Reduce to Pole or Equator

System

This discussion was created from comments split from: Welcome to the Oasis montaj Essentials Course Forum.

PhanVietHung

In the tool Magmap have filter design Reduce to Magnetic Equator and Reduce to Magnetic Pole, I want to ask: When do we used filter Reduce to Magnetic Equator and when do used filter Reduce to Magnetic Pole? And in Viet Nam should ude the filter?

BeckyBodger

Hi Quy,

Reduced to Magnetic Equator is generally used in areas of low magnetic latitudes. Please have a look at the Application notes in the help for Reduce to Magnetic Equator and Pole for more information:

https://my.geosoft.com/supportcentre#/help/oasismontaj-gxs-fft2con_rede.htm.
https://my.geosoft.com/supportcentre#/help/oasismontaj-extensions-fft2con_redp.htm

It's my understanding that you can use Reduce to Magnetic Pole for low latitudes, you would simply increase the Amplitude Correction the closer you get to the equator. However, this could result in artefacts perpendicular to your declination, or under-correcting the amplitudes of features along the declination direction. There's not often a single solution, you may want to try both Reduce to Magnetic Pole and Equator and compare the results.