KMS Technologies – KJT Enterprises Inc.

Mirotchnik, K., Kryuchkov, S., Strack, K. – M.

A novel method to determine NMR petrophysical parameters from drill

cuttings

2004

Presentation

Transaction of the Society of Petrophysicists and Well Log Analysts, Annual Symposium, 45, MM

SPWLA 2004

A novel method A novel method

to determine to determine

NMR NMR petrophysicalpetrophysical parameters parameters

from drill cuttingsfrom drill cuttingsSPWLA 2004, The NetherlandsSPWLA 2004, The Netherlands

K. Mirotchnik(1), S. Kryuchkov(1), K. Strack(2)

(1) NMR Plus Inc. Calgary(2) KMS Technologies – KJT Enterprises Inc., Houston

SPWLA 2004

NMR NMR parmsparms from cuttingsfrom cuttings

• Motivation• Determining cutting size• Estimating porosity• Estimating permeabilities• Summary & outlook

SPWLA 2004

OutlineOutline

• Motivation• Determining cutting size• Estimating porosity• Estimating permeabilities• Summary & outlook

SPWLA 2004

NMR measurementsNMR measurements

• Have become a great contribution to medical science

• Allow petrophysical parameter derivations:⌦Logs (WL and LWD)⌦Cores

• Why not extend to low cost environments?

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The trick in this presentationThe trick in this presentation……

• Take the measurements from the borehole back to the lab = mud logging cabin

• Improved hardware, tightly couple acquisition w/ hardware and focus on application

• Derive special petrophysical models for automated interpretation.

SPWLA 2004

NMR parameter from cores NMR parameter from cores vsvs cuttingscuttings

Cores pro:• Accurate NMR parameter estimation• Work done in laboratory under controlled condition

Cores con:• Characterizes only selected part of well• Characterization after drilling• Turn around time• Cost

SPWLA 2004

Why Why NMR parameters from drill cuttings?NMR parameters from drill cuttings?In the past:• Small particles of cuttings – small signal –impossible to separate signal from noise• Sample preparation took too much time for well site applications

Suggested solution:• New tool has high signal-to-noise ratio >200• Optimized workflows include preparation, measurement and interpretation procedures.•Reduce turn-around time•Reduce cost

SPWLA 2004

Technology development processTechnology development process

• Market evaluation• Feasibility study w/ cutting from 1 to 6.35 mm• Pilot experiments with solid samples and synthetic

cuttings• Pilot measurements (Canada, Russia, US and China)

Results:• Automated process integrated into one instrument

SPWLA 2004

OutlineOutline

• Motivation• Determining cutting size• Estimating porosity• Estimating permeabilities• Summary & outlook

SPWLA 2004

ProcessProcess to find cutting size rangeto find cutting size range

1. Obtain known rock samples 2. Plugs: determine total porosity,

permeability and Swirr with direct methods.

3. Measure NMR parameters (Sw=100%)4. Use similar samples for synthetic cuttings5. Measure NMR parameters (Sw=100%)6. Compare plug & cuttings results7. Also group by filtration radius & grain size

SPWLA 2004

Cumulative relaxation timeCumulative relaxation timeBerea SS (cores & cuttings).Berea SS (cores & cuttings).

0

0.2

0.4

0.6

0.8

1

1.00 10.00 100.00 1000.00

Relaxation Time, ms

Rev

ativ

e am

plitu

de

Berea, plug-1Berea, plug1-minBerea, plug1-maxBerea plug-2

Cores

0.000

0.200

0.400

0.600

0.800

1.000

1.00 10.00 100.00 1000.00

Relaxation Time, ms

Rev

ativ

e am

plitu

de

Berea, Cuttings 1.0-3.35 mmBerea, Cuttings 1.0-3.35 mm-minBerea, Cuttings 1.0-3.35 mm-max

Cuttings 1 – 3.35 mm

0

0.2

0.4

0.6

0.8

1

1.00 10.00 100.00 1000.00

Relaxation Time, ms

Rev

ativ

e am

plitu

de

Berea, Cuttings 3.35-6.35 mmBerea, Cuttings 3.35-6.35 mm-minBerea, Cuttings 3.35-6.35 mm-max

Cuttings 3.35-6.25 mm

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OutlineOutline

• Motivation• Determining cutting size• Estimating porosity• Estimating permeabilities• Summary & outlook

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Porosity determinationPorosity determination

• Most critical parameter is volume determination

• Determine hydrogen volume from weight/porosity measurements

• Compare with NMR measurements• Repeat for light & heavy oil saturations

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y = 0.939x + 0.215R2 = 0.9514

2.50

3.00

3.50

4.00

4.50

2.5 3 3.5 4 4.5

V_H by weight, cm3

VH

NM

R, c

m3

0

1

2

3

4

5

6

1 4 7 10 13 16 19 22 25 28 31 34 37 40

M ode l Numbe r

A B

Hydrogen volume: weight versus NMRHydrogen volume: weight versus NMR

Perfect fit

SPWLA 2004

Porosity by Archimedes vs. NMR Porosity.Porosity by Archimedes vs. NMR Porosity.

