Transcript What We Can Learn from Granite Wash Fracture Stimulation

What Can We Learn from Granite Wash
Fracture Stimulation Pressure Response?
WHEELER & HEMPHILL COUNTIES, TX
March 6, 2008 – Norman, Oklahoma
Bob Shelley
RED TECHNOLOGY ALLIANCE, LLC
Bill Grieser
HALLIBURTON ENERGY SERVICES, INC.
Fracture Stimulation Pressure Response
 A normal fracture pressure tend either increases slightly or
remains relatively flat throughout a hydraulic fracturing
treatment.
 A decreases in fracturing pressure can be interpreted as excessive
fracture height growth or out of zone propagation.
 Moderate increases in net fracturing pressure can be attributed to
fracture confinement, tip effects and/or proppant friction.
 Large increases in net fracturing pressure can be explained by the
occurrence of multiple fractures and/or proppant bridging.
 We have observed a wide variation of stimulation pressure
response (increases) on granite wash treatments. The magnitude
of some indicate the presence of multiple fractures.
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OGS Granite Wash Conference March 6, 2008
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Multiple Fractures
Formation-induced
multiple fractures
Completion-induced
multiple fractures
Long
perforated
interval
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Short
perforated
interval
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The Effect of Increasing the Number of Propagating Fractures
3
Net Fracturing Pressure
Fracture Radius
Fracture Width
Dimensionless Ratio
2.5
2
1.5
1
0.5
0
1
2
3
4
5
Number of Fractures
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Frac Treatment Pressure Evaluation Methodology
10000
50.0
Pressure
Rate
9000
40.0
Injection/Shut-In Test
Volume - 9,180 g
Maximum Rate - 40.5 BPM
Pump time - 9 min
Perforations - 12,448 to 12,462, 4 SPF
12495 to 12503, 4 SPF
12521 to 12547, 4 SPF
Pump-In Leakoff Factor - 1.4 min
7000
6000
35.0
30.0
5000
25.0
Frac Treatment
Volume - 77,500 g
Prop - 53,200 lb 20/40 Ultraprop
5,100 lb 100 M
Average Prop Conc - .54 lb/g
Maximum Prop Conc - 2.7 lb/g
Average Rate - 34.5 BPM
Pump Time - 55 min
BHTP Increase > 3,000 psi
4000
3000
20.0
15.0
2000
10.0
1000
5.0
0
14:57:00
Rate (BPM) and Prop Concentration (lb/g)
8000
Pressure psi
45.0
Prop Conc BH
0.0
15:07:00
15:17:00
15:27:00
15:37:00
15:47:00
15:57:00
16:07:00
16:17:00
16:27:00
16:37:00
Time
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OGS Granite Wash Conference March 6, 2008
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Pump-In Leakoff Factor (PILF) Measurement
Injection/Shut-In Test
7000
60.0
Pressure
Rate
6500
50.0
Pump-In Leakoff Factor Definition
Time in minutes for a 200 psi pressure drop
starting 1 minute after shutdown initiation.
In this case 1.4 min.
40.0
5500
30.0
1.0
1.4
5000
4500
4000
15:10:30
Rate BPM
Pressure psi
6000
20.0
10.0
200
0.0
15:11:30
15:12:30
15:13:30
15:14:30
15:15:30
Time
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OGS Granite Wash Conference March 6, 2008
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Granite Wash Treatment Summary
WELL
1
2
3
4
5
6
7
8
9
10
11
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TOP
11563
11495
11547
11569
12340
12327
12544
12534
12348
12440
12546
BOTTOM
11453
11388
11170
11261
12284
12290
12448
12412
12274
12348
12405
GROSS PERF
110
107
220
210
56
37
96
122
74
92
141
RATE BPM
40
40
60
60
30
30
50
50
40
50
40
OGS Granite Wash Conference March 6, 2008
PILF
20
22
21
19
4
5
9
10
14
16
15
FRAC TREATMENT PRESSURE RESPONSE
Normal - Frac went to completion
Normal - Frac went to completion
Normal - Frac went to completion
Normal - Frac went to completion
Screen Out on 2 ppg; 68 min
1/1 slope with 1/3rd 4ppg in; 70 min
Normal - Frac went to completion
1/1 slope with 1/2 6ppg in; 118 min.
Normal - Frac went to completion
Normal - Frac went to completion
1/1 slope with 1/4 8 ppg in; 155 min.
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Injection/Shut-In Test PILF vs. Frac Pressure Response
40
Granite Wash; TX Panhandle
Mississippian Data; Williston Basin
35
Frac Treatment Pressure Increase (psi/min)
Mississippian Best Fit
30
25
20
15
10
5
0
1
10
100
Injection Test Pump-In Leakoff Factor (min)
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OGS Granite Wash Conference March 6, 2008
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Production vs. Injection/Shut-In Test PILF
25
Injection Test PILF
20
15
10
5
0
0
200,000
400,000
600,000
800,000
1,000,000
1,200,000
First 12 Month Gas MCF
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Summary
 The Injection/Shut-In Test PILF measurement can be used as an
indicator of reservoir productivity (Extent of Natural Fracturing).
 Natural Fractures are needed to obtain Granite Wash Reservoir
Connectivity.
 Natural fractures in the Granite Wash contribute to the occurrence
of multiple fractures which are detrimental to the placement of
large hydraulic fracture stimulation treatments.
 The PILF measurement obtained from an injection/shut-in test
can be used to predict hydraulic fracture stimulation pressure
response for Granite Wash Frac Treatments.
 The stimulation pressure response observed on granite wash
treatments is consistent with the pressure response for other
naturally fractured reservoirs such as the Mississippian Carbonates
in the Williston Basin.
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OGS Granite Wash Conference March 6, 2008
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