EPA Hydraulic Fracturing Workshop

March 10th- 11th, 2011
2

“Fracture Design in Horizontal 

Shale Wells – Data Gathering 

to Implementation”

Tim Beard

Sr. Engineering Advisor - Completions

Chesapeake Energy Corporation

6100 N. Western Avenue ı Oklahoma City, OK 76118 ı 405-935-8000

AskChesapeake@chk.com ı chk.com ı NYSE: CHK
3

Presentation Overview

Goal

Planning

• Data

• Measuring

• Validating

• Properties Needed in Modeling

• Designing the Hydraulic Fracture

• Frac Models in Vertically 

Heterogeneous Formations

Execution
4

CHK’s Operating Areas

Low-risk, U.S. onshore asset base; Not exposed to economic, geopolitical or 

technological risks internationally or in the Gulf of Mexico
5

Shale Information

Shale Play Fayetteville Barnett Eagle Ford Haynesville Marcellus

Average Depth From 

Surface (ft)

4,500 7,400 9,000 11,500 7,100

Bottom Hole 

Temperature (F)

130 190 260 320 145

Bottom Hole 

Pressure (psi)

2,000 2,900 6,200 10,000 4,600
6

What is the Goal of Hydraulic Fracturing?

Maximize the Stimulated Reservoir Volume (SRV) 

along the horizontal wellbore for a given well 

spacing to maximize hydrocarbon production within 

the zone of interest.

Orientation and lateral length

Vertical placement within flow unit

Rock Properties/Mechanics

Stages/Perf Clusters/Isolation

Fluid and proppant selection
7

Planning
8

What data do we use?

What are the main variables that need 

to be factored into each frac design?

• Porosity and Permeability

• Lateral Length

• Brittleness vs. Ductility

• Young’s Modulus

• Poisson’s Ratio

• Fracture Toughness

• Thickness

• Barriers

• Depth

• In-Situ Stress

• Maximum Principle 

Stress Direction

• Lithology of Pay

• Stress Anisotropy

• Natural Fractures

• Gas or Liquids Reservoir

• Temperature

• Reservoir Pressure
9

Wireline Log Data

Logs are run in regionally representative pilot wells over the 

zone(s) of interest.

Triple Combo Log, Spectral Gamma Ray, Dipole Sonic Log, Formation 

MicroImager

The data gathered from the logs is utilized to do a 

petrophysical analysis and to calculate the rock mechanical 

properties of the reservoir to determine pay intervals, barriers, 

etc.

FMI and multi-caliper log data are also used to determine a 

maximum and minimum principle stress direction and to 

determine if there are natural fractures present.
10

Lateral Orientation 

Maximum Principle Stress Direction

Lateral Placement

● Perpendicular to maximum principle stress 

● Optimize transverse fracturing 

● Slight variations for more efficient pattern 

development 
11

Well: PROCKO_MARTIN_WHITMAN_625599

DATE PLOTTED: 27-Oct-2008

HORIZONTAL UNITS: FEET

Y COORDINATE: 14416529.67

X COORDINATE: 1745180.06

LONGITUDE: 80.0000

LATITUDE: 39.0000

LOCATION: TWP - Range - Sec

COMPANY: CHK

VERTICAL SCALE: 1:240

DATE LOGGED: 31-Jul-2007

VERTICAL UNITS: FEET

DRILLED DEPTH: 7780.00

ELEVATION MEAS. REF.: -

MEASUREMENT REF.: 

