Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori...

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Malek Elgmati Hao Zhang Baojun Bai Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

Transcript of Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori...

Page 1: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

Malek Elgmati  Hao Zhang  Baojun Bai  Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu

SPE Americas Unconventional Gas Conference and Exhibition 

12–16 June 2011

Page 2: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

T lk O tliTalk OutlinesUS Natural Gas Shale ImportanceUS Natural Gas Shale ImportanceResearch Scope & WorkflowMICP ResultsSubmicron Pore Imaging & Reconstructiong gXRD Clay Mineralogy ResultsShale Gas Wettability ResultsShale Gas Wettability ResultsConclusionsAcknowledgments

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Page 3: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

US Natural Gas Importance87% of the supplied NG in US was produced domestically (EIA, 2009).US possesses 2,552 Tcf of potential NG (EIA , 2011)Shale gas est  reserve represent 32 4% Shale gas est. reserve represent 32.4% 

Utica

Fayetteville

Haynesville3

Page 4: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

Essential Shale Gas ParametersEssential Shale Gas ParametersDemystifying Shale Gas

Gas-In-Place

PermeabilityMaturation

Demystifying Shale Gas Complexity by…

PetrophysicsPalynology

Geology

Shale Gas Productivity ThicknessOrganic

RichnessMaterial Science

Pore pressureMineralogy

Sh l  G   BrittlenessShale Gas Characterization 

Interdisciplinary Tools4

Page 5: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

R h Obj tiResearch Objectives

Look into the submicron pore structure of shale gas to extract the petrophysical properties.

Determine the potential effects of organic matter, rock mineralogy on pore types and permeability.

Identify shale gas porosity types with their magnitudes.

Measure the impact of fracturing fluids on shale gas wettability.y

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Page 6: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

Shale Gas Submicron Pore Analysis Workflow

Shale Gas

6   D G  Fl  M d liy

6. 3D Gas Flow Modeling

1. Mercury Porosimetry

5. Kerogen Analysis

2. Contact 3  FIB/SEM Angle 

Measurements 

3. FIB/SEM Submicron Imaging4. XRD/Clay 

Mineralogy

Element 

3D  pore reconstruction 

analysis

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Page 7: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

MICP Results‐Utica Shale Various pore sizes 

0.002 106,663

), µ

m Drainage

Imbibition

Various pore sizes and/or different flow units.

0.02

0.2 1,067

10,666

Dia

me

ter

(dp)

su

re,

psi

Imbibition

Major intrusion between 2,000 and 

  i

2 107

,

uiv

ale

nt

Po

re

Pre

s

Min. dp = 15 nmMax. dp = 15 µmMedian dp = 30 nmTotal ϕ = 14 56%

20,000 psi Eq. dp= 20−200 nm  Median d  30 nm

20 11020406080100

Eq

u

Mercury Saturation, SHg %

Total ϕ = 14.56%Avg.(k) = 4.15x10-3 md Median dp= 30 nm

φ = 14.5% k 4 15  micro darcyy , Hg k =4.15  micro‐darcy Resi. Hg is 23.3%

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Page 8: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

MICP Results‐Haynesville Shale

One morphology is present.

0.002 106,663

, µ

m

Drainage

Imbibition

Major intrusion between 10,600 and 60 000 psi

0.02

0.2 1,067

10,666

Dia

me

ter

(dp),

ure

, p

si

Min. dp = 4 nmMax. d = 15 µm 60,000 psi

Eq. dp= 2−20 nm  Median d = 6 5 nm

0.2

2 107

1,067

vale

nt

Po

re D

Pre

ssu Max. dp 15 µm

Median dp = 6.5 nmTotal ϕ = 10.34%Avg.(k) = 1.38x10-4 md

Median dp= 6.5 nm φ = 10 % k=138 nano‐darcy

20 11020406080100

Eq

ui

Mercury Saturation, SHg %

SHg = 34.64%

k=138 nano darcy Resi. Hg = 26.66%

Mercury Saturation, SHg %

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Page 9: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

SEM‐FIB Tomography: 3D SubmicronSEM‐FIB Tomography: 3D Submicron Pore‐Scale Reconstruction

Sample preparation In‐situ  specimen 

Dual ‐beam

Slicing

In situ  specimen preparation

Acquire 200 slices  f    hi k of 50nm thick 

Imaging processing programs.programs.

2D Kerogen model 3D Structured pore model

2D Kerogen 3D Pore Model9

Page 10: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

SEM Images of Utica Shale Sample No. 3

Intergranular pore sizes ranged from  t    

A

15 to 50 nm.Intraparticular or mineral porosity mineral porosity with opening throat is about 5 

B

5nm.

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Page 11: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

f i h l lSEM Images of Utica Shale Sample No. 2AA

Clay platelets within the quartz grains which create inextricable pore structure with a variety of pore structure with a variety of pore sizes due to diagenesis. 

B ‐ Organic matter with a complex textile of porespores.‐Morphology and genesis of OM control th   bilit  the permeability pathways of gas flow .

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Page 12: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

/SE/BSE Images of Utica Shale Sample No. 2C

AA

C

B

‐ Nano‐porosity is observed within pyrite framboids.

B

‐ Pore sizes of 20 and 100 nm. 

