M onitoring of CO 2 injected at Ketzin using 3D time-lapse seismic data
Seismic integration in the modelling of injected sands - … · Development of Producing Areas,...
20
June 11, 2012 Development of Producing Areas, Aberdeen Seismic integration in the modelling of injected sands Duncan Chedburn Kirsten Gray, Alison Jagger 1 , Gary Marsden 2 and Richard Todd ( 1 Centrica, 2 Marsden Geophysical Consulting Ltd)
-
Upload
phungkhanh -
Category
Documents
-
view
218 -
download
5
Transcript of Seismic integration in the modelling of injected sands - … · Development of Producing Areas,...
June 11, 2012 Development of Producing Areas, Aberdeen
Seismic integration in the modelling of injected sands
Duncan Chedburn
Kirsten Gray, Alison Jagger1, Gary Marsden2 and Richard Todd
(1 Centrica, 2 Marsden Geophysical Consulting Ltd)
June 11, 2012
Agenda
Introduction to Area
Geological Setting
Geophysical Workflow
Static Modelling
Conclusions
Quad
9
Development of Producing Areas, Aberdeen
June 11, 2012
Introduction
• Quad 9 block – Gryphon field producing since 1993
• > 100 well penetrations in Gryphon
• Modelling area - 26 km2
• Main purpose of model – development opportunities for the gas cap
Aims of modelling
• Fit for purpose model, focussed on gas
• Define Gas Volumes and Uncertainty
• Suitable for dynamic modelling
• Incorporated as much determinism in the model as possible despite difficult geological geometries
• Repeatable and easy to update model (New seismic in 2012 and ongoing drilling)
0 1.5km
Gryphon
Development of Producing Areas, Aberdeen
June 11, 2012
Geological Setting
Reservoir
EARLY EOCENE
Development of Producing Areas, Aberdeen
5619.00’ 5622.00’ 5625.00’ 5628.00’
5628.00’ 5631.00’ 5622.00’ 5625.00’
DYKE
DYKE INJECTION BRECCIA
DYKE
GOC
Feeder dyke system
DYKE
Stepped discordant base
Injectites
Development of Producing Areas, Aberdeen June 11, 2012
June 11, 2012
Geophysical Workflow
0 1000m Far Offset Coloured Inversion Cube
LOCATION MAP !!
Tullich
0 2500m
Gryphon
Harding
Maclure
A B
A B
Development of Producing Areas, Aberdeen
June 11, 2012
In Situ Sands
0 1000m
LOCATION MAP !!
Tullich
0 2500m
Gryphon
Harding
Maclure
A B
A B Far Offset Coloured Inversion Cube
Development of Producing Areas, Aberdeen
June 11, 2012
Injectites
0 1000m
LOCATION MAP !!
Tullich
0 2500m
Gryphon
Harding
Maclure
A B
A B Far Offset Coloured Inversion Cube
Development of Producing Areas, Aberdeen
June 11, 2012
Point set extraction
0 1000m
LOCATION MAP !!
Tullich
0 2500m
Gryphon
Harding
Maclure
A B
A B Far Offset Coloured Inversion Cube
Development of Producing Areas, Aberdeen
June 11, 2012
Amplitude Analysis of Point Set
Tw
o W
ay T
ime (
ms)
Seismic Amplitude Seismic Amplitude
GOC
OWC
Development of Producing Areas, Aberdeen
June 11, 2012
Time Dependant Amplitude Cut Offs
GOC
OWC
Tw
o W
ay T
ime (
ms)
Seismic Amplitude Seismic Amplitude
Development of Producing Areas, Aberdeen
June 11, 2012
Creating Probability Point Sets
GOC
OWC
Tw
o W
ay T
ime (
ms)
Seismic Amplitude
Development of Producing Areas, Aberdeen
June 11, 2012
S1
S1
S1
S2
S2
S2
Ax
A1 A2
A1 A2
GOC
OWC
Example; • Consider a point with a measured amplitude of -0.80 • Evaluate sand probability in gas leg, oil leg & aquifer
Assume; • Sand prob at low amp threshold S1 = 0.2 • Sand prob at high amp threshold S2 = 1.0
Gas Leg; Ax = -0.8 Low amplitude threshold A1 = -0.50 High amplitude threshold A2 = -2.40 Sand Probability = 0.33 Oil Leg; Ax = -0.8 Low amplitude threshold A1 = -0.30 High amplitude threshold A2 = -1.35 Sand Probability = 0.58 Aquifer; Ax = -0.8 Low amplitude threshold A1 = -0.20 High amplitude threshold A2 = -0.93 Sand Probability = 0.86
Ax
Ax
12
12
11 SS
AA
AASS x
x
0.8
Deriving pseudo sand probability
De-fluidising the seismic response
Development of Producing Areas, Aberdeen
June 11, 2012
Generating sand probability cubes
0 1000m A B
Far Offset Coloured Inversion Cube
1
0
Development of Producing Areas, Aberdeen
June 11, 2012
Kriged Probability Cube
Seismic probability cube
uploaded into static model.
Data Kriged in model
1
0
0 1000m Far Offset Coloured Inversion Cube
Development of Producing Areas, Aberdeen
June 11, 2012
Sand proportion
Simple sand shale model Sand Distribution Map
Insitu sand body mapped on
seismic. Deterministic use of
seismic data - Stochastic
modelling of sand
Probability of sand body derived
from seismic. Probabilistic use of
seismic data - Stochastic
modelling of sand using kriged
data as trend
Development of Producing Areas, Aberdeen
1
0
June 11, 2012
Sand Distribution Section
0 1000m
Development of Producing Areas, Aberdeen
Work in Progress
June 11, 2012
Connectivity of sand in the model
0 1000m
Development of Producing Areas, Aberdeen
Work in Progress
June 11, 2012
Conclusions
• Modelling objectives – work in progress
• Direct incorporation of seismic into geological model to capture
complex geological geometries
• De-fluidising the seismic response
• Repeatable G&G workflow
• Incorporated as much determinism in the model as possible
• Probability method used to resolve issues faced in previous
model builds
• Simple fit for purpose model which is easily updateable and repeatable as required
Development of Producing Areas, Aberdeen
Acknowledgements
June 11, 2012
Gryphon Field Partner: Sojitz UK plc
Development of Producing Areas, Aberdeen
Marsden Geophysical Consulting Ltd.
