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