Specifications

University of Pretoria etd – Combrinck, M (2006)
Figure 4-49: Cumulative conductance for a 2 S/m plate of 20 m thickness at 150 m
depth in 0.02 S/m host rock. The horizontal dimensions vary from 100 m to
infinite. ..........................................................................................................................................85
Figure 4-50: Imaged conductivity for a 2 S/m plate of 20 m thickness at 150 m depth in
0.02 S/m host rock. The horizontal dimensions vary from 100 m to infinite...............86
Figure 4-51: Imaged conductivity for a 2 S/m plate of 20 m thickness at 150 m depth in
0.02 S/m host rock. The horizontal dimensions vary from 100 m to infinite;
linear scale.....................................................................................................................................86
Figure 4-52: Cumulative conductance for a 0.2 S/m prism at 150 m depth in a 0.02
S/m host rock. The prism dimensions vary from 100 m to 400 m. ................................87
Figure 4-53: Imaged conductivity for a 0.2 S/m prism at 150 m depth in a 0.02 S/m
host rock. The prism dimensions vary from 100 m to 400 m. .........................................88
Figure 4-54: Imaged conductivity for a 0.2 S/m prism at 150 m depth in a 0.02 S/m
host rock. The prism dimensions vary from 100 m to 400 m; linear scale.....................88
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.............................89
Figure 4-56: Cumulative conductance for 2 S/m prisms at 150 m depth in a 0.02 S/m
host rock. The prism dimensions vary from 100 m to 400 m. .........................................90
Figure 4-57: Imaged conductivity for 2 S/m prisms at 150 m depth in a 0.02 S/m host
rock. The prism dimensions vary from 100 m to 400 m. ..................................................90
Figure 4-58: Imaged conductivity for 2 S/m prisms at 150 m depth in a 0.02 S/m host
rock. The prism dimensions vary from 100 m to 400 m; linear scale..............................91
Figure 4-59 : Comparison between imaged conductivities of 2 S/m prisms, 20 m thick
plates and infinite sheet of 20 m thickness at 150 m depth in a 0.02 S/m host
rock. Plates and prisms with horizontal dimensions of 200 m and 300 m are
shown. ...........................................................................................................................................91
Figure 4-60: Examples of field data showing "returning smoke ring” behaviour (stations
-1200 and -150 from line 4950, Rosh Pinah data set).
.........................................................92
Figure 4-61: S-layer differential transform results (conductivity depth section) on
synthetic data. Top: Thin vertical plate (400mX 400m X 20m) .......................................94
Figure 4-62: Same models as in Figure 4-63. Red dots indicate half space decay
behaviour and blue dots indicate conductor in “free air” decay........................................95
Figure 5-1: Mountain with TDEM survey team............................................................................... 101
Figure 5-2: Grid locality and layout. .................................................................................................. 102
Figure 5-3: Line 4950, Station 100. Top: Raw data with calculated cumulative conductance
and imaged conductivity. Middle: No filter effect on input data values, only on
cumulative conductance curve with imaged conductivity of filtered conductance
values. Bottom: Input data filtered for late channel erratic behaviour and filtered
cumulative conductance values. ............................................................................................ 104
Figure 5-4: Line 4950, Station 300. Top: Raw data with calculated cumulative conductance
and imaged conductivity. Middle: No filter effect on input data values, only on
cumulative conductance curve with imaged conductivity of filtered conductance
values. Bottom: Input data filtered for late channel erratic behaviour and filtered
cumulative conductance values. ............................................................................................ 105
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