000401_SPE_ATW_Calgary_Arun_Wel_Prf_Stdy
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Transcript 000401_SPE_ATW_Calgary_Arun_Wel_Prf_Stdy
Well Performance Analysis in a Multiwell
Gas Condensate Reservoir—
Arun Field, Indonesia
Presented at
SPE Advanced Technology Workshop
Well Testing in Gas Condensate Reservoirs
1-2 April 2000, Calgary, Alberta, Canada
T. Marhaendrajana, Texas A&M University
N.J. Kaczorowski, Mobil E&P (U.S.)
T.A. Blasingame, Texas A&M University
Summary—Well Test Analysis
A representative summary of the analysis
and interpretation of well test data taken
from the Arun Gas Field (Sumatra, Indonesia) (Single-phase gas analysis is used).
2-zone radial composite reservoir model is
effective for diagnosing the effects of condensate banking at Arun Field.
Application of a new solution for the
analysis and interpretation of well test data
that exhibit "well interference" effects.
Summary—Production Data Analysis
Analysis and interpretation of production
data using (single-phase) decline type
curve analysis:
Permeability-thickness product
Skin factor
Original and movable gas-in-place
Comparison of results from well test and
production data analyses vary—but these
variations appear to be consistent.
General Information—Arun Field (Indonesia)
Field Description
Arun Field
Located
Ø
in Northern part of
Sumatra, Indonesia
Retrograde gas reservoir
One of the largest gas fields
in the world
Arun Field has 111 wells:
Ø
Ø
Ø
Ø
Ø
79 producers
11 injectors
4 observation wells
17 wells have been abandoned
Ø
Ø
N
Ø
Ø
Ø
Ø
Major Phenomena Observed at Arun Field
Liquid accumulation near wellbore (condensate banking)
Need to know the radial extent of the condensate
bank for the purpose of well stimulation.
Well interference effects (well test analysis)
Well interference effects tend to obscure the
"standard" flow regimes—in particular, the radial
flow response.
This behavior influences our analysis and interpretation efforts, and we must develop an alternative analysis approach for well test data
affected by multiwell interference effects.
Well Test Analysis Strategy
Condensate banking phenomenon:
Used a 2-zone radial composite reservoir
model—the inner zone represents the "condensate bank," and the outer zone represents
the "dry gas reservoir." (reported kh-values
are for the "outer zone")
Well interference effects:
Developed a new method for the analysis of
well test data from a well in multiwell reservoir
where we treat the "well interference" effect as
a "Regional Pressure Decline." (This phenomena is observed in approximately 35 cases)
Well Test Analysis: Examples
Well C-I-18 (A-096)—Test Date: 28 Sep. 1992
Radial composite effects.
Multiwell interference effects.
Well C-IV-01 (A-060) [Test Date: 25 Feb. 1993]
Radial composite effects.
Multiwell interference effects.
WT Example 1: Log-log Summary Plot
Well C-I-18 (A-096) [Test Date: 28 September 1992]
3
Pseudopressure Functions, psi
Functions, psi
Pseudopressure
10
Raw data
Corrected
2
10
Improvement of
Infinite-acting Reservoir Model
pressure derivative.
(Does not include non-Darcy flow)
1
10
Condensate banking
region.
Higher mobility
region.
Closed boundary at 160 ft?
(includes non-Darcy flow).
0
10
-1
10
-4
10
-3
10
-2
10
-1
10
0
10
Effective Shut-in Pseudotime, tae, hrs
Effective
shut-in pseudotime, hrs
1
10
WT Example 1: Horner (Semilog) Plot
Pseudopressure,
Shut-in
Shut-in
Pseudopressure, ppws , psiapsia
WellWell
C-I-18
(A-096)
Date:2828September
September
1992]
C-I-18
(A-096)[Test
[Test Date:
1992]
1160
1140
Condensate banking
region.
1120
Higher mobility
region.
1100
1080
1060
Raw data
Corrected
1040
1020
3
10
2
10
1
10
Horner Pseudotime, ( ta+tpa)/ta (tpa=tp=1.56 hr), hr
Horner
pseudotime, hrs (tp = 1.56 hr)
0
10
WT Example 1: Muskat Plot (single well pavg plot)
pseudopressure,
Shut-in
Shut-in
Pseudopressure, ppws , psiapsia
C-I-18
(A-096)[Test
[Test Date:
Date: 28
1992]
WellWell
C-I-18
(A-096)
28September
September
1992]
1150
pp,avg = 1148.6 psia
Data deviate from the "Muskat line"
—indicating interference effects
from
surrounding
wells.
Onset
of boundary
dominated flow
(single well analogy).
"Transient flow"
1149
1148
1147
1146
1145
1144
1143
1142
0
2
4
6
dp pws
dppws
/d/dtta,,psi/hr
psi/hr
a
8
10
WT Ex. 1: "Well Interference" Plot (radial flow only)
Well
C-I-18
(A-096)
Date:2828
September
1992]
Well
C-I-18
(A-096) [Test
[Test Date:
September
1992]
15
Intercept is used to
calculate permeability.
ae
(p(pp')p')ttae,,psipsi
10
5
Slope is used in the
pressure correction.
0
-5
(pp')tae <0, indicating multiwell
interference effects.
-10
-15
0
5
10
15
2
ttaa/2/tae, hrs
tae
20
25
30
WT Example 2: Log-log Summary Plot
C-IV-01
(A-060)[Test
[TestDate:
Date: 25
1993]
WellWell
C-IV-01
(A-060)
25February
February
1993]
3
psi
Functions,
Pseudopressure
Pseudopressure Functions,
psi
10
Raw data
Corrected
2
10
Improvement of
pressure derivative.
