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Measured the sonic azimuths to be 265 deg magnetic. (Note the declination on the compass was actually ~ 1 degree east, not zero.)
Magnetic declination is about 2 deg W here, so the sonic azimuths are about 263 deg true.
...
Measured the sonic azimuths to be 265 deg magnetic. (Note the declination on the compass was actually ~ 1 degree east, not zero.)
Magnetic declination is about 2 deg W here, so the sonic azimuths are about 263 deg true.