Installing the 3TB in a borehole
If you see a different error message, make sure that the streams are in the
correct order in the WaveView window. If you still have problems, you may
have selected too few data points for it to be confident about the orientation;
you should try again with a larger selection.
6. After a few seconds, the calculation should finish and three windows will
appear. (They may obscure each other.) The top window is a graph of
Coherence vs Angle
:
The two-stage algorithm rotates the N/S and E/W components of the sensor
being tested in small steps.It measures first the amplitude similarity, and
then the coherence between the virtual (rotated) N/S component and the
reference N/S component, for a number of rotation angles.
The error in the final calculation is around 2.5°.
The peak of the coherence curve (upper graph) therefore corresponds to the
angle of rotation which best matched the reference component. This angle is
shown in the title bar, together with an estimated error.
You should see a coherence curve which is smooth and symmetrical. If the
curve is distorted, either the surface data are too noisy or the data selection is
too short.
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Issue G - November 2019
