The new datasets are generated from data stored in the Australian National Gravity Database; and include the Bouguer Gravity Anomaly Grid, Complete Bouguer Gravity Anomaly Grid and the Isostatic Residual Gravity Anomaly Grid.
The Complete Bouguer Gravity Anomaly Grid has had a terrain correction applied which removes the gravity effect of nearby topography variation.
Finally, the program subtracted the earth model gravity from the observed gravity to give the complete Bouguer gravity anomaly (CBOG) for each station.
The complete Bouguer gravity anomaly map (Figure 6) was generated from the data generated from the data processed in section 4.
In this research the simple Bouguer gravity anomaly
is used in comparisons.
High values of Bouguer gravity anomaly were encountered due to the presence of near-vertical faulting between areas of contrasting resistivity, and fault zones which may contain more or less highly contrasting density materials.
The Bouguer gravity anomaly map which one obtains from such a survey is actually a map of discrete potentials on the free surface, and any major singularity in the Bouguer gravity anomaly due to the presence of a perturbation will be due to the crossing from a "normal" into a "perturbed" area or vice versa.
Interpretation of the Bouguer gravity anomaly is the process of extracting information on the position and composition of a target mineral body in the ground.
The horizontal and the vertical derivatives of the Bouguer gravity anomaly map produced by a potential source form a Hilbert transform pair and define an analytic signal (Nabighian, 1972).
This survey, centered over a prominent pan (shallow depression) has shown the existence of a residual Bouguer gravity anomaly
measuring 200m by 300m, that may be indicative of the presence of a previously unknown kimberlite.
gamma]([OMEGA]) on the right-hand side of equation (5)is approximately equal to the simple Bouguer gravity anomaly
The regional correction was calculated from topography using Airy's model of crustal compensation and subtracted from the Bouguer gravity anomaly
, which then produced an isostatic residual gravity map of the study area.