wtn mtm #8 aguichard
TRANSCRIPT
On Deepwater Perforating,
Deconvolution, and Cleanup Modeling
Aurelien Guichard
Well Testing Network – Multi Topic Meeting MTM #8
Houston, Texas – May 1st, 2009
WTN – Multi Topic Meeting #8 – Houston, Texas
Agenda
Topic #1: Deepwater perforating
– Characteristics, challenges, and proposed solutions
– Wellbore pressure and downhole forces modeling
– Perforating results and sensitivity analysis
Topic #2: Deconvolution
– How to benefit from deconvolution
– Results from synthetic and actual datasets
Topic #3: Cleanup modeling
– Case study in the Gulf of Mexico
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #1: Deepwater Perforating
Characteristics of deepwater perforating
• Water depth up to 7,000 ft
• Well depth up to 30,000 ft
• Reservoir pressure up to 25,000 psi
• Unconsolidated rocks; low perm; sand control
• Large bore casing program up to 10 1/8 in
• Completion fluid weight up to 15 ppg
• Perforation interval up to 300 ft
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #1: Deepwater Perforating
Challenges: And solutions:
• Potential gun sanding
– None or limited flowback: 10-20 bbl
– Upon perforating, pull up the gun string before flowing
– Gun drop: controlled-tension release & automatic release systems
• Gun shock
– Stronger TCP packer
– Upgraded shock absorbers
– Optimal toolstring design
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #1: Deepwater Perforating
Wellbore pressure and downhole forces modeling
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #1: Deepwater Perforating
Successful
perforations
& frac/pack
in GoM Wellbore Pressure
shows
Dynamic Underbalance
upon Perforating
(Actual Data)
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #2: Deconvolution
Advantages of deconvolution over conventional well test analysis
• Includes entire production history
• Extends radius of investigation
• Confirms reservoir behavior and boundaries where short, individual pressure buildups cannot
• Enhances reserve estimates
To benefit from deconvolution algorithms, importance of
• Well test objective and subsequent design
• Equipment selection, specifically surface rate measurements
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #2: Deconvolution
Synthetic dataset
Production #1: 75 d
Buildup #1: 4.2 d
Production #2: 44 d
Buildup #2: 6.3 d
Total: 130 d
4200
4600
5000
Tes
t Des
ign
[psi
a]
0
200
400
Pro
du
ctio
n [S
TB
/D]
production #1 build-up #1 production #2 build-up #2
Gro
up
s
0 1000 2000 3000
Pressure [psia], Liquid Rate [STB/D], Not a unit vs Time [hr]
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #2: Deconvolution on Synthetic Dataset Conventional model
identification and
history match (red)
One fault
Log-Log plot: dp and dp' [psi] vs dt [hr]Log-Log plot: dp and dp' [psi] vs dt [hr]
Log-Log deconvolution plot: dp and dp' [psi] vs dt [hr]
Bourdet derivative
Deconvolution (blue)
Two faults
History plot (Pressure [psia], Liquid Rate [STB/D] vs Time [hr])
Conventional Analysis: Poor Match
History plot (Pressure [psia], Liquid Rate [STB/D] vs Time [hr])
Analysis with Deconvolution: Perfect Match
130 days 1 hr 100 hrs
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #2: Deconvolution on Actual Dataset
Cleanup
13 days 14000
16000
18000
BH
P3
[p
sia
]
0
2000
4000
6000
Pro
du
cti
on
[S
TB
/D]
build-up #3 production #4 build-up #4 (155.567 hr) production #5 build-up #5 (110 hr)
Gro
up
s
5/10/2006 5/16/2006 5/22/2006 5/28/2006 6/3/2006
Pressure [psia], Liquid Rate [STB/D], Not a unit vs Time [ToD]
Initial
Buildup
6.5 days
Main
Flow
10 days
Final
Buildup
4.5 days
Multiphase
Rates
at Surface
from Vx*
Downhole
Quartz
Pressure
from HPQG
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #2: Deconvolution on Actual Dataset
Log-Log plot: dp and dp' [psi] vs dt [hr]
History plot (Pressure [psia], Liquid Rate [STB/D] vs Time [hr])History plot (Pressure [psia], Liquid Rate [STB/D] vs Time [hr])
Log-Log plot: dp and dp' [psi] vs dt [hr]
A C
Log-Log plot: dp and dp' [psi] vs dt [hr]
History plot (Pressure [psia], Liquid Rate [STB/D] vs Time [hr])
B
Model B
19,241
1,660
415
2,320
Model A
19,500
1,310
513
913
Model C
19,362
1,270
372
1,070
IARF
Pi (psi)
kh (md.ft)
Xf (ft)
Fc (md.ft)
1 hr 100 hrs
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #2: Deconvolution on Actual Dataset
History plot (Pressure [psia], Liquid Rate [STB/D] vs Time [hr])History plot (Pressure [psia], Liquid Rate [STB/D] vs Time [hr])
Log-Log deconvolution plot: dp and dp' [psi] vs dt [hr]
IARF
19,362
1,270
372
1,070
Model
Pi (psi)
kh (md.ft)
Xf (ft)
Fc (md.ft)
Decon
19,246
2,060
181
553
Log-Log plot: dp and dp' [psi] vs dt [hr]
IARF
Deconvolution sees two boundaries
and improves history match!
31
days 1 hr 100 hrs
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #3: Cleanup Modeling
Cleanup Planner, a proprietary tool for the
planning phase of well cleanups:
• Built inside the Petrel RE environment
• Runs Eclipse simulations
• Accounts for drilling/completion fluids lost to
the formation
• Determines optimal flow profile and
drawdown
• Designs cleanup program, choke sequence,
expected duration of cleanup, flowback
volumes, BS&W trends, drawdown behavior,
and resulting well productivity
WTN – Multi Topic Meeting #8 – Houston, Texas
Topic #3: Cleanup Modeling
Case study in GoM: model and actual water cut during cleanup