Profile Reversing


Profile, cruise POL7004 on the Juan de Fuca ridge. The scale is by longitude; the cruise sailed along a parallel from west to east.

The ridge may or may not be easy to pick out.

Enlarge image.
  • Export the profile to Paint.
  • Enlarge the overall canvas in Paint so you can put a second profile below it.  You may also want to add white space on either side of the profile, so you can move the reversed profile back and forth.
  • To get the reversed profile:
    • Reverse the x axis on the profile, on the right click, modify graph form.
    • Or
      • Export a second version of the profile below the first.
      • Perform a flip horizontal on one profile.  This gives a mirror image of the profile, and in geology legend, the accidental creation of a mirrored profile by looking at a clear overlay  from the back led to recognition of the symmetrical anomalies.
  • Select the reversed profile, and move it to locate the best match.

    Enlarge image.

Best match, with matching anomalies marked. 

  • Ridge crest is at -130.25, and is Anomaly 1.  It will often not be perfectly symmetrical.
  • Jaramillo event--half the magnitude for the ridge, and very short.
  • Anomaly 2
  • Anaomaly 2A (2 peaks, one is missing here)
  • Anomaly 3 (2 peaks marked, 2 more on east side only)

Enlarge image.

Marine magnetic profile interpretation. Includes time scale and anomaly names.

last revised 10/7/2015