Magnetic Units of Measure, in Brief

By default, GM-SYS Profile Modelling uses the Gaussian (cgs) system of units for magnetic terminology and quantities (susceptibility, magnetization, magnetic induction and magnetic field intensity). You can choose to display using International System (Le Système International d'Unités or SI) or µcgs units by selecting the appropriate option in the Display | Anomaly Units menu option.

Quantity	cgs	SI	GM‑SYS Usage
ΔB	gamma	nanotesla	Calculated and Observed Magnetic Anomalies
H (orB)	gamma (=nT)	A/m	Magnitude of Earth’s Magnetic Field
FI	degree		Inclination of Earth’s Magnetic Field
FD	degree		Declination of Earth’s Magnetic Field
Mr or Jr	emu/cc	A/m	Remanent Magnetization a
MI	degree		Inclination of Remanent Magnetization
MD	degree		Declination of Remanent Magnetization
or	dimensionless		Susceptibility b,c
			a Appears as "M" in displayed Block Parameters b Appears as "S" in displayed Block Parameters c Also referred to as "volume susceptibility"

To convert between SI units and cgs units (modified from Blakely, 1995). For example, divide magnetization expressed in A/m by 10³ to calculate the magnetization in gauss.

Refer to the Magnetic Conversion Factors topic for more detail.