Post on 25-Mar-2018
transcript
Borehole Elemental Concentration
Logs Now Available: A New Source
of Geochemistry Data
Michael Herron, Susan Herron, Jim Grau
Schlumberger-Doll Research
Leaps of Science Follow New
Analytical Capabilities
• Well logging provides more data every day about
earth formations than all laboratory sources in a
year
• Geochemical well logging is a new analytical • Geochemical well logging is a new analytical
capability
• Time for earth scientists to address this new
source of data
ECS Tool and Data Processing Flow
AmBe Source
BGO Crystaland PMT
Boron Sleeve
• Logging Speed:Logging Speed:Logging Speed:Logging Speed: 1800 ft/hr1800 ft/hr1800 ft/hr1800 ft/hr• Vertical Resolution:Vertical Resolution:Vertical Resolution:Vertical Resolution: 1.5 ft1.5 ft1.5 ft1.5 ft• Borehole Fluid:Borehole Fluid:Borehole Fluid:Borehole Fluid: All All All All • Tool Size:Tool Size:Tool Size:Tool Size: 5.0 in O. D.5.0 in O. D.5.0 in O. D.5.0 in O. D.• Length:Length:Length:Length: 6.6 ft6.6 ft6.6 ft6.6 ft• Maximum Temp:Maximum Temp:Maximum Temp:Maximum Temp: 350 350 350 350 ooooFFFF• Maximum Pressure:Maximum Pressure:Maximum Pressure:Maximum Pressure: 20,000 psi20,000 psi20,000 psi20,000 psi• Min Hole Size:Min Hole Size:Min Hole Size:Min Hole Size: 6.00 in6.00 in6.00 in6.00 in
6.6 ft
Boron Sleeve
Electronics
Heat Sink
InternalDewar Flask
AcquisitionAcquisitionAcquisitionAcquisition
Spectral StrippingSpectral StrippingSpectral StrippingSpectral Stripping
SpectroLithSpectroLithSpectroLithSpectroLith
GammaGammaGammaGamma----Ray SpectraRay SpectraRay SpectraRay Spectra
Elemental YieldsElemental YieldsElemental YieldsElemental Yields
Dry Weight ElementsDry Weight ElementsDry Weight ElementsDry Weight ElementsSi, Ca, Fe, S, Ti, GdSi, Ca, Fe, S, Ti, GdSi, Ca, Fe, S, Ti, GdSi, Ca, Fe, S, Ti, Gd
Dry Weight LithologiesDry Weight LithologiesDry Weight LithologiesDry Weight LithologiesClay, Carbonate, Anhydrite, QFMClay, Carbonate, Anhydrite, QFMClay, Carbonate, Anhydrite, QFMClay, Carbonate, Anhydrite, QFM
Oxides ClosureOxides ClosureOxides ClosureOxides Closure
What Do We Measure ?4 MeV neutron interactswith fomation:
Inelastic Interaction(multiple gamma-rays)
Slowing down of neutronthrough multiple scattering
Neutron Capture(multiple gamma-rays)
Gamma-Ray Spectrum
Energy [MeV]
ECS Gamma-Ray SpectrumInelastic and Capture
H
G d
e
0 5 0 1 0 0 1 5 0 2 0 0 2 5 0
In e la s t ic
H
C l
S iF e
Lo
gS
ca
le
Capture Gamma-Ray Spectroscopy
20
40
60
Silic Calci Iron Sulf Titani Gadolin
Relative
Capture Spectra
n
γγγγ
Oxides
0 5
80
100
120
0 2 4 0 1 2 0 1 2 3 0 5 0 1 3
Elemental Concentrations Lithology
Relative
Yields
Elemental Standards
Si
Ca
Fe
S
Oxides
Closure
ECS SpectroLith Dry Weight Lithologies and Elements
200
300
400
500
Open Hole Elemental ConcentrationsD
epth
, ft
0 50
600
700
800
900
