Specifications

University of Pretoria etd – Combrinck, M (2006)
0.001
0.01
0.1
1
0 100 200 300 400 500 600
Depth [m]
Imaged Conductivity [S/m]
300 m Prism
300 m Plate
In f i ni te She e t
Figure 4-55: Comparison between imaged conductivities of a 0.2 S/m prism, 20 m thick plate
and infinite sheet of 20 m thickness at 150 m depth in a 0.02 S/m host rock. Both the plate and
prism have horizontal dimensions of 300 m.
Figure 4-55 shows a comparison of the infinite sheet, thin plate and prism responses.
Compared to the plates, the prisms are imaged with higher conductivity values and depths
and actually come very close to the infinite sheet model except for the lower conductivity
values following the main positive peak. Responses obtained from prisms with a high
conductivity contrast to the host rock are presented in Figures 4-56 to 4-59. Similar
patterns are observed as with the low contrast case. However, the decreasing depth
associated with high contrasts is visible on the 300 m prism but not the 300 m plate. Also,
the high contrast prisms do not match the high contrast infinite sheet as closely as with the
low contrast models.
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