Characterization of Geotomographic Studies with the EMRE System
Table 2
The total attenuation losses (dB) as a function of material parameters and frequency. All other losses (e.g., in the device, different polarizations in transmission, and reception) are excluded.
Wavelength
Skin depths
Attenuation
Attenuation
Attenuation
Attenuation
Attenuation
(m)
(m)
(dB/m)
dB–200 m
dB–400 m
dB–600 m
dB–800 m
= 2500 m = 10 = 40
312 kHz
191
141
55
87
0.16
0.1
100
83
151
117
200
149
248
180
1000 kHz
85
47
44
84
0.19
0.1
108
83
168
117
225
149
282
180
2500 kHz
39
20
42
84
0.20
0.1
111
83
174
117
234
149
293
180
5000 kHz
19
9.5
42
84
0.20
0.1
111
83
174
117
234
149
293
180
= 5000 m = 10 = 40
312 kHz
240
149
94
170
0.09
0.05
81
69
113
89
142
107
171
123
1000 kHz
92
47
85
168
0.1
0.05
83
69
117
89
149
107
180
123
2500 kHz
39
20
84
168
0.1
0.05
83
69
117
89
149
107
180
123
5000 kHz
19
9.5
84
168
0.1
0.05
83
69
117
89
149
107
180
123
= 7500 m = 10 = 40
312 kHz
270
150
133
252
0.065
0.034
73
64
97
80
113
93
140
105
1000 kHz
93
47
126
252
0.068
0.034
74
64
99
80
122
93
144
105
2500 kHz
39
20
126
252
0.068
0.034
74
64
99
80
122
93
144
105
5000 kHz
19
9.5
126
252
0.068
0.034
74
64
99
80
122
93
144
105
= 10000 m = 10 = 40
312 kHz
282
151
174
337
0.049
0.026
68
62
88
75
106
87
122
96
1000 kHz
91
47
168
336
0.051
0.026
69
62
89
75
107
87
124
96
2500 kHz
39
20
168
336
0.051
0.026
69
62
89
75
107
87
124
96
5000 kHz
19
9.5
168
336
0.051
0.026
69
62
89
75
107
87
124
96
= 15000 m = 10 = 40
312 kHz
293
151
256
504
0.034
0.017
64
60
80
71
93
79
105
86
1000 kHz
94
47
252
504
0.034
0.017
64
60
80
71
93
79
105
86
2500 kHz
39
20
252
504
0.034
0.017
64
60
80
71
93
79
105
86
5000 kHz
19
9.5
251
504
0.034
0.017
64
60
80
71
94
79
105
86
Bold numbers are referred to as favourable conditions.
