Page 16 - Oil&Gas-AustralAsia-2015-Issue-3
P. 16
A PPEA 2015 REVIEW
Feasibility (Figure 2)
Wireline logs (in Figure 3a) from a
borehole 250 m from the stimulation
well were used to derive predicted MT
responses resulting from the stimula-
tion (in Figure 3b). Two fluid models
were generated of the shale resistivity
after hydraulic stimulation, with a 50
m thick layer of resistivity either 1 Ωm
(in yellow) or 10 Ωm (in green) at 2900
m. Figure 3b show change of less than
1% between the pre- and post-stimula-
tion models with a 10 Ωm zone, which
would be too small to detect. However,
a model with a 50 m layer of resistivity
1 Ωm yields change of 4-7% in the MT
response, which is detectable using MT
equipment.
Survey
Separate MT responses were com-
puted on approximately daily basis
for as many of the 40 sites as possible,
dependent on noise. Figure 4 shows the
MT responses from a site close to the
injection on two separate days, one pri-
or (blue) and one post (red) hydraulic
stimulation. Such initial results show a
similar change as predicted in the feasi-
bility study in Figure 3b, similar to that
expected from the feasibility modelling
based on a 50 m thick 1 Ωm layer at
2900 m.
(Figure 4) (Figure 3A & 3B) The observational changes provides the
first evidence that sub-surface injected
fluids can be detected on the surface by
the MT method. §
REFERENCES AND
AThCiKs aNrOticWleLisEaDcGoEnMdeEnNseTdSversion
of the paper, Carter, S., Heinson, G.,
Krieger, L., Rees, N., Conway, D.,
Putland, O., Rugari, J., Boren, G.,
Matthews, C., Monitoring of hydraulic
fracturing in Moomba South Australia
using magnetotellurics. APPEA Jour-
nal, volume 55 (2015), pages 149–162.,
where the interested reader can find
further details, and a complete list of
references. We would like to thank San-
tos for making this project possible. The
Australian Geophysical Observing Sys-
tem (AGOS) are thanked for funding
this project, as part of the sub-surface
observatory program. Magnetotelluric
equipment was made available through
AuScope.
A A14 OIL & GAS ustral SIA JULY/AUGUST 2015 www.oilandgasaustralasia.com
Feasibility (Figure 2)
Wireline logs (in Figure 3a) from a
borehole 250 m from the stimulation
well were used to derive predicted MT
responses resulting from the stimula-
tion (in Figure 3b). Two fluid models
were generated of the shale resistivity
after hydraulic stimulation, with a 50
m thick layer of resistivity either 1 Ωm
(in yellow) or 10 Ωm (in green) at 2900
m. Figure 3b show change of less than
1% between the pre- and post-stimula-
tion models with a 10 Ωm zone, which
would be too small to detect. However,
a model with a 50 m layer of resistivity
1 Ωm yields change of 4-7% in the MT
response, which is detectable using MT
equipment.
Survey
Separate MT responses were com-
puted on approximately daily basis
for as many of the 40 sites as possible,
dependent on noise. Figure 4 shows the
MT responses from a site close to the
injection on two separate days, one pri-
or (blue) and one post (red) hydraulic
stimulation. Such initial results show a
similar change as predicted in the feasi-
bility study in Figure 3b, similar to that
expected from the feasibility modelling
based on a 50 m thick 1 Ωm layer at
2900 m.
(Figure 4) (Figure 3A & 3B) The observational changes provides the
first evidence that sub-surface injected
fluids can be detected on the surface by
the MT method. §
REFERENCES AND
AThCiKs aNrOticWleLisEaDcGoEnMdeEnNseTdSversion
of the paper, Carter, S., Heinson, G.,
Krieger, L., Rees, N., Conway, D.,
Putland, O., Rugari, J., Boren, G.,
Matthews, C., Monitoring of hydraulic
fracturing in Moomba South Australia
using magnetotellurics. APPEA Jour-
nal, volume 55 (2015), pages 149–162.,
where the interested reader can find
further details, and a complete list of
references. We would like to thank San-
tos for making this project possible. The
Australian Geophysical Observing Sys-
tem (AGOS) are thanked for funding
this project, as part of the sub-surface
observatory program. Magnetotelluric
equipment was made available through
AuScope.
A A14 OIL & GAS ustral SIA JULY/AUGUST 2015 www.oilandgasaustralasia.com