Silicon wt%
0 20 40Calcium wt%
0 10 20Iron + .14Al wt%
0 10 20Sulfur wt%
0 2 4Titanium wt%
0 20 40Gadolinium ppm
Depth
, ft
200
400
600
800
Open Hole Lithology
0 50 100
1000
1200
1400
1600
Depth
Clay, wt%0 50 100
Carbonate, wt%0 50 100Quartz-Feld-Mica, wt%
Instant Petrophysical Evaluation
Nuclear spectroscopySLB exclusive hardware SLB exclusive hardware SLB exclusive hardware SLB exclusive hardware
and interpretationand interpretationand interpretationand interpretation
400
600
De
pth
, ft+
Siliciclastics – Four patented applications
800
1000
De
pth
, ft
Lith2.6 3
GDen0.5
Por0.5
Por10
-110
4
Perm Res0 1
Sw
+
=Real-Time Petrophysics
Wireline & LWD
Triple Combo
SDR Fourier Transform Infrared Spectroscopy
Quantitative Mineralogy
• Recognized world-class
• Patented
• Best paper 1997 Society of Core
Analysts
Sample A Qtz Ksp Plag Cal Mg-Cal Dol Sid Py Kaol 2:1 Al clay 2:1 Fe clay Fe-Chl
Actual 25 5 5 5 0 0 0 0 15 20 20 5
Texaco 26 4 3 5 0 0 0 0 16 19 22 5
Vendor 1 68 3 4 5 0 0 0 0 8 0
Vendor 2 44 1 5 2 0.1 0 0.1 23 11
Vendor 3 41 2 3 9 0 0 0 0 36 0
Sample B Qtz Ksp Plag Cal Mg-Cal Dol Sid Py Kaol 2:1 Al clay 2:1 Fe clay Fe-Chl
Actual 30 5 10 5 0 5 0 5 20 10 0 10
Texaco 31 2 8 4 0 4 0 3 21 13 0 10
Vendor 1 56 0 7 3 0 6 0 14 12 1
11
12
9
2
Commercial XRD and Actual Mineralogy
Vendor 1 56 0 7 3 0 6 0 14 12 1
Vendor 2 34 1 8 3 0 6 0 4 24 18
Vendor 3 52 2 3 13 0 0 0 2 24 0
Sample C Qtz Ksp Plag Cal Mg-Cal Dol Sid Py Kaol 2:1 Al clay 2:1 Fe clay Fe-Chl
Actual 30 10 5 5 5 5 10 0 10 15 0 5
Texaco 30 8 4 5 5 4 10 0 10 16 0 5
Vendor 1 63 3 14 3 0 5 6 0 5 0
Vendor 2 39 2 6 4 0 7 14 0.2 15 10
Vendor 3 37 1 2 8 0 9 19 0 19 0
2
2
5
1
4
5
D. McCarty (Chevron)
Sample A Qtz Ksp Plag Cal Mg-Cal Dol Sid Py Kaol 2:1 Al clay 2:1 Fe clay Fe-Chl
Actual 25 5 5 5 0 0 0 0 15 20 20 5
Texaco 26 4 3 5 0 0 0 0 16 19 22 5
Vendor 1 68 3 4 5 0 0 0 0 8 0
Vendor 2 44 1 5 2 0.1 0 0.1 23 11
Vendor 3 41 2 3 9 0 0 0 0 36 0
Sample B Qtz Ksp Plag Cal Mg-Cal Dol Sid Py Kaol 2:1 Al clay 2:1 Fe clay Fe-Chl
Actual 30 5 10 5 0 5 0 5 20 10 0 10
Texaco 31 2 8 4 0 4 0 3 21 13 0 10
Vendor 1 56 0 7 3 0 6 0 14 12 1
11
12
9
2
Commercial XRD and Actual Mineralogy
Vendor 1 56 0 7 3 0 6 0 14 12 1
Vendor 2 34 1 8 3 0 6 0 4 24 18
Vendor 3 52 2 3 13 0 0 0 2 24 0
Sample C Qtz Ksp Plag Cal Mg-Cal Dol Sid Py Kaol 2:1 Al clay 2:1 Fe clay Fe-Chl
Actual 30 10 5 5 5 5 10 0 10 15 0 5
Texaco 30 8 4 5 5 4 10 0 10 16 0 5
Vendor 1 63 3 14 3 0 5 6 0 5 0
Vendor 2 39 2 6 4 0 7 14 0.2 15 10
Vendor 3 37 1 2 8 0 9 19 0 19 0
2
2
5
1
4
5
D. McCarty (Chevron)
True and Estimated Mineral Concentrations
0
5
10
Quartz Opal-A Ortho. Olig. Calcite Dolomite Pyrite
True CompositionEstimated from FT-IR
0 50 100
15
20
25
30
35
40
45
Sa
mp
le
1.230 50 100
1.100 50
0.570 50
1.060 50 100
0.950 50 100
1.730 50
0.07
True and Estimated Mineral Concentrations
0
5
10
