Interpretational Applications of Spectral Decomposition Greg Partyka, James Gridley, and John Lopez.
This PowerPoint version of the material, was compiled by Greg Partyka (October 2006)
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Transcript of This PowerPoint version of the material, was compiled by Greg Partyka (October 2006)
Designing Optimum Zero-Phase Wavelets
R. S. Kallweit and L. C. WoodAmoco Houston DivisionDGTS January 12, 1977
This PowerPoint version of the material, was compiled by Greg Partyka (October 2006) G. Partyka (Oct 06)
Wavelet Shape and Sidelobe Interference
• Wavelets designed with a vertical or near-vertical high end slope exhibit high frequency sidelobes that can cause significant distortions in reflection amplitudes and associated event character.
• An alternate wavelet is proposed called the Texas Double in recognition of the primary characteristic being a 2-octave slope on the high frequency side.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Texas Double Wavelets
• Time Domain Characteristics:– negligible high frequency sidelobe tuning effects.– maximum peak-to-sidelobe amplitude ratios.
• Frequency Domain Characteristics:– vertical or near-vertical low-end slope.– 2-octave linear slope on the high-end. Amplitudes are measured
using a linear rather than decibel scale.– end frequencies correspond to the highest and lowest recoverable
signal frequency components of the recorded data.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of High Frequency Side-Lobes
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
High frequency sidelobes can be attenuated to an insignificant levelvia a 2-octave or greater high side slope.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of High Frequency Side-Lobes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
High frequency sidelobes can be attenuated to an insignificant levelvia a 2-octave or greater high side slope.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of High Frequency Side-Lobes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
3 octave slope
High frequency sidelobes can be attenuated to an insignificant levelvia a 2-octave or greater high side slope.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of High Frequency Side-Lobes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
2 octave slope
High frequency sidelobes can be attenuated to an insignificant levelvia a 2-octave or greater high side slope.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of High Frequency Side-Lobes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
1 octave slope
High frequency sidelobes can be attenuated to an insignificant levelvia a 2-octave or greater high side slope.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of High Frequency Side-Lobes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
High frequency sidelobes can be attenuated to an insignificant levelvia a 2-octave or greater high side slope.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of Low Frequency Side-Lobes
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
Low frequency sidelobes are a function of the wavelet’s bandpass.They cannot be reduced beyond what is shown here.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of Low Frequency Side-Lobes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
Low frequency sidelobes are a function of the wavelet’s bandpass.They cannot be reduced beyond what is shown here.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of Low Frequency Side-Lobes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
4.0 octaves
Low frequency sidelobes are a function of the wavelet’s bandpass.They cannot be reduced beyond what is shown here.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of Low Frequency Side-Lobes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
3.0 octaves
Low frequency sidelobes are a function of the wavelet’s bandpass.They cannot be reduced beyond what is shown here.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of Low Frequency Side-Lobes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
2.4 octaves
Low frequency sidelobes are a function of the wavelet’s bandpass.They cannot be reduced beyond what is shown here.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Development of Low Frequency Side-Lobes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
2.0 octaves
Low frequency sidelobes are a function of the wavelet’s bandpass.They cannot be reduced beyond what is shown here.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
High Frequency Held Constant (Klauder Wavelets)
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
High Frequency Held Constant (Klauder Wavelets)
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
4.0 octaves
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
High Frequency Held Constant (Klauder Wavelets)
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
3.0 octaves
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
High Frequency Held Constant (Klauder Wavelets)
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
2.4 octaves
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
High Frequency Held Constant (Klauder Wavelets)
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
2.0 octaves
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
High Frequency Held Constant (Klauder Wavelets)
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
1.4 octaves
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Decreasing the Low Frequency Slope
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Decreasing the Low Frequency Slope
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
3 octaves
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Decreasing the Low Frequency Slope
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
2 octave slope
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Decreasing the Low Frequency Slope
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
3 octave slope
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Decreasing the High and Low Frequency Slopes
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Decreasing the High and Low Frequency Slopes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
3 octave sinc
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Decreasing the High and Low Frequency Slopes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Decreasing the High and Low Frequency Slopes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Decreasing the High and Low Frequency Slopes
frequency
100
am
plit
ud
e
20 30 40 50 60
REFLECTIVITY IMPEDANCE0
100
Tra
vel T
ime
(m
s)
200
300
50
150
250
0
100
200
300
50
150
250
Temporal Thickness (ms)
0 5040302010
Temporal Thickness (ms)
50403020100
Texas Double
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Texas Double in Practice
• One may implement the Texas Double on real data by first running an amplitude whitening program followed by a 2-octave slope Ormsby filter.