1
10
Condensate banking
region.
Reservoir
Model
ClosedInfinite-acting
boundary
at
330 ft?
Higher
mobility
(Does not
include non-Darcy
flow)
(includes
non-Darcy
flow).
region.
0
10
-1
10
-4
10
-3
10
-2
10
-1
10
0
10
Effective Shut-in Pseudotime, tae, hrs
Effective
shut-in pseudotime, hrs
1
10
WT Example 2: Horner (Semilog) Plot
Shut-in Pseudopressure,
Pseudopressure, ppws , psia psia
Shut-in
C-IV-01
(A-060)[Test
[TestDate:
Date: 25
1993]
WellWell
C-IV-01
(A-060)
25February
February
1993]
1650
1600
Condensate banking
region.
1550
1500
Higher mobility
region.
1450
1400
Raw data
Corrected
1350
1300
3
10
2
10
1
10
Horner Pseudotime, ( ta+tpa)/ta (tpa=tp=2.61 hr), hr
Horner
pseudotime, hrs (tp = 2.61 hr)
0
10
WT Example 2: Muskat Plot (single well pavg plot)
Shut-in
Shut-in pseudopressure,
Pseudopressure, ppws , psia psia
WellWell
C-IV-01
(A-060)
25February
February
1993]
C-IV-01
(A-060)[Test
[TestDate:
Date: 25
1993]
1575
pp,bar = 1573.5 psia
1574
Onset of boundary
dominated flow.
1573
1572
"Transient flow"
1571
1570
1569
1568
0
2
4
6
dp pws
dppws
/d/dtta, psi/hr
, psi/hr
a
8
10
WT Ex. 2: "Well Interference" Plot (radial flow only)
Well
C-IV-01(A-060)
(A-060) [Test
2525
February
1993]
Well
C-IV-01
[TestDate:
Date:
February
1993]
4
Intercept is used to
calculate permeability.
2
(pp')tae <0, indicating multiwell
interference effects.
ae
(pp(')ptp')aet , psi
3
1
0
Slope is used in the
pressure correction.
-1
-2
0
2
4
6
2
ta / tae
ta /2
tae, hrs
8
10
12
Correlation of Well Test Results—Arun Field
Maps:
kh (outer-zone (gas) permeability).
skin factor.
non-Darcy flow coefficient.
Radius of condensate bank.
Correlation of non-Darcy flow coefficient and the
permeability-thickness product (kh).
Flow Capacity (kh, md-ft)
from Well Test Analysis (Arun Field, Indonesia)
kh Map
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
16000
16000
kh
15000
15000
10000
5000
4000
20000
10000
30000
10000
9000
40000
8000
7000
30000
A-108
6000
A-017
A-107
10000
A-097
A-070A-048
A-060
A-041
A-084
A-062
50000
50000
7000
10000
20000
A-095
11000
A-078
A-015 A-080
A-034
A-016
A-035
A-077
20000
A-099
10000
8000
A-098 40000
A-058
A-071
20000
9000
12000
A-032ST
A-032
A-061 A-021
A-024
A-106
A-082
A-105ST2A-102 A-068
A-022ST2
A-029
20000
40000
A-083
A-033
A-089 A-073
A-040
30000
A-093
10000
10000
13000
A-027
10000
A-092
A-067
20000
A-088
20000
12000
11000
14000
A-081
A-036
A-076
A-045 A-079ST
30000
A-059
A-074
A-025ST
40000
A-042
A-054
A-096
20000
A-104
30000
13000
A-101
10000
14000
30000
A-103
x-position (relative distance)
distribution appears reasonable.
3 major "bubbles"
of kh noted, probably erroneous.
kh shown is for the
"outer" zone (when
the radial composite model is used).
1x2 Perspective
View
A-085
10000
A-049
6000
A-110ST A-046 40000 40000
A-100
A-053
10000
60000
A-091
80000
Legend: (Well Test Analysis)
A-051
50000
5000
Flow Capacity (kh) Contour Plot
(10,000 md-ft Contours)
Arun Field (Indonesia)
A-109
100000
4000
3000
3000
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
y-position (relative distance)
Skin Factor (Inner Zone)
from Well Test Analysis (Arun Field, Indonesia)
Skin Factor Map
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
16000
16000
Skin
15000
1x2 Perspective
View
15000
A-103
14000
14000
0
A-101
A-081
A-036
A-076
A-045 A-079ST
A-059
A-074
A-025ST
A-042
A-054A-104
A-096
5
1
1
3
A-067
12000
A-032ST
A-032
A-061 A-021
3
A-024
A-106
A-082
A-105ST2A-102 A-068
10
3
A-022ST2
A-029
1
A-083
4
A-033
A-089 A-073
A-040
A-093
4
10
A-110ST
-1
5000
4000
Legend: (Well Test Analysis)
Skin Factor Contour Plot
(Various Contours)
Arun Field (Indonesia)
A-046
15
7000
A-085
15
A-049
A-053 3
A-091
-2
1
0 A-051
-1
2
0 4
-1
A-017
A-097
A-070A-048
2
A-060
A-041
5
3
A-084 20
3
A-062
1
15
A-108
6000
15
8000
10
A-107
A-015 A-080
A-034
A-016
A-035
A-100
2
6000
5000
-1
7000
10000
0
A-077
A-095
2
0
10
A-099
11000
A-078
9000
A-098
A-058
A-071
0 2
3
8000
0
4
4
5 5
9000
2 2
2
4
10000
5
11000
-1
A-027
3 1 2
A-088
0
A-092
13000
3
12000
5
13000
5 4 2
1
x-position (relative distance)
factor distribution appears very
consistent.
