes.
The standard diameters of the containers are 36 / 60 / 80 mm, thus allowing operations in wells with diameters starting from 40 mm. It is important to understand that in order to provide a stable pulse of high energy and a significant operational life of the source, a sufficient volume of the container and the number of electrodes greater than 25 are necessary. The operating life of the radiator is 5000–50000 excitations and depends on the number of electrodes and the energy supplied to them.
Pulse sources are shipped on geophysical reels equipped with high-voltage slip rings. Thus, one does not need to disconnect the source from a energy source during operations of winding / unwinding the cable.
The borehole source SHock is utilized to generate pressure (P-) and shear waves of horizontal polarization (SH-waves) in wells while performing the operations through crosshole seismic testing (CST) and reverse vertical seismic profiling (RVSP) methods. The operation of the SHock source is provided by the Jack energy sources.
The source generates a shear wave through an asymmetric blow delivered into wall of the well. A rigid pneumo-electric line makes it easy to rotate the source in the borehole, providing generation of “right” and “left” blows. The SHock source allows excitation of a seismic signal in both water-filled and dry wells, which is not feasible for borehole sparkers.
SHock is supplied on a reel equipped with a high-voltage slip ring. Thus, one does not need to disconnect the energy source during operations of winding / unwinding the cable.
The borehole hydrophone array WellStreamer is designed for borehole seismic surveys at pressure (P) waves. The hydrophone modules utilize highly sensitive piezoceramic sensors with preamplifiers. The default number of modules on the cable is 24, but it can vary from 1 to 48. The standard interval between pressure sensors is 1 m and the total length of the seismic array can reach 200 m or more.
The hydrophone array can be supplied on a reel with slip ring, which allows to leave the equipment plugged into it while winding and unwinding the cable.
The borehole seismic array with three-component clamping geophone modules GStreamer is designed for multiwave crosshole seismic testing and VSP. The number of modules on the cable can vary from 1 to 8. The interval between modules is determined by the customer.
Three normally oriented geophones with a natural frequency of 12.5 Hz are deployed in each module. The module clamping is achieved by a semi-active spring system with the possibility of remote snapping in the well. The load for the lowering the cable into borehole is not required.
The use of array with clamping modules along with borehole source of SH- waves SHock and Jack energy source allows multiwave observations with registration of SH- and P- waves at distances between wells up to 30 m.
The geophone array can be supplied on a reel with slip ring, which allows to leave the equipment plugged into it while winding and unwinding the cable.
The new inclinometer probe INCLIS DH, designed by SolGeo, allows to perform a 3D borehole deviation survey it is equipped with 3 magnetometric and an 3 accelerometric sensors. In case of iron casing which makes impossible the right working of the magnetometric sensors, the system is provided with a set of aluminium rod that allows to drive the probe inside the BH. INCLIS-DH is connected to the PC trough a USB Junction box which provides the power supply and the data transfer.
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