Analysis of induced microseismic events Analysis of induced - - PowerPoint PPT Presentation

Analysis of induced microseismic events from HDR/EGS reservoirs by super resolution mapping techniques Analysis of induced microseismic events from HDR/EGS reservoirs by super resolution mapping techniques

*:Graduate School of Environmental Studies, Tohoku University, Japan **: MIL-TECH, UK ***: Geodynamics Ltd., Australia ****: JAPEX Research Center, Japan

• H. Asanuma*, Y. Kumano*, H. Niitsuma*, R. Baria**,
• D. Wyborn***, K. Tezuka****

Error in the mapping of microseismic events Error in the mapping of microseismic events

Error (residual) in mapping

• Uncertainty in velocity structure.
• Error in phase picking

Mapping methods with higher reliability/resolution. Spatial distribution

• f error

Estimated location

MTC (more than cloud) mapping technologies MTC (more than cloud) mapping technologies

Standard

3400 3200 3000 2800 2600 Depth(m) 200 100

• 100 -200

Along_N25W_direction(m)

JHD (1976)

3400 3200 3000 2800 2600 Depth(m) 200 100

• 100 -200

Along_N25W_direction(m) 3400 3200 3000 2800 2600 Depth(m) 200 100

• 100 -200

Along_N25W_direction(m)

Original Collapsing (Jones and Stewart 1995) Multiplet analysis (Moriya et. al, 1995)

Statistical

• ptimization

Similarity of waveform

Background of this study Background of this study

“Multiplet” analysis (Moriya et al., BSSA, 2003)

• Coherence-based analysis
• Estimation of the orientation of fracture, stress, and

pore pressure

Large CPU time and man-power (post-analysis)

JHD Multiplet analysis

Background of this study Background of this study

“Collapsing” method (Jones and Stewart, 1995)

• Statistical optimization of the seismic “cloud”
• Implicit assumption of hypocenters on a point

Difficulty in the interpretation of the “Collapsed” hypocenters

Jones and Stewart, MTC Project report (1998) True location “Blurred” location by error in velocity model or picking (JHD) Statistical

• ptimization

Optimized location (Collapsing)

“Blurred” location by error in velocity model or picking (JHD) Relocation by the

• riginal Collapsing

Relocation by the Coherence Collapsing

Concept of the Coherence Collapsing Concept of the Coherence Collapsing

Station correction is canceled

Identical path Monitoring station

Precise differential

• bs

j k i k cal j k i k ij k

) t (t ) t (t dr − − − =

Concept of the DD (double differential) Concept of the DD (double differential)

Concept of the DD (double differential) Concept of the DD (double differential)

DD Equation

• bj

j k i k cal j k i k ij k

t t t t dr ) ( ) ( − − − =

*Link of events with higher similarity *Precise relative picking

Super resolution mapping Super resolution mapping

Background of this study Background of this study

The Coherence Collapsing The DD

• Statistical optimization of the

whole seismic cloud emphasizing the location of multiplets

• Ability to delineate large-scale

seismic structures

• Absolute location
• Small CPU-time (semi-realtime)
• Coherence analysis of seismic

signals with higher similarity

• Ability to delineate small-scale

seismic structures which may be highly correlated to existing fracture and stress state.

• Relative timing and location
• Large CPU-time (post analysis)

SH Sh

Application to the data set from Soultz Application to the data set from Soultz

Application to the data set from Soultz Application to the data set from Soultz

Application to the data set from Soultz Application to the data set from Soultz

Application to the data set from Soultz Application to the data set from Soultz

Darwin Brisbane Nockatunga Hunter Valley Sydney Melbourne Perth Adelaide

Cooper Basin

(Geodynamics Limited)

Application to the data set from Cooper Basin, Aus. Application to the data set from Cooper Basin, Aus.

Application to the data set from Cooper Basin, Aus. Application to the data set from Cooper Basin, Aus.

• 2000
• 1000

1000 2000 NS(m)

• 2000
• 1000

1000 2000 EW(m) 6000 5000 4000 3000 2000 Depth(m)

• 2000
• 1000

1000 2000 EW(m) 6000 5000 4000 3000 2000 Depth(m) 2000 1000

• 1000
• 2000

NS(m)

MW1 MW2 MW3 Mcleod1 Habanero1 Habanero1 Habanero1

Application to the data set from Cooper Basin, Aus. Application to the data set from Cooper Basin, Aus.

Application to the data set from Cooper Basin, Aus. Application to the data set from Cooper Basin, Aus.

Akebono Minami Yufutsu C.T. Far Harumi C.T. Near PS3 UP PS3 LOW

Application to the data set from Yufutsu gas field, JPN. Application to the data set from Yufutsu gas field, JPN.

Application to the data set from Yufutsu gas field, JPN. Application to the data set from Yufutsu gas field, JPN.

Application to the data set from Yufutsu gas field, JPN. Application to the data set from Yufutsu gas field, JPN.

Application to the data set from Yufutsu gas field, JPN. Application to the data set from Yufutsu gas field, JPN.

JHD Coh-col DD

Problems to be solved Problems to be solved

The Coherence Collapsing The DD

• Optimization of the parameters

(weighting factor, definition of the error ellipsoid)

• “Over collapsing”
• Error evaluation
• Possible artifacts
• Determination of the absolute

location

The use of the super-resolution mapping techniques in the seismic monitoring of HDR/EGS reservoirs The use of the super-resolution mapping techniques in the seismic monitoring of HDR/EGS reservoirs Phase picking SEL (single event location) JHD (joint hypocenter determination) Original Collapsing

Coherence table

Coherence Collapsing Double differential Further analysis

*Source mechanism *Magnitude *Stress state *Flow path …..

Automatic picking

Realtime (0-5 min.) Semi-realtime (10-20 min.) Post-analysis (1-10 days)

• Outline of the

stimulated zone

• Optimization of the

velocity model

• Large scale seismic

structure

• Location of the

multiplet cluster

• Structure of the

multiplet cluster

• Spatial error

Thank you for your kindly attention Thank you for your kindly attention