Digital Downhole Geophone System

 

The Geovista Digital Borehole Geophone system includes a down the hole digital sonde and a compact digital interface unit at the surface. There is no requirement for a seismograph.

The sonde runs on a single conductor, on a standard logging winch. It includes a motorized clamping arm and three SM24 geophones arranged in an X-Y-Z pattern.

The clamping arms is motorised to work in a range of borehole diameters, to ensure adequate coupling with the seismic signal.

The geophones are non-gimbaled, 3axis devices, allowing for seismic energy to be measured in X and Y horizontal axes for shear S-wave arrivals, and in the vertical axis Z for compression P-wave arrivals.

The digital interface unit at the surface has inputs for the down the hole sonde, three surface geophones and the trigger from the hammer source.

Collected data is output to a PC via the USB port. The acquisition software allows for data viewing and stacking.

The generated SEG2 files can then be imported into most commercial seismic processing software.


Specifications:

 

Weight / length:                    15 kg / 1.69 m

Diameter :                            64mm

Clamping:                            Motorised Arm

Downhole Sensors:             X-Y-Z SM24 geophones

Surface Sensors:                3 geophones with simultaneous recording

Seismic Source:                  As per client requirements

Trigger:                                From hammer source

Data acquisition:                  Max. 5s record length / 14 bit resolution on a 500

microsecond sample interval.

Output file format:               SEG2

Oper. Press./Temp.            Max. 20 Mpa / 80ÂșC