SURFACE ELEVATION: 15.00

DATUM FOR ELEVATION: GR

RM

- @ -

RMC

- @ -

RMF

- @ -

DFD

-

DEPTH (FEET) BHT

7120.00-7429.00

SHT BIT SIZE

Composite

- -

-

bs

6 IN 16

HCAL_1

4 IN 24

DCAL_1

0 IN 10

TOTAL_GAMMA_1

0 GAPI 200

GR_1

0 GAPI 200

HDRA_1

0.75 G/C3 -0.25

7150

7200

7250

7300

7350

7400

7120.0

7429.0

DEPTH

FEET

209.0 RESERVOIR_INT.NET PERFS.PERFS TREATMENT.STAGE

RXO8_1

0.2 OHMM 2000

RLA2_1

0.2 OHMM 2000

RLA3_1

0.2 OHMM 2000

RLA4_1

0.2 OHMM 2000

RLA5_1

0.2 OHMM 2000

TENS_1

10000 LBF 3000

4

5

6

7

8

9

10

1112

131415

16

1718

19

20

2122

2324

2526

27

2829

30

31323334

35

36

37383940

4142

43444546

47

4849

5051

5253

54

5556

5758

5960

61

62

63

64

65

6667

68

6970

71

727374

75

7677

787980

8182

8384

8586

87

888990

91

92

939495

96

9798

99

100

101

102

103

104 105

106 107

108

109

110 111

112 113

114

115 116

117 118 119

120

121 122

123

124

125 126 127

128

129 130

131

132 133

134 135

136

137

138 139

140 141 142

143

144

145

146 147 148

149

150 151

152 153

154CORE_TRA.SAMPLE_ID

NPHI_1

0.3 V/V -0.1

NPHI_N_3

0.3 MV -0.1

RHOZ_1

2.18 G/C3 2.88

RHOBC_4

2.18 G/C3 2.88

CDEN_1

2.18 G/C3 2.88

crhob

2.18 FEET 2.88

PEFZ_1

10 B/E 0

2.55RESERVOIR_INT.RHOBC_AM

BVH_3

0.2 V/V 0

BVH_RHOB_TRS_3

0.2 V/V 0

PHIE_3

0.2 V/V 0

vol_toc

0 V/V 0.4

VOL_TOC_3

0 V/V 0.4

VP_TOC_1

0 V/V 0.4

VP_TOC_2

0 V/V 40

pign

0.2 V/V 0

CPHI_1

20 V/V 0

CPHI_GAS_1

20 V/V 0

0.060 RESERVOIR_INT.VOL_TOC_AM0.056RESERVOIR_INT.BVH_AV

VCLAY_3

0 V/V 1

vcl_grlim

0 V/V 1

VP_VCLAY_1

0 V/V 100

0.429RESERVOIR_INT.VCLAY_AM

SW_3

1 V/V 0

CSW_1

100 V/V 0

suwi 1 V/V 0

CSO_1

0 F/MN 100

0.127 RESERVOIR_INT.SW_AV

CPERM_1

1.e-06 V/V 1

CPERM_12_20_1

1.e-06 V/V 1

CPERM_COMPOSITE_1

1.e-06 V/V 1

cperm

1.e-06 V/V 1

CKPERM_3

1.e-06 B/E 1

PERM_DENONLY_1

1.e-06 MM2/MS 1

KH_PRO_1

1.e-06 B/E 1

kintx

1.e-06 MD 1

T_FLOW UNIT

T_ONONDAGA

T_HUNTERSVILLE

PERFS.COMPLETION PETRO.FORMATION

0.1012 RESERVOIR_INT.CKPERMH0.000484RESERVOIR_INT.CKPERM_AM

Lateral Placement

● Target highest quality rock with 

consideration given to stress profile 

and fracture geometries

● Preferred lateral placement in upper to 

middle portion of target zone to 

optimize proppant placement

● Toe high with option of traversing the 

entire section
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Mechanical Properties and Stress

Estimation from Acoustic Logs

Elastic Moduli Estimated from Acoustic 

Logs

Several Stress Equations are Appropriate

Uniaxial Transverse Isotropic Equation 

(Lateral Strain Model):

σHmin = (Eh/Ev)(νv/(1-νh))(σv-αPp) + 

αPp + (Eh/(1-vh

2

))εhmin + (Ehvh/(1-

vh

2

))εhmax

This equation expands the σtectonic to 

incorporate lateral strain. Tectonic strain 

creates greater stress in stiff 

sandstone/limestone beds and less 

stress in organic-rich shales.

Estimated Stress Calibrated with Well 

Test
13

Pump-In Testing: Key Calibration

Pump-In Tests

Conventional Pump-In Tests in Cased Hole

― Closure Stress is Determined

― After Closure Analysis

MDT Pump-In Tests in Open Hole

― Closure Stress is Determined

Core Data

The pump-in tests along with the core 

data calibrate mechanical properties 

data. 
14

Fracture Model – Mechanical Properties

Petrophysics processes the Dipole Sonic log for rock mechanical properties and 

that data is utilized in the frac model.
15

Fracture Model – Fluid Flow and Leakoff

The fluid loss data input into the model.
16

Fracture Model Methodology

The actual deviation survey for the well that is being modeled, as well 

as the planned perforations for the well, are entered.

A pump schedule is entered into the fracture model.

Numerous iterations with different pump schedules, perforation 

schemes, and other variable modifications are run to “optimize” the 

design.

