The Geosoft database has the following channels:

FLT          - flt
DATE         - date
X            - UTM Eastings  NAD 83 Zone 21N
Y            - UTM Northings NAD 83 Zone 21N
Z            - corrected GPS Z
FID          - fiducial
UTC_TIME     - time (s)
RAW_ALTR     - raw helicopter to surface distance -  radar altimeter (ft)
ALTR_M_F_LAG - lagged, filtered helicopter to surface distance - radar altimeter (m)
PRESSURE     - barometric pressure (kPa)
BALT         - corrected barometric altitude
DTM          - digital elevation model using radar altimeter; height above sea level(m)
DTM_LVL      - levelled digital elevation model; height above sea level(m)
DIURNAL_RAW  - raw diurnal field (nT)
DIURNAL_FILT - filtered diurnal field (nT)
DIURNAL_COR  - diurnal correction (nT)
MAG2U        - raw total magnetic field (nT) port
MAG2_C       - compensated total magnetic field (nT)
MAG2_C_F     - filtered, compensated magnetic field (nT)
MAG2C_LD     - diurnally corrected total magnetic field (nT)
MAG3U        - raw total magnetic field (nT) starboard
MAG3_C       - compensated total magnetic field (nT)
MAG3_C_F     - filtered, compensated magnetic field (nT)
MAG3C_LD     - diurnally corrected total magnetic field (nT)
MAGTF        - total field magnetics at 'centre' of airborne platform (nT)
MAGTF_LEV    - levelled magnetic field (nt)
LAT_NAD83    - latitude  (degrees N)
LONG_NAD83   - longitude (degrees W)
IGRF         - IGRF correction (nT) calculated at altitude of 215 m 
MAG_IGRF     - levelled residual magnetic field (nt)
TRANS_GRAD   - transverse horizontal gradient (nT/m)
PITCH        - raw pitch from Septentrio (degrees)
ROLL         - raw roll from Septentrio  (degrees)
YAW          - raw yaw from Septentrio   (degrees)
PITCH_CAL    - corrected pitch (degrees)
ROLL_CAL     - corrected roll  (degrees)
YAW_CAL      - corrected yaw   (degrees)
MAGGRADROT_LATERAL 		- attitude corrected transverse magnetic gradient using corrected pitch and roll (nT/m)
MAGGRADROT_LONGITUDINAL 	- attitude corrected longitudinal magnetic gradient using corrected pitch and roll (nT/m)
MAGGRADROT_VERTICAL 		- attitude corrected vertical magnetic gradient using corrected pitch and roll (nT/m)


The following grids (Geosoft R*4 binary format) are included with the database

07013_mag_igrf_bidirhg.grd	- bidirectional gradient enhanced grid of residual magnetics (nT)
07013_mag_1vd.grd		- first vertical derivative of 07013_mag_igrf_bidirhg.grd (nT/m)