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10 -4 S m -1
10 -6
ˆ
0
Q V
k 0
ˆ
Q V
5000
0 = 1.4 ± 0.Cm −3
σ S =
C 0 =
ƞ w =
σ w
σ s
+
10 −3 Sm -1
(1.2 ± 0.3)
×
F
4000
3.10 -4 S m -1
3000
10 -7
2000
1000
10 -3 S m -1
0 0
Berea sandstone
50
100
150
200
10 -8
0.01
Hydraulic head (cm)
0.1
1
Figure 2.10 Example of three typical runs for a core sample (in
the present case, glass beads with grain size of 212
Pore water conductivity (S m -1 )
m) at
three pore water conductivities. We observe linear relationships
between the variation of the streaming potentials and the
variation of the hydraulic heads at these different salinities.
At each salinity, the quasistatic streaming potential coupling
coefficient C 0 is obtained from the slope of these linear trends.
-
300
μ
Figure 2.11 Low-frequency streaming potential coupling
coefficient C 0 . The black circles correspond to themeasurements by
Zhu and Toksöz (2013) (Berea sandstone, porosity 0.23,
permeability 450mD, NaCl). The crosses correspond to the
laboratorymeasurements byMoore et al. (2004) (Berea sandstone,
porosity 0.19, water). The plain line corresponds to the fit of the
proposed model to the data of Zhu and Toksöz (2013) only.
-50
-40
-30
-20
-10
0
10
20
2E05
0
Kaolinite
IEP
-2E05
4
5
6
7
8
9
10 11
IEP
pH
-4E05
-6E05
Berea sandstone
-8E05
Porosity 0.095
Pore size 12.8
μ
m
-1E06
-1.2E06
0
2
4
6
8
10
pH
Figure 2.12 Dependence of the seismoelectric current with the pH for a water-saturated Berea sandstone (data from Dukhin et al.,
2010). The plain line is a guide for the eyes. IEP corresponds to the isoelectric point for which the zeta potential of the mineral is equal to
zero. The Berea sandstone is mainly made of silica grains with some kaolinite. The insert corresponds to zeta potential data reported by
Leroy and Revil (2004) for kaolinite (NaCl, 2 × 10 3 Mol l 1 ). The plain line corresponds to the prediction of a triple layer model.
 
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