Well Planning and Construction

Haynesville Shale – East Texas

Carolyn S. Debrick, PE

Drilling Engineering Manager – Southern Division
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Agenda

• Haynesville Shale

• Well Planning – Design

• Well Interference

• Surface Casing Setting Depth

• Casing Design Considerations

• Surface Casing Cement Design 

• Production Casing Cement Design
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Haynesville Shale

East Texas

• Located in East Texas, Six Counties

• Total Vertical Depth: 10,500’ to 13,600’

• Measured Depth: 15,500’ to 20,000’

• Pore Pressure: 15 ppg to 18 ppg

• Shale Frac Gradient: > 1.0 psi/ft

• Treatment Pressure > 10,000 psi

• Bottom Hole Temperature: 270 to 350 F
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Well Planning - Design

Pore Pressure, Frac Gradient, & Casing Seat Selections

Leak Off Test data

Disposal Zones

Depleted Zone
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Well Planning – Designs (cont.)

Duck Creek

Anhydrite

Rodessa

Pettit

Travis Peak

Cotton Valley

Bossier

Haynesville

2200

5000

5400

5900

6300

8000

9900 

-12500

10500 

-13600

9 - 14

9

9 – 13.8

2 - 9

4 to 9.8

4 to 9.8

14 - 17

14- 17

2000’

Knowles 

Lime and 

11.5 to 

12.5 ppg 

MW

1000’

1500’

Stage 

Cement 

Tool

Panola County

10,300’ TVD

Harrison County 

10,800’

Exploration, South

Geologic Cross Section 13,600’ TVD, 350 F

Formation Depth, ft MW, ppg
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Well Interference: Anti-Collision 

• Directional planning off a pad

• Different survey tools

• Separation Factor
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Surface Casing Setting Depth & MASP

• Base of Wilcox, Panola County: 250 ft to 350 ft

• Requirement is 200 ft or less below the base

• Maximum Anticipated Surface Pressure – MASP

• Devon sets surface casing at depth greater than prescribed by regulator to 

protect the USDW, the rig, and personnel

• MASP = Fracture Gradient – maximum Mud Weight planned for next hole section

Surface 

Casing Depth

Fracture 

EMW

Planned Mud 

Weight

MASP

600 ft 11.5 ppg 10 ppg 47 psi

1,000 ft 12.5 ppg 10 ppg 130 psi

1,500 ft 13.5 ppg 10 ppg 234 psi
NYSE: DVN www.devonenergy.com page 8

Casing Design Considerations

• Loads

– Drilling

– Casing running loads

– Stimulation

– Production

• Connection Selection

– Pressure application, API or premium

– Bending strength

– Need to rotate

– Compression and tension efficiency

– Surface casing connection – Wellhead load structural 

requirements
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Surface Casing Cement

• Class A Cement

– 15 ppg tail, 30% annular height

– Extenders & accelerators added to lead

– Cement returns to surface

• Haynesville Field Practices

– Condition mud 

– Keep ECD below fracture strength

– Pump spacers

– Run centralizers

– Reciprocate casing

– Test casing shoe after drilling out

• Cement Design on Next String

– Top of cement (TOC) into shoe of 

surface casing

– Or, Run cement bond log (CBL) to 

determine if TOC is sufficiently above 

any zone to be stimulated
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Production Casing & Cement

Haynesville Horizontal Well

• Design concerns

– Close tolerance between hole & casing size

– High mud & cement weights; therefore more 

circulating friction

• Haynesville Field Practices

– Run surge & swab to determine casing running 

speed 

– Reduce mud yield point before tripping to run 

casing

– Design low rheology cement

– Run cement job ECD’s to determine cement 

displacement rates & ensure below fracture

– Run swell packer if job ECD & fracture 

strength close

• If flow after cementing is a concern:

– Shut in annular

– Hold pressure & wait until cement sets

– Run a CBL before perforating
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Production Casing & Cement (cont.)

Haynesville Horizontal Well

Design Considerations:

• Zero free water

• Fluid loss below 150 cc

• Adequate turbulent 

spacer

• Expander

• Gas Stop

Example Tests:

• Lab tests are performed 

on new slurry design to 

ensure they perform as 

designed – Example test.
Thank You.