The

The FORTRAN program GRS80.exe is a

1. Convert data from IAG 1930 to GRS80.

2. Convert data from GRS67 to GRS80.

3. Apply atmospheric correction.

4. Run options 1 and 3.

5. Run options 2 and 3.

6. Computation of free-air anomalies.

7. Computation of Bouguer anomalies.

8. Convert free-air anomalies to Bouguer anomalies.

9. Convert Bouguer anomalies to free-air anomalies.

This menu is displayed when the program is executed. We can select any option of this menu giving the corresponding number, after the following request:

Select the option (1,2,3,4,5,6,7,8 or 9):

Give the NEW values for rho and rhow:

Input-data file name:

Output-data file name:

These data files must be in the format: longitude (east degrees), latitude (north degrees) and gravity anomaly (mgal). The files must have a record like this by each gravity point. The gravity anomalies are converted from IAG 1930 to GRS80, by means of the formula (Torge, 1989):

in the above-presented formulas the notation is

Input-data file name:

Output-data file name:

These data files must be in the format: longitude (east degrees), latitude (north degrees) and gravity anomaly (mgal). The files must have a record like this by each gravity point. The gravity anomalies are converted from GRS67 to GRS80, by means of the formula (Torge, 1989):

Input-data file name:

Output-data file name:

The input-data file must be in the format: longitude (east degrees), latitude (north degrees), gravity anomaly (mgal) and height (m). The input-data file must have a record like this by each gravity point. The gravity anomalies are corrected by means of the formula (Kuroishi, 1995):

Input-data file name:

Output-data file name:

The input-data file must be in the format: longitude (east degrees), latitude (north degrees), gravity value (mgal) and height (m). The input-data file must have a record like this by each gravity point. The gravity anomalies are computed by means of the formula (Heiskanen and Moritz, 1967):

in the above-presented formulas h is the ellipsoidal height (m) and H is the orthometric height (m). The normal gravity (mgal) and the constants: a, m, f; are computed in the GRS80 system. The values of (a, m, f) are (Leick, 1995):

a = 6378137 m

m = 0.00344978600308

f =1/298.257222101

Input-data file name:

Output-data file name:

The input-data file must be in the format: longitude (east degrees), latitude (north degrees), gravity value (mgal) and height (m). The input-data file must have a record like this by each gravity point. The gravity anomalies in land are computed by means of the formula (Heiskanen and Moritz, 1967):

Input-data file name:

Output-data file name:

The input-data file must be in the format: longitude (east degrees), latitude (north degrees), free-air anomaly (mgal) and height (m). The input-data file must have a record like this by each gravity point.

Input-data file name:

Output-data file name:

The input-data file must be in the format: longitude (east degrees), latitude (north degrees), Bouguer anomaly (mgal) and height (m). The input-data file must have a record like this by each gravity point.

Heiskanen W. A. and Moritz H., 1967.

Kuroishi I., 1995.

Leick A., 1995.

Torge W., 1989.