Areas of "high skin"
indicate need for
individual well
stimulations.
Skin factors are
calculated based on
the "inner" zone of
the radial composite model (when rcmodel is used).
These results represent
the current completion
(evaluated using well test data).
A-109
4000
3000
3000
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
y-position (relative distance)
Logarithm of the Non-Darcy Flow CoefficientD,
( 1/MSCFD)
from Well Test Analysis (Arun Field, Indonesia)
D (Non-Darcy) Map
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
16000
16000
1x2 Perspective
View
15000
15000
A-103
A-081
A-036
-4
A-076
A-045 A-079ST
-3.8
A-059 -3.8
A-074
A-025ST
-5 A-042
A-054A-104
A-096
-4.8
-4.6
A-088 -4.2
A-067
-4.6 A-077
A-095
-4.8
7000
A-107
A-108
5000
4000
-4
A-017
A-097
A-070A-048
A-060
A-041
-4
A-084
A-062
-3.8
6000
A-015 A-080
A-034
A-016
A-035
8000
7000
-3.8
-3.6
-3.6
-3.4
-5
9000
-3.8
-4.8
A-099
-4.2
A-071
8000
10000
-4.2
A-098
-4.6
A-058
11000
A-078
-4
9000
12000
A-032ST
A-032
A-061 A-021
A-024
A-106
A-082
A-105ST2A-102 A-068
A-022ST2
A-029
-4.6
A-083
A-033
A-089 A-073
A-040
A-093
-4.4
10000
A-027
-4.6
A-092
13000
-4.2
12000
11000
14000
A-101
-4.2 -4
13000
No Data
-4.4
14000
x-position (relative distance)
map indicates a
uniform distribution.
"high" and "low"
regions appear to be
focused near a single
well.
Relatively small data
set (30 points).
-4.4
This
A-085
A-049
A-110ST A-046
A-053
Legend: (Well Test Analysis)
A-091
Logarithm of the Non-Darcy
A-051
Flow Coefficient
(log(10) Contours)
Arun Field (Indonesia)
A-109
A-100
6000
5000
4000
3000
3000
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
y-position (relative distance)
Condensate Bank Radius (ft) from Well Test Analysis
(Arun Field, Indonesia)
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
16000
16000
Condensate Radius Map
Good
15000
14000
13000
15000
A-103
No Data
14000
A-101
A-081
A-036
A-076
A-045 A-079ST
A-059
A-074
A-025ST
30
A-042
A-054A-104 25
A-096
13000
25
10
15
10
5
25
7000
10
20A-017
10
A-097
A-070A-048
A-060
A-041
A-084
A-062
10
7
A-108
20
25
A-107
8000
Condensate Bank Contour Plot
(Various Contours)
Arun Field (Indonesia)
20
4000
A-049
1 3
5000
A-085
3
7
5
A-110ST A-046
A-053
A-091
Legend: (Well Test Analysis)
25
A-051
7000
7
A-077
A-015 A-080
A-034
A-016
A-035
15
5
A-099
10
20
9000
A-095
6000
10000
25
8000
11000
A-078
7
5
A-098
35
A-058
A-071
3
9000
12000
15
A-032ST
A-032
A-061 A-021
A-024
A-106
A-082
A-105ST2A-102 A-068
A-022ST2
A-029
A-083
A-033
A-089 A-073
A-04030
A-093
5
10000
A-027
35
25 30
15 20
11000
25
A-092
A-067
40
12000
A-088
30
x-position (relative distance)
distribution of
values—"high" spots
probably indicate
need for individual
well stimulations.
Relatively small data
set (32 points).
1x2 Perspective
View
A-109
A-100
6000
5000
4000
3000
3000
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
y-position (relative distance)
D (Non-Darcy)—kh Crossplot
crossplot indicates an "order of
magnitude" correlation.
Verifies that nonDarcy flow effects are
systematic.
Non-Darcy Flow Coefficient ( D, 1/MSCFD)
from Well Test Analysis ( D at Time of Well Test)
D-kh
Comparison of Non-Darcy Flow Coefficient ( D) from Well Test
Analysis versus Flow Capacity ( kh) from Well Test Analysis
(Arun Field -- Indonesia)
3
4
5
6
10
10
10
10
-3
6
10
10
Slope = 2
-4
5
10
10
-5
4
10
10
Legend: DWT vs. khWT
Comparison of D from Well Test Analysis
versus kh from Well Test Analysis
(Arun Field -- Indonesia)
-6
3
10
10
3
10
4
5
10
10
Flow Capacity (kh, md-ft)
from Well Test Analysis ( kh at Time of Well Test)
6
10
Production Data Analysis: Arun Field
Well C-I-18 (A-096)
Limited history (no EURMB analysis possible).
Erratic performance.
Reasonable match on decline type curve.
Well C-IV-01 (A-060)
Good history (well was down for almost two
years in 1993-1995).
Sparse p/z data for EURMB analysis.
Early data match on decline type curve is
questionable.
Late performance data deviate from material
balance trend on decline type curve, indicating "well interference" effects.
