Geoscience Reference
In-Depth Information
min
-1
)
9:40-10.34 (2000 l
Injection well
-20
-2
Production
well
-1
AE sensor
-10
0
AE sensor
1
0
Fracture
(711-719 m)
3
2
20
3
4
N
5
10
Electrodes
Injection well
-20
-10
0
10
20
(a)
(c)
Position
x
(m)
(10
-3
m
3
s
-1
)
2500
41.5
10:28
10:50
Injection well
33.3
2000
0
10:17
1500
25.0
10:27
400
+
10:10
-
1000
16.6
+
10:15
800
+
10:03
+
8.3
1200
500
10:08
800
800
10:01
0
0
0
0
N
10:40
9:40
10:00
10:20
11:00
800
Time (h:min)
Hypocenter AE
+
-
Positive and negative poles
(b)
(d)
Figure 5.14
Hydraulic fracturing test and resulting electrical potential (SP stands for
) and acoustic emissions (AE)
data from Ushijima et al. (1999).
a)
Field operations. Sketch of the position of the hydraulic fracturing.
b)
Water injection flow
used during the hydraulic fracturing experiment showing the flow rate history.
c)
SP changes (inmV) with respect to the SP distribution
at time 9:40, prior to the fracturing tests.
d)
Hypocenters determined from the AE and positions of the positive and
negative electrical potential poles inverted from the distribution of the electrical potential distribution at the ground surface.
“
self-potential
”
5.3 Hydraulic fracturing laboratory
experiment
fields (Kohl et al., 1979). Hydraulic fracturing can also
be used for the nonexempt solid waste disposal (Keck &
Withers, 1979) and in situ stress measurements
(Kuriyagawa et al., 1989) and can occur during the grout-
ing of the foundations of dams (Lee et al., 1999). The tra-
ditional method used for monitoring the progress of the
hydraulic fracturing process remains AE (microseismic).
Significant progress has been made in the last decade
with passive seismic monitoring methods used to detect
5.3.1 Background
Hydraulic fracturing has become a very important
method to increase the permeability of shales and tight
sandstones (Agarwal et al., 1979) for hydrocarbon recov-
ery and to increase the heat coupling to thermal transport
fluids to improve the energy production of geothermal
