This article will describe about Magnetic Declination and Grid Convergent and how to use them for directional drilling purposes.
Magnetic Declination
In the azimuth reference, three North references are Magnetic North, True North and Grid North (Figure 1). Since these 3 North references are not the same direction; therefore, it must be a correction in order to convert any Azimuth in the same reference. Two main concepts, which are magnetic declination and grid convergent, are used to AZI from the magnetic tool to the AZI referencing to the Grid North.
Figure 1 – True North, Magnetic North and Grid North