WPA Example 1: Well History Plot
1.E+05
4000
TWS Gas
Arun Well A-96
Condensate
Water
FW HP
3000
SIBHP
1.E+03
2000
1.E+02
1000
1.E+01
1998
1997
1996
1995
1994
1993
0
1992
1.E+00
FWHP and SIBHP, psia
1.E+04
1991
q g,TWS and q g,Sep [MMscf/D], q c and q w [STB/D]
Sep Gas
WPA Example 1: Decline Type Curve Plot
Fetkovich-McCray Decline Type Curve
(No Well Interference Effects)
WPA Example 2: Well History Plot
1.E+05
6000
TWS Gas
Sep Gas
Condensate
1.E+04
Water
SIBHP
4000
1.E+03
1.E+02
2000
1.E+01
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
1988
0
1987
1.E+00
FWHP and SIBHP, psia
FW HP
1986
q g,TWS and q g,Sep [MMscf/D], q c and q w [STB/D]
Arun Well A-60
WPA Example 2: EURMB Plot
WPA Example 2: Decline Type Curve Plot
Fetkovich-McCray Decline Type Curve
(No Well Interference Effects)
WPA Example 2: Decline Type Curve Plot
Fetkovich-McCray Decline Type Curve
(Includes Well Interference Effects)
Correlation of Production Analysis Results—Arun Field
Production data analyzed using decline type curve
analysis—single-phase (gas) pp and ta used.
Flow Properties:
Maps:
Volumetric Properties:
Plots:
kh
skin factor
Crossplots:
khWT—khWPA
sWT—sWPA
G vs. time
EURMB vs. time
kh vs. time
Crossplots:
G—EURMB
EURPI—EURMB
Flow Capacity (kh, md-ft)
from Production Data Analysis (Arun Field, Indonesia)
kh Map
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
16000
16000
kh
15000
15000
A-103
13000
2000
A-099
A-077
4000
A-030
A-015 A-080
A-034
A-016
A-035
1500
2500
A-107
Flow Capacity (kh) Contour Plot
(500 md-ft Contours)
Arun Field (Indonesia)
1500
A-017 2000
A-097
A-070A-048
2000
A-060
A-041
A-085
A-108
A-084
2500
A-062
A-049
2500A-057
A-094
A-046
3000
A-110ST
A-047
A-100
A-053
2500
A-091
A-050
2000
1500
Legend: (Production Analysis)
A-0512000 3000
3000
2000
5000
10000
9000
A-098
A-058
A-071
A-095
6000
11000
A-078
3000
1000
A-111
7000
12000
1000
8000
A-088
2000
9000
2000
A-043
A-067
A-027
A-037
A-092
2500 A-032
A-061 A-021
A-024
A-106
4000
A-082
A-105ST2A-102 A-068
A-022ST2
4500
A-029
3000A-083 A-033
A-087
A-089 A-073
A-040
A-093
A-075
13000
A-025ST
A-042
2000
10000
1000
A-054A-104
1000
11000
A-059
A-074
1500
12000
14000
3500
A-081
A-036 2000
2500
1500 A-076
A-045 A-079ST
1000 1500
A-101
A-090
A-044
3500
14000
x-position (relative distance)
shown is computed using decline
type curve analysis
on early production
(pp and ta used).
kh distribution appears reasonable
(albeit lower than
WT estimates).
A few "bubbles" of
kh noted, these are
probably erroneous.
1x2 Perspective
View
2500
A-109
8000
7000
6000
5000
4000
3000
3000
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
y-position (relative distance)
Skin Factor (Inner Zone)
from Production Analysis (Arun Field, Indonesia)
Skin Factor Map
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
16000
16000
Skin
15000
1x2 Perspective
View
15000
A-103
14000
-4
A-081
A-036
A-076
A-045 A-079ST
A-059
-5 A-074
-5 A-025ST
-4
A-042
A-054A-104
-2
-4
12000
-5
11000
-3
A-088
-3
A-075
-2
-4
A-043
A-067
A-027
A-037
A-092
A-032
A-061 A-021
-3
A-024
A-106
A-082
A-068
A-105ST2A-102
A-022ST2
A-029
-1
A-083
-3
A-033
A-087
A-089 A-073
A-040
A-093
12000
13000
-3
-5
13000
A-101
A-090
A-044
-4
14000
11000
A-078
-2
10000
-5
10000
-2
-4
-3
-1A-095
A-111
8000
A-030
A-017
-4
A-097
A-070A-048
A-060
A-041
-4
A-085
A-108
A-084
A-062
-3
A-057
A-049
-2
A-094
A-046
A-110ST
A-047
A-100
A-053
-5
A-091
A-050
-5
Legend: (Production Analysis)
A-051
A-107
4000
-4
5000
-3
-4
-2
6000
A-077
-2
-1
7000
A-015 A-080
A-034
A-016
A-035
-4
A-099
-2
8000
9000
A-098
A-058
A-071
-5
9000
-5
x-position (relative distance)
factors computed using decline
type curve analysis
on early production.
Skin factors from
WPA are lower than
WT estimates.
These results represent the initial
completion (evaluated using earlytime production data).
Skin Factor Contour Plot
(1-increment Contours)
Arun Field (Indonesia)
A-109
7000
6000
5000
4000
3000
3000
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
y-position (relative distance)
khWT—khWPA Crossplot
Comparison of Flow Capacity (kh) from Well Test Analysis
versus Flow Capacity (kh) from Production Data Analysis
(Decline Type Curve Analysis) (Arun Field -- Indonesia)
2
3
4
5
10
10
10
10
5
5
10
10
estimates are
clearly higher than
khWPA estimates.
khWT estimates are
"current," khWPA
estimates are "initial."