Illite Smec. Kaol. Chlor. Musc. Glauc.Biotite
True CompositionEstimated from FT-IR
0 50
15
20
25
30
35
40
45
Sam
ple
1.600 50
1.080 50
0.570 50
0.970 50
0.570 50
0.660 50
0.13
Development of Applications
• Total clay from chemical data
• Matrix density from chemical data
• More for you to develop• More for you to develop
Clay and Gamma Ray
0
50
100
Cla
y w
t%Well 1 Well 2 Well 3 Well 4
50
100
Cla
y w
t%
Well 5 Well 6 Well 7 Well 8
0
50
Cla
y w
t%
0 100 2000
50
100
Cla
y w
t%
Gamma Ray
Well 9
0 100 200Gamma Ray
Well 10
0 100 200Gamma Ray
Well 11
0 100 200Gamma Ray
Well 12
0 10 200
50
100
Cla
y w
t%
Thorium ppm0 5 10
Uranium ppm0 2.5 5
Potassium wt%
100
Cla
y w
t%
Clay Elemental Relationships - Well 3
0 10 200
50
Cla
y w
t%
Aluminum wt%0 1 2
Titanium wt%0 5 10
Gadolinium
0 25 500
50
100
Cla
y w
t%
Silicon wt%0 15 30
Iron wt%0 20 40
Calcium wt%
Clay Elemental Relationships - Well 5100
0 10 200
50
100
Cla
y w
t%
Thorium ppm0 5 10
Uranium ppm0 2.5 5
Potassium wt%
50
100
Cla
y w
t%
0 10 200
50
Cla
y w
t%
Aluminum wt%0 1 2
Titanium wt%0 5 10
Gadolinium
0 25 500
50
100
Cla
y w
t%
Silicon wt%0 15 30
Iron wt%0 20 40
Calcium wt%
100
Clay Elemental Relationships - Well 6
0 10 200
50
100
Cla
y w
t%
Thorium ppm0 5 10
Uranium ppm0 2.5 5
Potassium wt%
50
100
Cla
y w
t%
0 10 200
50
Cla
y w
t%
Aluminum wt%0 1 2
Titanium wt%0 5 10
Gadolinium
0 25 500
50
100
Cla
y w
t%
Silicon wt%0 15 30
Iron wt%0 20 40
Calcium wt%
Aluminum and Clay100
Cla
y w
t%C
lay w
t%
0
50
100
Cla
y w
t%
Well 1 Well 2 Well 3 Well 4
50
100
Cla
y w
t%
Well 5 Well 6 Well 7 Well 8
Cla
y w
t%C
lay w
t%
0
Cla
y w
t%
0 10 200
50
100
Cla
y w
t%
Aluminum wt%
Well 9
0 10 20Aluminum wt%
Well 10
0 10 20Aluminum wt%
Well 11
0 10 20Aluminum wt%
Well 12
Estimation of Aluminum
0
10
20
Alu
min
um
wt%
Well 1 Well 2 Well 3 Well 4
10
20
Alu
min
um
wt%
Well 5 Well 6 Well 7 Well 8
0
Alu
min
um
wt%
0 10 200
10
20
Alu
min
um
wt%
Aluminum Emulator
Well 9
0 10 20Aluminum Emulator
Well 10
0 10 20Aluminum Emulator
Well 11
0 10 20Aluminum Emulator
Well 12
SpectroLith Clay from Si, Ca, Fe
0
50
100
Cla
y w
t%
Well 1 Well 2 Well 3 Well 4
50
100
Cla
y w
t%
Well 5 Well 6 Well 7 Well 8
0
50
Cla
y w
t%
0 50 1000
50
100
Cla
y w
t%
Estimated Clay
Well 9
0 50 100Estimated Clay
Well 10
0 50 100Estimated Clay
Well 11
0 50 100Estimated Clay
Well 12
Changes in ρma with Silicon
2.6
2.8
3
3.2
3.4
3.6M
atr
ix D
ensity,
g c
m-3
Silicon, wt %
0 20 402.6
Variation of ρma with Calcium
2.6
2.8
3
3.2
3.4
3.6
2.6
2.8
3
3.2
3.4
3.6M
atr
ix D
ensity,
g c
m-3
0 20 402.6
Calcium, wt %Silicon, wt %
0 20 402.6
ρma Increases with Iron
2.6
2.8
3
3.2
3.4
3.6M
atr
ix D
ensity,
g c
m-3
2.6
2.8
3
3.2
3.4
3.6
0 20 402.6
2.8
3
3.2
3.4
3.6
Iron, wt%
Matr
ix D
ensity,
g c
m-3
Silicon, wt %
0 20 402.6
0 20 402.6
Calcium, wt %
ρma Also Increases with Sulfur
2.6
2.8
3
3.2
3.4
3.6M
atr
ix D
ensity,
g c
m-3
