1. Gravity Theory Measurement practices Corrections Interpretation
Relative
Closed loops
Corrections
Drift
Free Air
Bouguer
Terrain
Interpretation
Modeling

13. Worden Gravimeter

14. Inside the Worden

18. Closing the Loop

19. Elevation Corrections
Free Air Correction
Bouguer Correction

20. Gravity Corrections Drift Correction Free Air Correction
(tobs-tbase) x drift rate
Free Air Correction
(hobs-hbase) * mgal/m
Bouguer Correction
(hobs-hbase) * r mgal/m
where r = density in gr/cc

21. Gravity Anomalies Free Air Anomaly
Dgfa = (gobs-gbase) – (drift corr) + (fa corr)
Bouguer Anomaly
Dgb = Dgfa –(bouguer correction)

22. Gravity Corrections (sample)