Airborne Gravity 2010 - Geoscience Australia

Airborne Gravity 2010
Figure 1. Vector component representation of a tensor.
Tensor Inversion
The example used here to demonstrate the power of a tensor consists of a circular pipe of 30 m
radius, situated 60 m from the closest line. The full survey consists of north-south survey lines 200 m
apart (Figure 2).
Figure 2. Survey design for the synthetic example showing pipe location (magenta) and survey
lines (orange).
The full tensor was calculated along each survey line using ModelVision forward modelling software
(Encom ModelVision, n.d.). An inversion was initiated using ModelVision joint inversion software using
only data from the middle third of the central closest line with the starting model offset 200 m northeast
of the exact solution (Figure 3). Even though the correct location was away from the line, the inversion
correctly positioned the solution over the source model (see Figure 4).
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