One Step Correction to Free-air Anomaly

Use the Moving Platform Gravity > One Step Correction to Free-Air Anomaly menu option (AGTOTCOR GX), to calculate the total corrected free-air anomaly in one step.

One Step Correction to Free-Air Anomaly dialog options

Latitude channel

The latitude channel name. The default name is "Latitude".

Script Parameter AGTOTCOR.LAT

Longitude channel

The Longitude channel name. The default name is "Longitude".

Script Parameter AGTOTCOR.LONG

Height channel

The elevation of the observation platform. For airborne surveys, this is the height above the sea level. The default will be set to "Height", if a channel by this name exists in the current database.

Script Parameter AGTOTCOR.HEIGHT

Hours to GMT (+ in West)

(optional)

This is the time difference between the time recorded in the survey database and GMT. This is a positive number in the Western hemisphere.

If this field is left blank, no tide correction is applied.

Script Parameter AGTOTCOR.GMT

Input absolute gravity channel

The absolute gravity channel name. The default name is "AbsGravity".

Script Parameter AGTOTCOR.INCH

Output Free-air anomaly channel

The total corrected free-air anomaly channel name. The default name is "Free-air".

Script Parameter AGTOTCOR.OUTCH

Application Notes

The Total Correction includes the Vertical Acceleration, Eötvös, Tide (optional), Latitude, and Free-air corrections:

Total Correction = Vertical Acceleration Correction - Free Air Correction - Eötvös Correction + Latitude Correction - Tide Correction (optional)

See Vertical Acceleration Correction, Eötvös Correction, Earth-Tide Correction, Latitude Correction and Free-Air Correction for the formulas.

To obtain the Free-air anomaly, the Total Correction is subtracted from measured values of absolute Gravity from the L+R meter in mGal (Gabs).