B

Clay platelets are closely packed together and form a variety of micron and nanoypores (< 2 µm in diameter)

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Page 13: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

SEM Images of Fayetteville Shale Sample(A) V Mi it  (B) K N it  O i   b t (A) Vuggy Micro‐porosity, (B) Kerogen Nano‐porosity Occupies about 40−50% of the Organic Matter, and (C) Nano Fractures

A B C

B

C

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Page 14: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

3D V l P Si Hi t3D Volume Pore Size Histogram Major pore size is 30nm Major pore size is 30nm Few micron‐cracks or vugs of 3 μm. φT t l = 28%  k = 0 01 mdφTotal = 28%, kav. = 0.01 md

(A) (B)

2500

3000Min. dp = 27 nmMax. dp = 4.33 µmMean = 40 nmT t l ϕ 28 22%

1500

2000

of E

lem

ents

Total ϕ = 28.22%Kerogen ϕ = 11.29 %Tortuosity (τ) = 1.44Anisotropy (β) = 0.28Avg. perm. (k) = 0.01 mdkh = kx= ky = 0.018 mdkv = kz = 0.005 md

500

1000No.

o kv kz 0.005 md

φOM = 11.3% 1.44 tortuosity

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09 0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9 1 2 3 4 5 6 7 8 9 10

Mor

e

Equivalent Pore Diameter (dp), µm

0.28 anisotropy14

Page 15: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

XRD Clay Mineralogy Results

Semi‐quantitative clay minerals analysis y

Haynesville & Utica‐Indian Castle Fm. have illite%

Utica‐Dolgeville Fm. exhibits high calcite%F ill   i i ll   Fayetteville  compositionally comprise of high quartz% 

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Page 16: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

Shale Gas WettabilityShale Gas Wettability Six fracturing fluidsg

‐ 2 Polymers‐ 4 Surfactants%  ie) 70

80

90

Haynesville Shale (12,000ft)

0.1% concentrations Polished surfaces For 7.5 minutesA

ngle

(Deg

re

40

50

60

70

For 7.5 minutes Results compared to DIW 

Con

tact

0

10

20

30

Haynesville becomes hydrophobic with polymers and Flow‐back surfactant.70% illite content

0 100 200 300 400 5000

Tim e (Second)

Surfactants makes all shaleshydrophilic (strongly water‐wet)

7Low TOC 0.81 wt.%

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Page 17: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

Utica Shale Dolgeville FmUtica Shale‐Dolgeville Fm.)

8 0

9 0

U tic a S h a le /D o lg e v ille (4 8 7 8 f t) High contact angle near 

t Ang

le (D

egre

e

4 0

5 0

6 0

7 0 oil‐wet (60‐80) High calcite content %TOC 0.31 wt.%

0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0

Con

tact

0

1 0

2 0

3 0

FRW‐18 polymer slightly impairs surface wettability t d  t t 0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0

6 0

7 0

8 0

9 0

U tic a S h a le /D o lg e v il le (5 ,1 9 7 f t)

Deg

ree)

toward water‐wet .

2 0

3 0

4 0

5 0

Con

tact

Ang

le (D

FRW‐18 & 20 resulted in similar impairment to intermediate water wet

TOC 1.12 wt.%

T im e (S e c o n d )0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0

0

1 0

C intermediate water‐wet

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Page 18: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

Utica‐Indian Castle Fm./Fayetteville Shale

Both shales’ have 90

U ti S h l /I d i C tl (4649ft)

Utica Indian Castle Fm./Fayetteville Shale

Both shales have similar wettability trends.50

60

70

80U tica S hale /Ind ian C astle (4649ft)

Ang

le (D

egre

e)

TOC 1.31 wt.%

High illite content% Low TOC content%10

20

30

40

Con

tact

High quartz or ibl  illi

0 100 200 300 400 5000

gree

)

7 0

8 0

9 0F a y e t te v i l le S h a le (2 3 5 1 f t )

possibly illite High TOC content%

Con

tact

Ang

le (D

eg

2 0

3 0

4 0

5 0

6 0 TOC 4.04 wt.%

T im e (S e c o n d )0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0

C

0

1 0

2 0

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Page 19: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

Conclusions

Haynesville shale exhibited extremely low matrix permeability with a pore size of 2−20 nm, φ=10%.

Utica shale offered better matrix permeability, with a pore throat size of 20−200 nm, φ=14.5%.

ill   h l   l d i   h  hi h  k   d  Fayetteville shale resulted in the highest k=0.01 md and φ=28%.Th   i   tt   f F tt ill   h l  h   The organic matter of Fayetteville shale has abundance of nanopores with size of 5−100 nm and occupy 40‐50% of the kerogen bodyand occupy 40‐50% of the kerogen body.

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Page 20: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

A robust  detailed sequential milling and imaging 

Conclusions (cont.) A robust, detailed sequential milling and imaging procedure using SEM‐FIB proved successful.

Various types of porosities (e g  interparticular  Various types of porosities (e.g., interparticular, intergranular, kerogen, vuggy, pyrite framboids, and fractures) were observed.

Numerous petrophysical properties were extracted from reconstructed 3D submicron pore model. 

Calcite content proved the dominant factor changing the wettability of shale gas rock to oil‐wet.

Organic matter content governed the wettability alterations of calcareous samples. 20

Page 21: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

Acknowledgments

Dr. Timothy Kneafsey (BNL)  Materials Research Center (Missouri S&T) Southwestern Energy  Baker‐Hughes Co. RPSEA & DOE

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Page 22: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

Thank YouQuestions?Q

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Page 23: Malek Elgmati, Hao Zhang, Baojun Bai, Qi Qu · Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu SPE Americas Unconventional Gas Conference and Exhibition 12–16 June 2011

Malek Elgmati  Hao Zhang  Baojun Bai  Malek Elgmati, Hao Zhang, Baojun Bai, Ralph Flori and Qi Qu

SPE Americas Unconventional Gas Conference and Exhibition 

12–16 June 2011