Variation is systematic—decline type
curve analysis uses
earliest production
data for kh (and s)
estimates.
Flow Capacity (kh, md-ft)
from Well Test Analysis ( kh at Time of Well Test)
khWT
4
4
10
10
khWT = 5khWPA
3
3
10
10
Legend: khWT vs. khWPA
Comparison of kh from Well Test Analysis
versus kh from Production Data Analysis
(Decline Type Curve Analysis)
(Arun Field -- Indonesia)
2
2
10
10
2
10
3
4
5
10
10
10
Flow Capacity (kh, md-ft)
from Production Data Analysis (Early-Time Production Data)
sWT—sWPA Crossplot
Comparison of Skin Factor Estimates from Well Test Analysis
versus Skin Factor Estimates from Production Data Analysis
(Decline Type Curve Analysis) (Arun Field -- Indonesia)
estimates are
"current," sWPA
estimates are "initial."
Could argue that this
plot shows the "evolution" of the skin factor.
sWPA estimates should
be higher, tied to kh
estimation in decline
type curve analysis.
Skin Factor Estimate
from Well Test Analysis (Skin Factor at Time of Well Test)
sWT
-10
10
-8
-6
-4
-2
0
2
4
6
8
10
10
Virtually all cases of
the skin factor increase
as a function of time.
8
8
6
6
4
4
2
2
0
0
-2
-2
-4
-4
Legend: sWT vs. sWPA
-6
Comparison of s from Well Test Analysis
versus s from Production Data Analysis
(Decline Type Curve Analysis)
-8
-6
-8
(Arun Field -- Indonesia)
-10
-10
-8
-6
-4
-2
0
2
4
6
8
Skin Factor Estimate
from Production Data Analysis (Initial Skin Factor)
-10
10
Gas Reserves from Decline Type Curve Analysis
Comparison of Gas Reserves Computed from DeclineType Curve Analysis
(No Well Interference Case) Versus Date -- Arun Field, Indonesia
1,000,000
Legend: All Wells
Comparison of Computed Reserves
versus Date at Arun Field. All Results
based on production taken through
October 1997.
900,000
1977-80
Well
Completions
700,000
M ay-83
1981-83 A-047 (C-4-06)
Well
Completions
Jun-77
Sep-79
A-016 (C-3-04)
A-032 (C-2-03)
M ay-78
Nov -78
Sep-77
600,000
Jan-84
M ay-77 A-028
(C-2-04)
(C-3-09)
Nov -82A-050 (C-4-08)
Nov -79
A-017 A-024
(C-3-06)
Apr-80
Dec-78
A-022 (C-2-06)
A-034 (C-3-03) Apr-81
Jan-81
A-033 (C-2-07)
A-029 (C-2-16)
A-041 (C-3-15)
A-035
(C-3-05)
Jan-81
Apr-81
Aug-83
Oct-83
A-040 (C-2-15)
Apr-79
A-037 (C-2-01)
A-048 (C-4-09)
Feb-78A-030 (C-3-16)
M
ay-83(C-4-04)
A-049
Sep-92
1984-90
Well
Completions
A-105 (C-2-21)
1991-93
Well
Completions
A-015 (C-3-02)
500,000
400,000
A-046 (C-4-02)
Aug-82
Apr-83
A-027Oct-82
(C-1-08)
Apr-83
A-036 (C-1-02)
A-044
(C-1-09)
A-043
(C-1-16)
Dec-78
300,000
Post-1993
Well Completions
(Deviated and
Horizontal Wells)
M ar-87
Aug-93
A-068 (C-2-05)
Dec-86
A-109 (C-4-18)
Apr-92
Jul-85
Nov -87
Dec-87
Jun-91
A-060 (C-4-01)
Dec-87Sep-88
A-102 (C-2-19)
Jan-90
A-054 (C-1-07)
A-071 (C-3-11)
M ay-91
A-067 (C-1-15)
A-095
(C-3-14)
Jun-92
A-062 (C-4-03)
A-077 (C-3-01)
A-080 (C-3-13)
Sep-90
A-094 (C-4-13)
Jun-82
Oct-90
ay-92
A-104
(C-1-21)
MMar-92
Nov -86
M ay-91
Oct-91
Jul-95
A-081 (C-1-01)
Dec-84
Jun-93
Oct-87
A-042 (C-1-06)
Jul-91
A-085 (C-4-05)
A-103
(C-1-20)
A-100 (C-4-14)
A-059 (C-1-05)
Jan-86
M ay-87
Aug-90
A-093
(C-3-19)
A-089
(C-2-17) A-108 (C-3-20)
A-111 (C-3-18)
Aug-88
A-053 (C-4-07)
A-073 (C-2-14)
A-097 (C-3-08)
A-057 (C-4-10)
Dec-89
A-061
Nov -93
Nov
-86(C-2-10)
A-083
(C-2-13) Nov -91
A-075
(C-1-14)
Sep-88
Aug-90
M ar-91
Feb-91
Apr-87 Feb-88 Feb-89
A-079 (C-1-12)
A-099 (C-3-12) Apr-93
A-110 (C-4-12)
A-058 (C-3-10)
Jun-90M ar-91
A-076 (C-1-03) A-084A-090
Aug-91
(C-4-11)
M ar-92
M ar-85
(C-3-14)
A-074 (C-1-11)
A-088
Apr-83
M (C-1-13)
ar-91
A-070 (C-3-07)
A-078 (C-2-12)
A-091
(C-4-15)
A-107 (C-3-17)
A-082 (C-2-11)
A-098A-101
(C-2-18)
(C-1-19)
A-051 (C-4-16)
Dec-92
A-045 (C-1-04)
A-092 (C-1-17)
A-021 (C-2-09)
A-025 (C-2-08)
200,000
100,000
A-106 (C-2-20)
Feb-91
A-087 (C-2-02)
Well Completion Date (Year)
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
1988
1987
1986
1985
1984
1983
1982
1981
1980
1979
1978
1977
0
1976
Computed Gas Reserves, MMSCF
(No Well Interference)
800,000
Estimated Ultimate Recovery from Material Balance
Comparison of Material Balance Gas Reserves (EUR MB) Versus Date
Arun Field, Indonesia
1,000,000
Legend: All Wells
Comparison of Material Balance Gas
Reserves (EUR MB) versus Date at Arun
Field. All Results based on production
taken through October 1997.
