Channel:Code Orthogonal Orientation Guidelines

Channel:Code Orthogonal Orientation Guidelines

From the SEED 2.4 (August 2012) Manual, Appendix A

Azimuth: degrees from north, clockwise.
Dip: degrees from horizontal.

The azimuth and dip describe the direction of an instrument's sensitive axis (if applicable). Motion in the same direction as this axis is positive. If instruments are reversed in the field, reverse the dip/azimuth fields. Data collection centers and data management centers should never actually modify the data, but report on its orientation.

Orthogonal Orientations

N — Dip 0, Azimuth 0 degrees (Reversed: Dip 0, Azimuth 180 degrees).
E — Dip 0, Azimuth 90 degrees (Reversed: Dip 0, Azimuth 270 degrees).
Z — Dip -90, Azimuth 0 degrees (Reversed: Dip 90, Azimuth 0 degrees).

If orthogonal instrument orientations are not within a 5 degree tolerance of N,E,Z, use non-traditional orthogonal orientations.

Non-traditional Orthogonal Orientations

1 — Channel Azimuth is greater than 5 degrees from north (Reversed: south).
2 — Channel Azimuth is greater than 5 degrees from east (Reversed: west).
3 — Channel Dip is greater than 5 degrees from vertical.

[2018-08-02]