2.6
2.8
3
3.2
3.4
3.6
0 10 20 302.6
2.8
3
3.2
3.4
3.6
Sulfur, wt%
Silicon, wt %
0 20 402.6
0 20 402.6
Calcium, wt %
0 20 402.6
2.8
3
3.2
3.4
3.6
Iron, wt%
Matr
ix D
ensity,
g c
m-3
Density of Common Iron-bearing Minerals
4.5
5.0
5.5G
rain
density,
g c
m-3
Pyrite
Hematite
0 20 40 60 802.5
3.0
3.5
4.0
Iron concentration, wt %
Gra
in d
ensity,
g c
m
Illite
Quartz
Glauconite
Chlorite
Siderite
Regression Results
ρma = 2.620
+ 0.0490 Si
Non-arkose & Subarkose
+ 0.0490 Si
+ 0.2274 (Ca + 0.6 Na)
+ 1.993 (Fe + 0.14 Al)
+ 1.193 S
r = 0.967; std error 0.015 g cm-3
Measured vs Computed Density
2.8
3
aad = 0.012 aad = 0.026
Estim
ate
d fro
m e
lem
en
ts
aad = 0.01
Non-arkose Subarkose
2.6
2.6
2.8
3
Estim
ate
d fro
m e
lem
en
ts
aad = 0.0074 aad = 0.009
2.6 2.8 3
Matrix density from minerals
aad = 0.005
2.6 2.8 3 2.6 2.8 3
XX100
Dep
th, ft
Clay
QFM
Carbonate
Gamma ray
Pyrite
a b c ed
0 150
0 1
XX300
XX500
Dep
th, ft
Lithology, wt fraction
00.20.4
Porosity, pu
100
101
102
103
Permeability, md
100
101
102
R0 ohm-m
0 1
SW
XX100
Clay
QFM
Carbonate
Pyrite
ca b
DRFT-IR Clay
XRD Clay
Clay
QFM
Carbonate
Pyrite
0 150
XX300
XX500
Dep
th, ft
Gamma Ray, API
0 1
Lithology, wt fraction
0 1
Lithology, wt fraction
0 500
50
Co
re, w
t%
Silicon
a
0 20 400
20
40
Calcium
b
0 5 100
5
10
Iron
c
0 50
5
Potassium
d
0 5 10 150
5
10
15
Co
re, w
t%
Aluminum
e
0 5 100
5
10
Reconstructed, wt%
Sulfur
f
0 50
5
Sodium
g
0 5 100
5
10
Magnesium
h
60
80
100
To
tal C
lay,
wt
%
a
60
80
100
b
0 50 100 150 2000
20
40
Gamma Ray (API)
To
tal C
lay,
wt
%
0 5 10 150
20
40
0.39 (100 – SiO2 – CaCO3 – 1.99 Fe)
Clay
QFM
Carbonate
Pyrite
Oil
Free Water
Irreducible Water
Clay
QFM
Carbonate
Pyrite
Oil
Free Water
Irreducible Water
XX100
a b
XX300
XX500
Dep
th, ft
0 1
Formation, vol fraction
0 1
Formation, vol fraction
Well-to-Well Gamma Ray-Resistivity
Sometimes these
Correlations are
Difficult to understanDifficult to understan
And not repeatable
0 50 100 150Gamma Ray (API)
0 50 100 150Gamma Ray (API)
Shape
Similarity
Ambiguous Correlations with Gamma Ray
Depth
(ft
)
Well 1 Well 2
Ambiguous Correlations with Gamma Ray
0 50 100 150
Gamma Ray (API)
0 50 100 150
Gamma Ray (API)
? Shape
Similarity
Depth
(ft
)
Well 1 Well 2
0 10 20 30 40
Calcium (wt %)0 10 20 30 40
Calcium (wt %)
Shape
Similarity
Chemostratigraphy Lowers Ambiguity
Depth
(ft
) Similarity
&
Absolute
Value
Well 1 Well 2
This is the Chemostratigraphy Connection
Ca Connections
0 10 20 30 40 50Silicon (wt %)
0 10 20 30 40 50Silicon (wt %)
Si Connections
Depth
(ft
)
3
Well 2Well 1
Leaps of Science Follow New
Analytical Capabilities
• Induced gamma ray spectroscopy is now
becoming a standard oilfield service
• More data in an hour than in a lab geochemist’s
lifetimelifetime
• New elements are around the corner
• Challenge is on Academia and Industry to
maximize use of these new data