1977-80
Well
Completions
800,000
1981-83
Well
Completions
700,000
600,000
Jun-77
1984-90
Well
Completions
Oct-82
Jan-81
Apr-79
-78
M ay-83Jan-84
A-016 Sep-77
(C-3-04) Nov
A-040 (C-2-15) A-044 (C-1-09)
A-030
(C-3-16)
Sep-79
Apr-80
Jan-81
A-050
(C-4-08)
A-017 (C-3-06)
A-028 (C-3-09)
M ay-83
A-047
(C-4-06)
A-032A-033
(C-2-03)
(C-2-07)
M ay-77
Nov -79A-035 (C-3-05)
A-046 (C-4-02)
Aug-82
A-015 (C-3-02)
M ay-78 A-034 (C-3-03)
A-027 (C-1-08)
Aug-93
A-024 (C-2-04)
Apr-83
A-109 (C-4-18)
Aug-83
Oct-83
Dec-78
A-043 (C-1-16)
Apr-81
Sep-92
A-048 (C-4-09)
A-049 (C-4-04)
A-025 (C-2-08)
Feb-78
Dec-87
Oct-87
A-037 (C-2-01)
A-105 (C-2-21)
Nov
-82
Apr-83
Jun-82
A-021 (C-2-09)
Dec-78
A-062(C-2-14)
(C-4-03)
A-073
Apr-81
Jul-85
A-022
(C-2-06)
A-036
(C-1-02)
A-042
(C-1-06)
A-029 (C-2-16)
M ay-87
A-041 (C-3-15)
A-054 (C-1-07) Dec-86
Sep-88
Jan-90
Apr-87
-86(C-2-10)
A-061
Apr-92
Jan-86 Nov
Oct-90 Jul-91M ar-92
A-060
(C-4-01)
Dec-84
A-077 (C-3-01)
A-080
(C-3-13) Jun-91
Jun-93
A-070
(C-3-07)
Aug-91
Dec-89
A-059 (C-1-05)
A-102 (C-2-19)
A-057
(C-4-10)
Nov -93
A-097 A-100
(C-3-08)
ar-85
(C-4-14)
A-085 (C-4-05)
A-053 M
(C-4-07)
Jun-92
M ay-91
A-108
(C-3-20)
A-095
(C-3-14)
Dec-92
Feb-89
Aug-88
A-098
(C-2-18)
M
ar-91
A-079
(C-1-12)
Sep-88
Jun-90
Sep-90
Apr-83
Nov -91
Aug-90
A-110
(C-4-12)
A-051 (C-4-16)
Dec-87
M ar-91
A-104
(C-1-21)
A-094
(C-4-13)
A-106
(C-2-20)
A-078
(C-2-12)A-081
M ar-87 A-075
(C-1-14)
A-092
(C-1-17)
(C-1-01)
Feb-91
A-045 (C-1-04)
A-099
(C-3-12)
A-084(C-2-11)
(C-4-11)
Nov -86 NovA-076
-87 (C-1-03) A-082
M
ay-92
A-067 (C-1-15)
Apr-93
A-091
(C-4-15)
MM
ar-91
ay-91
A-068 (C-2-05)
A-088 (C-1-13)
A-058 (C-3-10)
A-071 Feb-88
(C-3-11)
Oct-91
A-103 (C-1-20)
A-090
A-093(C-3-14)
(C-3-19) A-107 (C-3-17)
Aug-90
A-089 (C-2-17)
A-074 (C-1-11)
M ar-92
A-083 (C-2-13)
Feb-91A-101 (C-1-19)
500,000
400,000
300,000
200,000
100,000
1991-93
Well
Completions
Post-1993
Well Completions
(Deviated and
Horizontal Wells)
Well Completion Date (Year)
2000
1999
1998
1997
1996
1995
1994
1993
1992
1990
1989
1988
1987
1986
1985
1984
1983
1982
1981
1980
1979
1978
1977
1991
A-087 (C-2-02)
0
1976
Material Balance Gas Reserves (EUR MB), BSCF
900,000
Flow Capacity (kh) from Decline Type Curve Analysis
Comparison of Flow Capacity (kh) Computed from DeclineType Curve Analysis
(No Well Interference Case) Versus Date -- Arun Field, Indonesia
10,000
Legend: All Wells
Comparison of Computed Flow Capacity
(kh) versus Date at Arun Field. All Results
based on production taken through
October 1997.