Porosity Arch vs POR- NMR (NNLS)

y = 0.9984x + 0.2249R2 = 0.9731

10.0

15.0

20.0

25.0

10.0 15.0 20.0 25.0

Porosity Arch, %

Poro

sity

(NM

R),

%

POR-TE=0.3 m s)

SPWLA 2004

Biggest error sourcesBiggest error sources

• Accurate volume measurement

Porosity error• ± 1.2 % literature (Kenyon, 1992; Vinegar, 1995, Coates et al., 1999)

• Approx. 1% NMR from cuttings

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OutlineOutline

• Motivation• Determining cutting size• Estimating porosity• Estimating permeabilities• Summary & outlook

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ProcessProcess

• Determine Perm using standard models (i.e. Mean T2Model; Free Fluid Model)

Lg(PERM) =a * Φeff + b

Pore size distrubition and grain size dependent

Where a, b are constants Khannin (1976)

We based our values for filtration radii between 5 and 2 µm and rock type (172 samples)

SPWLA 2004

Verification of permeability modelsVerification of permeability models• Models from samples from 6 fields• Samples from different saturations

water, oil +Swirr, water+ Soil_res. • Oils saturated samples contained

hydrocarbons with Visc<20cPs.• The pore surface wettability was water wet,

mixed and non-water wet.

SPWLA 2004

Basics of Basics of MRMR--MLML™™ ModelModel

Four models were developed:

PERM= a* ∅eff + ba and b – Gs dependant coefficients

a4, b4very fine0.01-0.05Siltstone4

a3, b3fine0.05-0.1Siltstone3

a2, b2medium0.1-0.25Sandstone2

a1, b1coarse0.25-0.5Sandstone1

a, bGradeGrain size, mm

Lithology

SPWLA 2004

Perm results comparisonPerm results comparison

Sample/cutting K*, mD Meff_min,

% Meff_max,

% Kmin, mD Kmax,

mD Cuttings size, mm Sample Berea-1 38 9.6 13.1 18 70 Sample Berea-2 70.5 12 14 45 100 Cutting Berea 38-70.5 9.2 13.5 15 80 3.3 – 6.3 Cutting Berea 38-70.5 7.3 10.8 7.5 30 1.0 – 3.3 Sample FCR 12.7 8.3 11.1 10 32 Cutting FCR 12.7 6.8 10.2 6 22 3.3 – 6.3 Cutting FCR 12.7 7.5 11.4 8 35 1.0 – 3.3

DirectPerm

PorosityMin. Max. Cutting

Size

NMR PermMin. Max.Core

SPWLA 2004

PERM results comparisonPERM results comparison

y = 0.874x0.9354

R2 = 0.9278

0.1

1

10

100

1000

10000

0.1 1 10 100 1000 10000

PERM_direct, mD

Perm

_cr3

, mD

Set 1 Set 2

Set 3 Set 4

Set 5 Set 6

Equality

Perfect fit

SPWLA 2004

Perm comparisonPerm comparison

0.1

1

10

100

1000

0.10 1.00 10.00 100.00 1000.00

PERM-direct, mD

PERM

-NM

R_Co

ates

K3max

1.0

10.0

100.0

1000.0

1.00 10.00 100.00 1000.00

Perm-direct, mDPe

rm_M

3_m

in, m

D

A B100% water saturation Water & oil mixed

SPWLA 2004

OutlineOutline

• Motivation• Determining cutting size• Estimating porosity• Estimation permeabilities• Summary & outlook

SPWLA 2004

Results from ChinaResults from China

Permeability NMR Kenyon vs Permeability from Customer

1.00E-06

1.00E-05

1.00E-04

1.00E-03

1.00E-02

1.00E-01

1.00E+00

1.00E+01

1.00E-06 1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 1.00E+01

Permeability from Customer (mD)

Perm

eabi

lity

NM

R K

enyo

n (m

D)

Porosity NMR vs Porosity from Customer y = 1.0997x + 0.812R2 = 0.8977

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Porosity from Customer (% )

Poro

sity

NM

R (%

)

SPWLA 2004

Results from SiberiaResults from SiberiaPorosity Arch vs POR- NMR (NNLS)

y = 0.9984x + 0.2249R2 = 0.97

10.0

15.0

20.0

25.0

10.0 15.0 20.0 25.0

Porosity Arch, %

Poro

sity

(NM

R),

%

POR-TE=0.3 ms)

PERM determination acco rding to Crite rion 3

y = 0.874x0.9354

R2 = 0.9278

0.1

1

10

100

1000

10000

0.1 1 10 1 00 1000 10000

PERM_direct, mD

Perm

_cr3

, mD

Set 1 Set 2

Set 3 Set 4

Set 5 Set 6

Equality

SPWLA 2004

ConclusionConclusion

• Porosity, permeability can be determined from drill cutting > 1mm for clastics

• Carbonates require reservoir specific fine tuning of the model.

• Measuring the NMR parameters at the well site is a large cost saving

• As experience with the method increases, we can address other NMR parameters also.

SPWLA 2004

AcknowledgementsAcknowledgements

• Canadian government for funding

KMS Technologies – KJT Enterprises Inc. 6420 Richmond Ave., Suite 610

Houston, Texas, 77057, USA Tel: 713.532.8144

info@kmstechnologies.com

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