Borehole Elemental Concentration Logs Now Available: … Petrophysics Wireline & LWD Triple Combo...

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)

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%


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


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%


50

100

Cla

y w

t%


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%


10

20

Alu

min

um

wt%


0

Alu

min

um

wt%

0 10 200

10

20

Alu

min

um

wt%

Aluminum Emulator

Well 9

0 10 20Aluminum Emulator

Well 10


Well 11


Well 12

SpectroLith Clay from Si, Ca, Fe

0

50

100

Cla

y w

t%


50

100

Cla

y w

t%


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


Well 11


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


0 1


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

Borehole Elemental Concentration Logs Now Available: … Petrophysics Wireline & LWD Triple Combo...

Documents

Transcript of Borehole Elemental Concentration Logs Now Available: … Petrophysics Wireline & LWD Triple Combo...