1. uSeismic Sonde In-Borehole Acoustic Compressional (P) & Shear (S) Velocity Measurements

2. Sonde Specifications Piezoelectric P wave transducer
Geophone S wave transducer
Wide range of independent gain control
Acquisition Period 5 msec to 80 msec
Adjustable spacing between energy source and receivers
Operates in fast hard rocks and slow formations
Dipole energy source to record normal and complementary S signals
Data acquisition hardware and software available
Data processing software available

3. Operating Conditions Sonde is suspended in the borehole, no clamping
Requires water\mud filled borehole
Source is built into the sonde, no surface source require
Can operate in PVC cased borehole

4. P Waveform Presentation
Near P wave is shown in red
Far P wave is shown in blue
X axis is in milliseconds

5. P Waveforms In Fast Formation

6. P Waveforms In Slow Formation

7. S Wave Acquisition Transmitter Operation
Transmitter fires first in Normal mode then Complementary mode.
Produces complementary signals at the S receivers
Aids in identification of S waves.

8. S Wave Presentation
Red and Orange signals are the near receiver Normal & Complementary signals.
Blue & light blue are far receiver Normal & Complementary signals.
X Axis is in milliseconds

9. S Waves in fast formation

10. S Waves In Slow Formation
Observe the normal and complementary nature of the signals.
Observe the presence of P waves at around 2 msec on the near receiver.

11. Processing Software Features
Imports the industry standard SEG2 files recorded during acquisition
Provides semblance correlation tools for determining time offset between near and far receivers.
Calculates velocities for both P & S signals
Exports results in several formats, including industry standard LAS format.

12. Sonde showing major components
The spacing between the transmitter and the receiver array can be adjusted by adding isolators of different lengths on top of the transmitter.

13. GeoVista uSeismic Sonde
Sonde Dimensions
Sonde diameter 50mm
Sonde weight 14 kgs
Sonde length 4.1 metres
This is the basic length without extra isolator sections installed.
Pressure rating 50 Bar as standard. Can be oil filled for higher pressure ratings.
GeoVista uSeismic Sonde

14. 11/10/2018
GeoVista 2014