9,000
Sep-92
Aug-93
A-105 (C-2-21)
A-109 (C-4-18)
7,000
1977-80
Well
Completions
6,000
1981-83
Well
Completions
1984-90
Well
Completions
1991-93
Well
Completions
5,000
M ay-92
Apr-92
A-103 (C-1-20)
A-102 (C-2-19)
4,000
Jan-81
3,000
Dec-87
M ar-87
A-040 (C-2-15)
Sep-77
Jun-91
A-062 (C-4-03)
A-068 (C-2-05)
Nov -87
Dec-87
A-071
(C-3-11)
Nov -86
A-067 (C-1-15)
A-059 (C-1-05)
A-017 (C-3-06)
A-095 (C-3-14)
Post-1993
Well Completions
(Deviated and
Horizontal Wells)
--These cases will
yield kh estimates
that are too high
because the well
model is vertical.
--Computed volume
estimates are
valid regardless
of well orientation.
Nov -93
Jul-95
Jun-93
A-110 (C-4-12)
A-111 (C-3-18)
A-108 (C-3-20)
M ay-91
Aug-90
Oct-90
Oct-83
A-093 (C-3-19)
Nov -78
A-041 (C-3-15)
M ay-83
M ar-92
A-083 (C-2-13)
M ay-91
Jan-81
A-085
(C-4-05)
A-049 Jan-84
(C-4-04)Dec-84
Jul-91 Jun-92
Jun-82
Jun-90
A-028 (C-3-09)
A-047 (C-4-06)
Sep-79
A-100 (C-4-14)
M
ar-91
Dec-78
Feb-91
M ay-87
Jan-90
Apr-80
A-094
A-035 (C-3-05)
Nov -82A-050 (C-4-08)
Nov
-91 (C-1-21)
A-104
A-097(C-4-13)
(C-3-08)
A-042Aug-82
(C-1-06)
A-082 (C-2-11)
Oct-91
Apr-83
M ar-92
M ay-78 A-032 (C-2-03)
M ar-91
M ay-83
Aug-83 A-053 (C-4-07)
Dec-78
Sep-90
Oct-82
A-091
(C-4-15)
A-029
(C-2-16)
A-088
A-061 (C-2-10)
M (C-1-13)
ar-91
Apr-83
Jul-85
A-080
(C-3-13)
A-033
(C-2-07)
Dec-89
Oct-87
Dec-92
A-027
(C-1-08)
Nov
-79
A-022
(C-2-06)
A-099
(C-3-12)
Jan-86 Dec-86
Aug-88
Jun-77
Aug-91
Apr-81
A-089
(C-2-17)
A-043
(C-1-16)
A-101 (C-1-19)Apr-93
A-024 (C-2-04)
A-090 (C-3-14)
A-046
(C-4-02)
A-048
(C-4-09)
M ay-77
A-025 (C-2-08)
A-081
(C-1-01)
Feb-78
A-044
(C-1-09)
A-092
(C-1-17) A-106 (C-2-20)
A-036
(C-1-02)
A-054 (C-1-07)
A-079 (C-1-12)
A-073 (C-2-14) Feb-89
Apr-87
A-060
(C-4-01)
A-034
(C-3-03)
A-057 (C-4-10)
A-075 (C-1-14)
A-016 (C-3-04)
Aug-90
A-098 (C-2-18) A-107 (C-3-17)
A-037 (C-2-01)
Apr-79
A-015 (C-3-02)
A-021 (C-2-09)
A-078 (C-2-12)
Feb-91
Apr-83
A-070 (C-3-07) Sep-88
A-084 (C-4-11)
A-030 (C-3-16)
Feb-88
Nov
-86
M ar-85
A-087 (C-2-02)
A-045 (C-1-04)
A-077 (C-1-03)
(C-3-01)
A-076
A-074 (C-1-11)
A-051 (C-4-16) A-058 (C-3-10)
Apr-81
2,000
1,000
Well Completion Date (Year)
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
1988
1987
1986
1985
1984
1983
1982
1981
1980
1979
1978
1977
0
1976
Computed Flow Capacity (kh), md-ft
8,000
G (Decline Type Curve)—EURMB Crossplot
Comparison of Gas Reserves from DeclineType Curve Analysis
(No Well Interference Case) versus Material Balance EUR
(Arun Field -- Indonesia)
4
5
6
7
10
10
10
10
7
7
10
10
crossplot
indicates excellent
agreement of computed results.
Gas Reserves from Decline Curve Analysis, BSCF
(No Well Interference Case)
G-EURMB
Legend: Computed OGIP vs. EUR MB
Comparison of Gas Reserves from Decline
Type Curve Analysis (No Well Interference
Case) versus Material Balance EUR MB.
(Arun Field -- Indonesia)
6
6
10
10
5
5
10
10
4
4
10
10
4
10
5
6
10
10
Material Balance Gas Reserves (EUR MB), BSCF
7
10
EURPI—EURMB Crossplot
crossplot shows excellent
correlation of results.
Verifies that these
analyses are consistent.
Gas Reserves from Productivity Index
EUR Technique (EURPI), BSCF
EURPI—EURMB
Comparison of Gas Reserves from Productivity Index EUR
versus Material Balance EUR
(Arun Field -- Indonesia)
4
5
6
7
10
10
10
10
7
7
10
10
Legend: Computed EUR PI vs. EUR MB
Comparison of Gas Reserves from Decline
Type Curve Analysis (Well Interference
Case) versus Material Balance EUR MB.
