Geonics Limited EM31-SH, Operating Manual

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EM31-SH MANUAL Page
29
σ
a =
σ
1
[1.000-R(Z
1
)+k
2
R(Z
1
)-k
2
R(Z
2
)+k
3
R(Z
2
)]
k
2
= = = 0.10
k
3
= = 1.00
(A)
σ
a
=10 (1.00–0.59+(0.10x0.45)-(0.10x0.32)+(1.00x0.32)) = 8.83 mmho/m
(B)
σ
a
=10 (1.00–0.59+(0.10x0.45)-(0.10x0.24)+(1.00x0.24)) = 8.11 mmho/m
(C)
σ
a
=10 (1.00–0.59+(0.10x0.45)-(0.10x0.20)+(1.00x0.20)) = 7.75 mmho/m
(D)
σ
a
=10 (1.00–0.59+(0.10x0.45)-(0.10x0.14)+(1.00x0.14)) = 7.21 mmho/m
Fig. 7 CROSS SECTION GRAVEL DEPOSIT
=
1.000 - R(Z
1
) + k
2
R(Z
1
)
k
2
= = 0.0033
Z
1
= 5m,
σ
a
= 30(1.00 – 0.20) = 24.0 mmho/m
Z
1
= 3m,
σ
a
= 30(1.00 – 0.32) = 20.4 mmho/m
Z
1
= 1m,
σ
a
= 30(1.00 – 0.71) = 8.77 mmho/m
Fig. 6 CROSS SECTION BEDROCK HIGH
= 1.000 - R(Z
1
) + k
2
R(Z
1
) (1)
k
2
= = = 5
Z
1
= 1m,
σ
a
= 8(1.00 – 0.71 + (5 x 0.71)) = 30.7 mmho/m
Z
1
= 2m,
σ
a
= 8(1.00 – 0.45 + (5 x 0.45)) = 22.4 mmho/m
Z
1
= 5m,
σ
a
= 8(1.00 – 0.20 + (5 x 0.20)) = 14.4 mmho/m
Z
1
= 7m,
σ
a
= 8(1.00 – 0.14 + (5 x 0.14)) = 12.5 mmho/m
Fig. 5 CROSS SECTION BURIED RIVER VALLEY
σ
a
σ
1
σ
2
σ
1
40
8
σ
a
σ
1
0.1
30
σ
3
σ
1
σ
2
σ
1
1
10