OVERVIEW

Ahmed Abou‐Sayed

Advantek International

Sustainable Fracturing Rationale 

to

Reach Well Objectives –

The Impact of Uncertainties and comp

on

Compliance Assurances 
Variety of Fracturing Configurations Frac Pack High Perm Selective Stimulation Longitudinal Fractures Multiple Transvers

Fractures Selective/ 

Matrix Tre

Stimulation fo

Selective Injecti
MIGRATION, BREACHING & FAULT/SEAL INTEGRITY Deepest Protected Aquifer Fault Dipping at ~xo Distance ft Distance ft Top of Injection Layer Top of Upper Containment Layer Leak Rate ft3/min Invasion Rate ft3/min Lithology Markers
Fracture Shape & Proppant Concentration Diagram For Different Injection Scenarios and Complex Models 2500 3000 3500 4000 4500 5000 5500 4752 ft Injection Point Mid Sand Layers Modeled 5390 bbls Injected

0.81 psi/ft Shale Stress Gradient

3280 ft Injection PointMid Sand Layers Modeled14000 bbls Injected0.85 psi/ft Stress Gradient

4752 ft Injection PointMid Sand Layers Not Modeled13400 bbls Injected0.81 psi/ft Stress Gradient

1.

2. 3.

PropConcentration0.6135940.5726880.5317810.4908750.4499690.4090630.3681560.327250.2863440.2454380.2045310.1636250.1227190.08181250.0409063

0.6240.5930.5630.5320.5010.4710.4400.4090.3790.3480.3170.2870.2560.2250.195

PropConcentration0.6135940.5726880.5317810.4908750.4499690.4090630.3681560.327250.2863440.2454380.2045310.1636250.1227190.08181250.0409063

3280 ftCasing Shoe

4752 ftCasing Shoe

1. 2. 3.

Depth

(ft TVD)

4752 ft

4752 ft

3280 ft
STRESS ANISOTROPY EFFECT 40-60 0100 200 300 400 500 600 Increased Intercept Pressure (psi) 20-40 0-30 0-20 60-90 30-60 56 66 6 9 6 Well Deviation (degrees) Well Azimuth (degrees) Number of wells in category 

Fractur

σhmax 
Fractured Horizontal Wells

0

2,0004,0006,0008,000

10,00012,00014,00016,000

0 1,000 2,000 3,000 4,000 5,000 6,000 7,000 8,000 9,

Deviation from Vertical (ft)

Maersk MF-A15

Tate Unrein #4

TipTop #77X-17G, 14-8, 33-16

J. Snowden #7 Mordred 48/1

Soehlingen Z-10

Ameland 204

Parks #19-29, 14-20, 24-1, HC-23, TX

Witt 2-5

Tip Top 14-16

Rhodes #4

White 3,4

Parks 9-4
p g Shmax Shmin x - linked gel plug pressure operated vent 1st treatment 2nd treatment2000 -3000' Pump into annulus Pump into tbg Shmax Shmin Fr

2200' - 5000'
Horizontal Well Technology (Completions/Stimulation

Multiple - Simultaneous transverse fracturing: cased hole Shm

A - Zone Pre - conditioning Individual breakdown simultaneous extreme OB perforation stim propellant fracture ( frac 1 bigger than frac 2 )

1

1

B - Pumping with double rate in limited entry perforation
Gas Potential Effect of Number of Fractures on Cum Production 0 5 10 15 Time (days × 10^3) 0102030

Gas Cum. Production (MMscf × 10^3)

(1)

(3)

(2)

(1) 7 Fracs(2) 5 Fracs(3) 3 Fracs
Gas Potential Effect of Fracture Length on Cumulative Production 0 5 10 15 Time (days × 10^3) 0102030

Gas Cum. Production (MMscf × 10^3)(1)(2) (3)(4) (1) Lf = 500 ft (2) Lf = 300 ft (3) Lf = 150 ft (4) Lf = 100 ft
1000m 13- 3/8" @ 1000m MD 9- 5/8" @ 2950m MD 4- 1/2" Frac & Production Tubing 7" Liner @ 4576m MD Retrievable Bridge Plug 5" Cemented Liner with 5" HW Joints for setting Bridge Plugs (1484m) 5" HW Joints Cases 2B: 5" Complet

PBR Multi-Frac Horizontal Well
PRESSURE DURING SEQUENTIAL PUMPING 0 1000 2000 3000 4000 5000 6000 7000 8000

Time (min)

0

500

100015002000

Bottomhole Pressure (PSI)

Atoka Injections

BHP

80100120140160180

Temp (f)

Temp

Stress along Well due to 

Concurrent Parallel Fractures

Pressure Increase due 

to Series Fractures

Concurrent Fractures

Injected Fluid

Plugged T

New Fracture
• Strongly anisotropic, layered stress field MULTIPLE FRACTURING OF LONG HORIZONTAL WELLS – ANISOTROP
FRACTURE NETWORK IN A WEAKLY ANISOTROPIC STRES

After Olson, ARMA 2008

Conjugate Fractures
CONCLUDING REMARKS
• Hydraulic fracturing has been a reliable contributor to 

supply for half a century. They must be thoroughly des

• Fracture design requires site/well specific input, routin

solutions are not appropriate for assurance. • Well trajectories vis a vis stress field azimuth play a main establishing treatment pressures and well connectiv

• Breaching, loss of containment and frac fluid migration 

always be significant factors in job design and impleme

• Assurance must be a primary factor in stimulation via c

data collection, sophisticated modeling and live monito

• Pressure transient tests have advanced and are current

sufficient and necessary for better identification of frac

• Multiple fractures in single wells must be designed with sufficient certainty and complexities and need close mo

CONCLUDING REMARKS

Half Fracture Length (ft)

Fracture Height (ft)

0 500 1000

-400-300-200-100

0

100200300400500

1.1061.0330.9590.8860.8130.7400.6670.5940.5200.4470.3740.3010.2280.1550.081

Fracture Shape and Width (inches)

(V = 14000 bbls at 4 bpm w/o Solids)

High Leakoff

0 1000 2000 3000

Half Fracture Length (ft)

-500

0

500

1000150020002500

Fracture Height (ft)

0.5500.5040.4570.4110.3650.3180.2720.2250.1790.1330.0860.040

Solids Concentration By Volume

Solid particles were simulated as2 ppg proppant. Solid pluggingand dehydration are indicatedwhen the fracture enters into thepermeable sand (at the top).

0 500 1000 1500 2000 2500

Half Fracture Length (ft)

-1000

-500

0

500

1000

Fracture Height (ft)

0.8230.7680.7140.6590.6050.5510.4960.4420.3880.3330.2790.2250.1700.1160.061

Modulus Barrier

Width (in)

Layer with High Elastic Modulus

High Stiffn

Stress Barrier 

Strength Half Fracture Length (f

Fracture Height (ft)

0 100 200 300 400 500 

-200-100

0

100200300

Solid Concentration by Vomu

SchematStress Pr

Complex Medelling