Gravity Theory Measurement practices Corrections Interpretation

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Presentation transcript:

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

Worden Gravimeter

Inside the Worden

Closing the Loop

Elevation Corrections Free Air Correction Bouguer Correction

Gravity Corrections Drift Correction Free Air Correction (tobs-tbase) x drift rate Free Air Correction (hobs-hbase) * 0.3086 mgal/m Bouguer Correction (hobs-hbase) * 0.04193r mgal/m where r = density in gr/cc

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

Gravity Corrections (sample)