• The Texas Double design criteria should not be a goal of data acquisition.
• It is of utmost importance that the signal-to-noise ratio of the high-frequency components be as large as possible, and therefore filtering process such as the Texas Double should occur in data processing and not in data acquisition.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Example Amplitude Response of Dynamite Data
0.4
0.6
0.8
1.0a
mp
litu
de
Frequency (Hz)
0
0.2
04020 60 70 9010
Raw
Whitened
Texas Double
30 50 80 100
The Texas Double in effect does not attenuate the high frequency components of the recorded data,but rather amplifies them less than the conventional whitened output obtained using program DAFD.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Proposed Standard Equi-Resolution Comparison
• One of the difficulties involved in trying to compare traces containing different zero-phase wavelets designed over identical bandpasses is the question of what to compare and measure each trace against.
• It is rather unsatisfactory to compare the traces against one another since there are too many unknowns.
• A standard comparison is needed.• The standard trace proposed is one where the convolving wavelet
has the same temporal resolution as the sinc wavelet over a given bandpass but has no sidelobes whatsoever.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Temporal Resolution – Low-Pass Sinc vs Low-Pass Texas Double
0
10
20
30
pe
ak-
to-t
rou
gh
se
pa
ratio
n (
ms)
0 10 20 30
spike separation (ms)
0–0-62-64 HzSinc
TR
0
10
20
30
pe
ak-
to-t
rou
gh
se
pa
ratio
n (
ms)
0 10 20 30
spike separation (ms)
TR
Conclusion: Over a given low-pass, temporal resolution of the Texas Double wavelet equals 80% of the temporal resolution of the sinc wavelet.
TR = 1 / 1.5f4
0–0-20-80 HzTexas Double
TR = 1 / 1.2f4
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Equivalent Temporal Resolution: Ormsby to Low-Pass Sinc
fs
frequency
ampl
itude
f4
f3
0.5
0.6
0.7
f s/f
4
0.8
0.9
1.0
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
f3 / f4
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Is it worth giving up the 20% loss in Temporal Resolution?
• Can the benefits associated with attenuating high-frequency sidelobes outweigh the 20% loss in temporal resolution?
• The following well-log based comparisons, suggest that they can.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Well-Log Comparison
raw 00-00-20-80
00-00-62-64
08-09-62-64
08-09-16-64
08-09-20-80
Ra
w I
np
ut
L
ay
eri
ng
or
Re
fle
cti
vit
y
De
sir
ed
Sta
nd
ard
N
o S
ide
lob
es
(re
so
luti
on
of
a 6
4 H
z s
inc
)
Hig
h F
req
ue
nc
y T
un
ing
Eff
ec
ts O
nly
H
igh
Fre
qu
en
cy
Sid
elo
be
s(r
es
olu
tio
n o
f a
64
Hz
sin
c)
Ne
gli
gib
le E
ffe
ct
L
ow
Fre
qu
en
cy
Sid
elo
be
s(r
es
olu
tio
n o
f a
64
Hz
sin
c)
Sin
c W
av
ele
t
Hig
h a
nd
Lo
w F
req
ue
nc
y S
ide
lob
es
(re
so
luti
on
of
a 6
4 H
z s
inc
)
Te
xa
s D
ou
ble
L
ow
Fre
qu
en
cy
Sid
elo
be
s(8
0%
re
so
luti
on
of
of
a 6
4 H
z s
inc
)
• Any observed differences are due to sidelobe tuning or temporal resolution.
• To determine differences associated with sidelobes as opposed to those associated with temporal resolution, compare each trace to the 8-9-20-80 track.
• 2-octave and 3-octave bandpass wavelets:
• have identical terminal frequencies.
• have the same high frequency sidelobes and temporal resolution.
• allow low frequency sidelobes to be compared.