What is the play specific “optimum” design?

Covers the height of the pay interval

Creates a sufficiently conductive propped fracture length that fits our well and 

perf spacing, with some overlap.

Minimizes well interference.

Provides the best production results based on reservoir flow simulation.
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Example Frac Model Results

As depicted in the model, the 

fracture propogates primarily only 

in the lower stress portion of the 

rock.

The lower stress portion of the 

reservoir “contains” the frac

High stress barriers exist above 

and below the fracture matching 

lithology changes.

Vertical variations in stress exist 

throughout the sections depicted.
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Example Frac Model Results

Fracture is contained by lower 

stress interval and high stress 

barriers above and below the 

lower stress interval.

Variable stress throughout 

section, matching lithology

changes

Greater height growth typically 

leads to less fracture length.

Note, this is predicted fluid 

distribution, not predicted 

propped fracture length.
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Perforation Clusters and Stage Spacing

250 ’– 500’ Stage Spacing

50 ’– 100’ Cluster Spacing

Not To Scale
20

Fluid Selection

Utilize core data and lab fluid-rock sensitivity testing to 

determine fluid additives

Maximize slickwater volumes vs. gelled fluid volumes

Utilize light gels/crosslink to place higher sand 

concentrations where necessary in gas shales

In liquids rich plays, more gels or crosslinked gels are 

utilized to promote greater conductivity in the propped 

fractures

Reservoir modeling suggests higher primary fracture 

conductivity required to improve well performance

CHK Promotes development and leads in the use of 

“greener”, more environmentally friendly hydraulic 

fracturing additives
21

Green Frac Status – Chemical Additives

Additive Barnett Fayetteville Haynesville Marcellus Eagle Ford

Friction Reducer GF* Test GF Test GF Test GF Test GF Test

Biocide GF Test GF Test GF Test GF Test GF Test

KCl Substitute Eliminated GF Substitute GF Substitute Eliminated GF Substitute

Scale Inhibitor GF Test GF Test X X

Surfactant Eliminated Eliminated Eliminated Eliminated X

Gel X X Occasional X

Cross-linker X X

Breaker X X Occasional X

HCl X X X X X

* - Green FracTM
22

Proppant Selection

100 mesh sand is typically used in the early portion of 

the job for enhanced distance and height, diversion, 

etching, and as a propping agent

40/70 and 40/80 mesh proppants are currently the 

predominant proppants used in gas shales

30/50 and 20/40 proppant used in some areas for 

fracture conductivity enhancement (especially important 

in the liquids rich plays)

Resin Coated Tail-Ins - used where sand flowback is an 

issue or where more proppant strength and conductivity 

are needed

Ceramic Proppants are utilized where higher conductivity 

and higher strength are required 

Increased proppant volumes and less fluid addresses 

conductivity and environmental issues
23

Execution
24

Hydraulically Fracturing the Shale

Typical Hydraulic Fracturing Job:

• 10-20 Pumps

• 2-4 Sand Storage Units

• Blender

• Hydration Unit

• Frac Tanks

• Chemical Storage Truck

• Data Monitoring Van

• 20-30 Workers
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Hydraulically Fracturing the Shale

6 layers of protection 

between the wellbore and 

groundwater aquifers 

during hydraulic fracturing 

operations.

Horizontal shale wells are 

hydraulically fractured at 

depths that typically 

exceed a mile beneath the 

groundwater.
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Summary

Planning and executing an “optimum” hydraulic 

fracture requires a multidisciplinary approach of 

gathering data, confirming data, modeling the 

optimum fracture and well performance, and 

executing a plan based on those models.

Hydraulic Fracture models do a good job of 

depicting and/or predicting vertical barriers and 

thus fracture growth.

This data has been, and continues to be, confirmed 

in multiple ways.

― Microseismic

― Lab Tests

― Core Data
27

Summary

Extensive data collection results in 

hydraulic fracturing jobs that are 

designed to remain in the proper 

formation

Remaining in the zone of interest 

maximizes production and minimizes 

opportunities to negatively impact 

production

Hydraulic fracturing is a highly 

engineered process that takes into 

account numerous variables.
28

Thank You – Questions?

Tim Beard

Sr. Engineering Advisor - Completions

Chesapeake Energy Corporation

6100 N. Western Avenue ı Oklahoma City, OK 76118 ı 405-935-8000

AskChesapeake@chk.com ı chk.com ı NYSE: CHK