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October 29, 2015
Gather Conditioning, Processing
Impact on AVO and Rock
Property Prediction
Roger A. Young
October 29, 2015
Seismic PetrophysicsThe Careful Synthesis of
Seismic and Well Logs
October 29, 2015
Alpine FieldNorth Slope, Alaska
A tale of a Billion Barrels
October 29, 2015
Creating a Valid Model
Bergschrund #1 Well
Well Log Information as Logged
October 29, 2015
Creating a Valid Model
Bergschrund #1 Well
Well Log Information as Logged
Modeled
Gather
Offset
October 29, 2015
Creating a Valid Model
Bergschrund #1 Well
Well Log Information as Logged
Modeled
Gather Actual
Nearby
Gather
Offset Offset
October 29, 2015
Creating a Valid Model
Modeled
Gather Actual
Nearby
Gather
Bergschrund #1 Well
Well Log Information Corrected
Offset Offset
October 29, 2015
Some Thoughts on Correcting the Logs
October 29, 2015
Raw Log Curves
After Median
Smoother
GR SP Rt Dt Rhob Nphi Cali
October 29, 2015
RT replaces the
HF part of rhob.
Result is no real
change.
GR SP Rt Dt Rhob Nphi Cali
October 29, 2015
Log editing
using Rt as a
constraint
where logs go
bad.
Previous Slide
Focus
GR SP Rt Dt Rhob Nphi Cali
October 29, 2015
Constraining Logs with Eigen Vectors
GR SP Rt Dt Rhob Nphi Cali
Input = Green 3 vectors depth variant = Black
October 29, 2015
Rhob Nphi GR Grain Density
from input
Nphi Rhob
Vclay
Overlay
October 29, 2015
Rhob Nphi GR Grain Density
from output
Nphi Rhob
Vclay
Overlay
October 29, 2015
Log Analysis Workflow
Input Well Logs Rocks
Inversion
DT Density Nphi RT GR SP
October 29, 2015
Log Analysis Workflow
Input Well Logs Rocks Output Logs
Inversion Forward modeling
DT Density Nphi RT GR SP DT Density Shear
October 29, 2015
Synthetic Tie
Synthetic Tie Before
October 29, 2015
Synthetic Tie
Synthetic Tie Before Synthetic Tie After
October 29, 2015
Typical Multi-Well Example
October 29, 2015
Deep Resistivity
All RT
curves are
in
alignment
October 29, 2015
Sonic
Not the
case with
DT
October 29, 2015
Density
Not the
case with
Rhob
October 29, 2015
Sonic
October 29, 2015
Density
October 29, 2015
Initial Model for Inversion
October 29, 2015
Rhob
Raw Logs
Full Bandwidth
4 Wells
October 29, 2015
Rhob
Raw Logs
0 – 10 Hz
4 Wells
October 29, 2015
Rhob
FM Logs
0 – 10 Hz
4 Wells
Model Normalization
October 29, 2015
Rhob
FM Logs
0 – 10 Hz
4 Wells
Model Normalization
Spectral Recursive
Inversion
October 29, 2015
Rhob, FM Logs
0 – 10 Hz
4 Wells
Model Normalization
Spectral Recursive
Inversion
Black Logs FM
Green Inversion
October 29, 2015
Seismic Processing for Inversion
October 29, 2015
Residual NMO Multiple Removal NMO Stretch
Seismic Data Preparation
October 29, 2015
Before Scaling
October 29, 2015
After Scaling
October 29, 2015
Model
October 29, 2015
Oil
Sand
Shale
Creating the Model
Lithology Porosity
October 29, 2015
Pore Pressure Resulting Full Offset Stack
Velocity
Creating the Model
October 29, 2015
The Perfect ModelGathers
Near and Far Stacks
Intercept (P) Gradient (G)
P vs G cross plots
AVO Types
Lithology Inversion
Velocity Inversion
Density Inversion
October 29, 2015
Single Trace Scaler
October 29, 2015
Every 20th gather P Stack G Stack
Perfect Model
October 29, 2015
Single trace scaler
Every 20th gather P Stack G Stack
October 29, 2015
Cross Plot of P vs G
Color is Porosity
Perfect Model
Inverted Space
October 29, 2015
Single trace scaler
Cross Plot of P vs G
Color is Porosity
Inverted Space
October 29, 2015
OIL
-------
SAND
-------
SHALE
Perfect Model
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
Single trace scaler
OIL
-------
SAND
-------
SHALE
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
1000ms AGC Scaler
October 29, 2015
Every 20th gather P Stack G Stack
Perfect Model
October 29, 2015
AGC Scaler
Every 20th gather P Stack G Stack
October 29, 2015
Cross Plot of P vs G