• Traces containing different wavelets but with the same temporal resolution can be compared in order to observe differences due to sidelobe tuning effects.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Well-Log Comparison - 3 Octaves
raw rc00-00-20-80
00-00-62-64
08-09-62-64
08-09-16-64
08-09-20-80
raw layering
00-00-20-80
00-00-62-64
08-09-62-64
08-09-16-64
08-09-20-80Layering Reflectivity
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Well-Log Comparison - 2 Octaves
raw rc00-00-20-80
00-00-62-64
16-17-62-64
16-17-18-64
16-17-20-80
raw layering
00-00-20-80
00-00-62-64
16-17-62-64
16-17-18-64
16-17-20-80Layering Reflectivity
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Well-Log Comparison - 3 Octaves
raw rc00-00-20-80
00-00-62-64
08-09-62-64
08-09-16-64
08-09-20-80
raw layering
00-00-20-80
00-00-62-64
08-09-62-64
08-09-16-64
08-09-20-80Layering Reflectivity
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Well-Log Comparison - 2 Octaves
raw rc00-00-20-80
00-00-62-64
16-17-62-64
16-17-18-64
16-17-20-80
raw layering
00-00-20-80
00-00-62-64
16-17-62-64
16-17-18-64
16-17-20-80Layering Reflectivity
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Well-Log Comparison - 3 Octaves
raw rc00-00-20-80
00-00-62-64
08-09-62-64
08-09-16-64
08-09-20-80
raw layering
00-00-20-80
00-00-62-64
08-09-62-64
08-09-16-64
08-09-20-80Layering Reflectivity
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Well-Log Comparison - 2 Octaves
raw rc00-00-20-80
00-00-62-64
16-17-62-64
16-17-18-64
16-17-20-80
raw layering
00-00-20-80
00-00-62-64
16-17-62-64
16-17-18-64
16-17-20-80Layering Reflectivity
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Well-Log Examples
• The following figures illustrate the sensitivity of the side-lobe tuning effects of the sinc and Texas Double wavelets to small changes in high frequency components.
• The layered log and corresponding reflectivity were filtered holding the low side constant for each filter and varying the high side in 1 Hz increments.
• Since the filters change in a linear and gradual manner, we would hope that the traces would do likewise. Unfortunately, significant trace-to-trace variations are apparent.
• Two sets of Texas Double filters are also applied, and compared with the sinc wavelet results. One Texas Double set exhibits the same temporal resolution as the bandpass sinc set. The other Texas Double set mirrors the f1 and f4 filter positions of the sinc wavelets.
• The Texas Double design reduces tuning effects to a negligible level, and trace-to-trace variations are gradual and consistent.
Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977 G. Partyka (Oct 06)
Well-Log Example - Layering
Sinc Wavelets – high frequency side varies 40 to 100 Hz; low frequency held constant
Raw Layering
6-10-096-100
6-10-066-070
6-10-036-040
Raw Layering
6-10-096-100
6-10-066-070
6-10-036-040
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977
G. Partyka (Oct 06)
Well-Log Example - Layering
10 Hz High-Cut Slope Wavelets – high frequency side varies 40 to 100 Hz; low frequency held constant
Raw Layering
6-10-090-100
6-10-060-070
6-10-030-040
Raw Layering
6-10-090-100
6-10-060-070
6-10-030-040
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977
G. Partyka (Oct 06)
Well-Log Example - Layering
Texas Double Wavelets – high frequency side varies 52 to 112 Hz; low frequency held constant
Raw Layering
6-10-028-112
6-10-021-082
6-10-013-052
Raw Layering
6-10-028-112
6-10-021-082
6-10-013-052
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977
G. Partyka (Oct 06)
Well-Log Example - Layering
Texas Double Wavelets – high frequency side varies 40 to 100 Hz; low frequency held constant
Raw Layering
6-10-025-100
6-10-020-070
6-10-011-040
Raw Layering
6-10-025-100
6-10-020-070
6-10-011-040
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977
G. Partyka (Oct 06)
Well-Log Example - Reflectivity
Sinc Wavelets – high frequency side varies 40 to 100 Hz; low frequency held constant
Raw RC
6-10-096-100
6-10-066-070
6-10-036-040
Raw RC
6-10-096-100
6-10-066-070
6-10-036-040
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977
G. Partyka (Oct 06)
Well-Log Example - Reflectivity
10 Hz High-Cut Slope Wavelets – high frequency side varies 40 to 100 Hz; low frequency held constant
6-10-090-100
6-10-060-070
6-10-030-040
6-10-090-100
6-10-060-070
6-10-030-040
Raw RC
Raw RC
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977
G. Partyka (Oct 06)
Well-Log Example - Reflectivity
Texas Double Wavelets – high frequency side varies 52 to 112 Hz; low frequency held constant
6-10-028-112
6-10-021-082
6-10-013-052
6-10-028-112
6-10-021-082
6-10-013-052
Raw RC
Raw RC
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977
G. Partyka (Oct 06)
Well-Log Example - Reflectivity
Texas Double Wavelets – high frequency side varies 40 to 100 Hz; low frequency held constant
6-10-025-100
6-10-020-070
6-10-011-040
6-10-025-100
6-10-020-070
6-10-011-040
Raw RC
Raw RC
After Designing Optimum Zero-Phase Wavelets, R. S. Kallweit and L. C. Wood, Amoco Houston Division DGTS, January 12, 1977
G. Partyka (Oct 06)