(Arun Field -- Indonesia)
6
6
10
10
5
5
10
10
4
4
10
10
4
10
5
6
10
10
Material Balance Gas Reserves (EUR MB), BSCF
7
10
Well Performance Analysis in a Multiwell
Gas Condensate Reservoir—
Arun Field, Indonesia
Presented at
SPE Advanced Technology Workshop
Well Testing in Gas Condensate Reservoirs
30 September- 1 October 1999, Houston, TX.
T. Marhaendrajana, Texas A&M University
N.J. Kaczorowski, Mobil E&P (U.S.)
T.A. Blasingame, Texas A&M University
Well Test Analysis: Examples (extra)
Well C-IV-11 (A-084)—Test Date: 5 Jan. 1992
Multiwell interference effects.
Well C-IV-11 (A-084)—Test Date: 4 May 1992
Radial composite effects.
Multiwell interference effects.
psi
Functions,
Pseudopressure
Pseudopressure Functions,
psi
Example 3: Log-log Summary Plot
Well C-IV-11
(A-084)
[TestDate:
Date:55 January
January 1992]
Well C-IV-11
(A-084)
[Test
1992]
3
10
Raw data
Corrected
Improvement on
pressure derivative.
2
10
1
10
Closed boundary
atReservoir
150 ft? Model
Infinite-acting
(Does
not include non-Darcy
(includes
non-Darcy
flow). flow)
0
10
-4
10
-3
10
-2
10
-1
10
0
10
Effective Shut-in Pseudotime, tae, hrs
Effective
shut-in pseudotime, hrs
1
10
Example 3: Horner (Semilog) Plot
C-IV-11
(A-084)[Test
[TestDate:
Date: 55January
1992]
WellWell
C-IV-11
(A-084)
January
1992]
Shut-in
Pseudopressure, ppws , psiapsia
Pseudopressure,
Shut-in
2100
2000
1900
1800
1700
1600
1500
1400
Raw data
Corrected
1300
1200
3
10
2
10
1
10
Horner Pseudotime, ( ta+tpa)/ta (tpa=tp=1.62 hr), hr
Horner pseudotime, hrs (tp = 1.62 hr)
0
10
Example 3: Muskat Plot (single well pavg plot)
Shut-inpseudopressure,
Pseudopressure, ppws , psia psia
Shut-in
C-IV-11
(A-084)[Test
[Test Date:
Date: 55January
1992]
WellWell
C-IV-11
(A-084)
January
1992]
1922
pp,bar = 1920 psia
1920
Onset of boundary
dominated flow.
1918
1916
"Transient flow"
1914
1912
1910
0
5
10
dp pws
dppws
/d/dtta, ,psi/hr
psi/hr
a
15
20
Example 3: "Well Interference" Plot (radial flow only)
Well
C-IV-11
[TestDate:
Date:5 January
5 January
1992]
Well
C-IV-11(A-084)
(A-084) [Test
1992]
25
Intercept is used to
calculate permeability.
Slope is used in the
pressure correction.
15
(p ')
ae
p t
(pp')tae
, psi
20
10
5
0
Presence of multiwell
interference effects is unclear
-5
0
5
10
15
2
ttaa/2/tae, hrs
tae
20
25
psi
Functions,
Pseudopressure
Pseudopressure Functions,
psi
Example 4: Log-log Summary Plot
Well Well
C-IV-11
(A-084)
[Test
May1992]
1992]
C-IV-11
(A-084)
[TestDate:
Date: 4
4 May
3
10
Raw data
Corrected
Improvement on
pressure derivative.
2
10
Condensate banking
region.
1
10
Infinite-acting Reservoir Model
Closed(Does
boundary
at
197
ft?
Higher
mobility
not include
non-Darcy
flow)
(includes non-Darcy flow).
region.
0
10
-4
10
-3
10
-2
10
-1
10
Effective Shut-in Pseudotime, t , hrs
0
10
ae
Effective shut-in pseudotime,
hrs
1
10
Example 4: Horner (Semilog) Plot
C-IV-11
(A-084)[Test
[Test Date:
Date: 44May
1992]
WellWell
C-IV-11
(A-084)
May
1992]
Shut-in
Pseudopressure, ppws , psiapsia
Pseudopressure,
Shut-in
1950
1900
1850
1800
1750
Condensate banking
region.
Higher mobility
region.
1700
1650
1600
Raw data
Corrected
1550
1500
3
10
2
10
1
10
Horner Pseudotime, ( ta+tpa)/ta (tpa=tp=1.63 hr), hr
Horner
pseudotime, hrs (tp = 1.63 hr)
0
10
Example 4: Muskat Plot (single well pavg plot)
Shut-inpseudopressure,
Pseudopressure, ppws , psia psia
Shut-in
C-IV-11
(A-084)[Test
[Test Date:
Date: 44May
1992]
WellWell
C-IV-11
(A-084)
May
1992]
1884
pp,bar = 1882.8 psia
1882
1880
Onset of boundary
dominated flow.
1878
1876
"Transient flow"
1874
1872
1870
0
5
10
dp pws
dppws
/d/dtta, ,psi/hr
psi/hr
a
15
20
Example 4: "Well Interference" Plot (radial flow only)
Well
C-IV-11
[TestDate:
Date:
4 May
1992]
Well
C-IV-11(A-084)
(A-084) [Test
4 May
1992]
40
Intercept is used to
calculate permeability.
Slope is used in the
pressure correction.
ae
p'), tpsi
(pp')(tpae
30
20
10
(pp')tae >0, no clear indication of
multiwell interference effects.
0
0
5
10
15
2
ta / tae
ta /2tae, hrs
20
25
30