Color is Porosity
Perfect Model
Inverted Space
October 29, 2015
AGC Scaler
Cross Plot of P vs G
Color is Porosity
Inverted Space
October 29, 2015
OIL
-------
SAND
-------
SHALE
Perfect Model
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
AGC Scaler
OIL
-------
SAND
-------
SHALE
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
NMO Stretch
October 29, 2015
Every 20th gather P Stack G Stack
Perfect Model
October 29, 2015
NMO Stretch
Every 20th gather P Stack G Stack
October 29, 2015
Cross Plot of P vs G
Color is Porosity
Perfect Model
Inverted Space
October 29, 2015
NMO Stretch
Cross Plot of P vs G
Color is Porosity
Inverted Space
October 29, 2015
OIL
-------
SAND
-------
SHALE
Perfect Model
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
NMO Stretch
OIL
-------
SAND
-------
SHALE
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
Automatic
High Resolution NMO
October 29, 2015
Every 20th gather P Stack G Stack
Perfect Model
October 29, 2015
High Resolution RNMO
Every 20th gather P Stack G Stack
October 29, 2015
Cross Plot of P vs G
Color is Porosity
Perfect Model
Inverted Space
October 29, 2015
High Resolution RNMO
Cross Plot of P vs G
Color is Porosity
Inverted Space
October 29, 2015
OIL
-------
SAND
-------
SHALE
Perfect Model
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
High Resolution RNMO
OIL
-------
SAND
-------
SHALE
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
AGC, NMO Stretch
October 29, 2015
Every 20th gather P Stack G Stack
Perfect Model
October 29, 2015
AGC, NMO Stretch
Every 20th gather P Stack G Stack
October 29, 2015
Cross Plot of P vs G
Color is Porosity
Perfect Model
Inverted Space
October 29, 2015
AGC, NMO Stretch
Cross Plot of P vs G
Color is Porosity
Inverted Space
October 29, 2015
OIL
-------
SAND
-------
SHALE
Perfect Model
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
AGC, NMO Stretch
OIL
-------
SAND
-------
SHALE
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
1000ms AGC Scaler
Then
Apply Offset Scaler to Correct
October 29, 2015
Every 20th gather P Stack G Stack
Perfect Model
October 29, 2015
Every 20th gather P Stack G Stack
AGC Scaler + Offset Scaler
October 29, 2015
Cross Plot of P vs G
Color is Porosity
Perfect Model
Inverted Space
October 29, 2015
AGC Scaler
Cross Plot of P vs G
Color is Porosity
Inverted Space
October 29, 2015
Cross Plot of P vs G
Color is Porosity
AGC Scaler + Offset Scaler
Inverted Space
October 29, 2015
OIL
-------
SAND
-------
SHALE
Perfect Model
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
AGC Scaler
OIL
-------
SAND
-------
SHALE
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
OIL
-------
SAND
-------
SHALE
AGC Scaler + Offset Scaler
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
NMO Stretch
Then
Filter Back to Far Offset Frequency
Content
October 29, 2015
Every 20th gather P Stack G Stack
Perfect Model
October 29, 2015
NMO Stretch
Every 20th gather P Stack G Stack
October 29, 2015
Every 20th gather P Stack G Stack
NMO Stretch then Filter Back
October 29, 2015
Cross Plot of P vs G
Color is Porosity
Perfect Model
Inverted Space
October 29, 2015
NMO Stretch
Cross Plot of P vs G
Color is Porosity
Inverted Space
October 29, 2015
Cross Plot of P vs G
Color is Porosity
NMO Stretch then Filter Back
Inverted Space
October 29, 2015
OIL
-------
SAND
-------
SHALE
Perfect Model
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
NMO Stretch
OIL
-------
SAND
-------
SHALE
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
OIL
-------
SAND
-------
SHALE
NMO Stretch then Filter Back
Inverted Space
Cross Plot of P vs G
Color is Lithology
Shale is Green
Sand is Yellow
Oil is Red
October 29, 2015
Conclusion: Rock-Based Integration
THE
ROCKS
Petrophysical Geological
Engineering Geophysical
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