View
2
Download
0
Category
Preview:
Citation preview
1
SACROC CO2 Flood
Project Challenges: Past,
Present, and Future
Presented at the 19th Annual CO2 Flooding Conference
December 11-13, 2013
Midland, Texas
1
SACROC is in the
Kelly-Snyder Field,
largest of a chain of
Canyon Reef Fields
making up the
Pennsylvanian
Aged Horseshoe
Atoll
2
4
SACROC Unit Information
• Field discovery 11/1948
• Productive area: 49,980 acres
• Formation: Canyon Reef
• OOIP: 2,800 MMSTBO
• Oil column thickness: up to 900 ft in
Platform
• Average depth: 6800’
• Discovery pressure: 3122 psi
• Oil gravity: 42 API
• HC GOR:
– Original: 1000 Scf/Stbo
– CO2 Flood: 2600 Scf/Stbo
• Rich gas, 230 Bbls NGL/Mmscf
HC gas
• Total CO2 Flood Gas GOR:
28,000 Scf/Stbo
• 11/2013 Production & Injection: – 31,900 BOPD
– 18,900 BPD NGL
– 1,040 MMSCFID CO2 (90% Recycled)
3
1,000
10,000
100,000
1,000,000
10,000,000
1/1/1945 1/1/1955 1/1/1965 1/1/1975 1/1/1985 1/1/1995 1/1/2005 1/1/2015
Dai
ly R
ate
s (B
OP
D, B
WP
D, B
WIP
D, C
O2
Pro
du
ctio
n &
Inje
ctio
n M
SCFD
)
SACROC Unit Performance HistoryBOPD
BWPD
CO2 Recycle (MSCFD)
BWIPD
CO2 Injection (MCFID)
4
11/1948: Field discovery
9/1954: Center Line Water Injection begins
Late 1971: Pattern waterflood begins
1/1972: CO2 injection begins
3/1974: Peak oil rate (215,000 Bopd)
1975: 20-acre infill drilling, 40-acre 5-spot development
Cumulatives:
Oil Prod: 1.36 Bstbo
CO2 Inj: 4.92 Tcf
CO2 Recovery: 2.99 Tcf
P1AP1B
P3 North
P3 SOUTH
P4
SACROC 1974 Center Line CO2 Injection Test Patterns
SACROC Cumulative CO2
Injection to 1/1/1975
•Two 40-acre 5-spots were
drilled in in a watered out
area in the Center Line
Area
•Definitive 200 BOPD oil
response occurred
•CO2 injected for 10
months, 16% HCPV CO2,
1.5% OOIP EOR
5
1
10
100
1000
10000
100000
1/1/1973 1/1/1974 1/1/1975 1/1/1976 1/1/1977
BO
PD
, BW
PD
, HC
MSC
FD, C
O2p
MSC
FD, B
WIP
D,
CO
2i M
SCFI
D
SACROC Unit Center Line CO2 Test AreaBOPDBWPDHC MSCFDCO2 MSCFDBWIPDCO2 MSCFID
100
1000
10000
100000
1/1/1970 1/1/1975 1/2/1980 1/1/1985
Da
ily R
ate
s (B
PD
, MSC
FD)
BOPD
BWPD
CO2 MSCFD
BWIPD
CO2 MSCFID
SACROC 4-Pattern Area CO2 Flood Pilot
Cumulative CO2 Injection
Bubble Map through January,
1996
• Pilot conducted in south part of Unit ahead of the CO2 injection expansion
into the south of the Unit
• Pilot made up of four ~160-acre inverted 9-spot patterns
• 2000 BOPD+ of definitive oil response
• EOR was 10% of OOIP after 30% HCPV CO2 injection
• However, oil influx from outside project area complicates analysis; IWR<1.0
Water
injection
from 1973
to 1981
CO2-WAG
injection
from 1981
to 1986
6
Norflood
SW Bank
Center Line
SACROC Early 1997 CO2 Injection Focusing on Center Line,
Norflood, & SW Bank Redevelopment Projects
• Pennzenergy suspected that SACROC
hadn’t been effectively CO2 flooded
– Other West Texas projects beginning CO2
injection in the 1980’s and 1990’s had
exhibited significant CO2 Flood EOR
Wedges
– SACROC’s CO2 injection had been
conducted using high WAG ratios,
sometimes below MMP
• Three focused CO2 flood test areas were
initiated:
– Norflood
• Focused on low permeability Middle
Canyon
– Southwest Bank
• Focused CO2 injection in lower
permeability reservoir
– Center Line
• Focused 40-acre 5-spot pattern
development
7
Initial KM CO2 Flood Redevelopment
• KM Purchased SACROC in
2000
• Expanded upon Pennzenergy’s
successful Center Line CO2
flood project
• KM expanded its CO2 pipeline
infrastructure in 2003 by
installing the Centerline Pipeline
to deliver another 300 MMSCFD
to the SACROC area and
beyond
8
McElmo Dome
St. John’s
Yates
Sacroc
Katz
CO2 Pipelines
Doe Canyon
Year Project
1996: Center Line 1 & 2 Expansions (CL1 & CL2)
2001: Center Line 3 (CL3)
2002: Center Line 4 (CL4)
2002: Center Line 5 (CL5)
2003: Bull’s Eye (BE)
2004: Center Ring 1 (CR1)
2005: Center Ring 2 (CR2)
2007: Southwest Center Line 1 & 2 (SWCL1 & 2)
2008: Southwest Center Line 3 (SWCL3)
2008: Gilligan’s Island (GI)
2008: South Platform (SP)
Platform development was deferred until all
of the Central Plain areas were completed.
CL
1
CL3
CR1
CR2 GI
SWCL
1 & 2
BE
SP
SACROC CO2 Flood Redevelopment Project Areas 1996-2008
CR2
CR2
9
1996-2008 CO2 Flood Project Area Contribution to
Total Unit Production
10
0
5000
10000
15000
20000
25000
30000
35000
40000
1/1/1995 1/1/2000 1/1/2005 1/1/2010
Oil
Rat
e (
BO
PD
)
Gilligan's Island
South Platform
Southwest Center Line
CR 2
CR 1
Bullseye
CL 5
CL 4
CL 3
CL 1 & 2
SACROC Unit Total
Platform CO2 Flood Development
• SACROC Platform Area has
the thickest pay in all of
SACROC
– OOIP: 951 MMSTBO
– Area: 5700 acres, 145 patterns
• Complex, Highly
Heterogeneous Reservoir
– Some Dual, Triple injection well
completions used to better
distribute CO2 injection
11
37-11 Core
Location
Perforating for Conformance - Intervals
Intervals
Cisco
Green Zone
MCN3
Lower Middle Canyon
Descriptions
Moderate matrix permeability, unconnected fractures result in fast processing rates in some areas, porosity lenses not well connected.
Thick and continuous with good matrix permeability. Characterized by highly permeable features that short circuit sweep through matrix.
High permeability matrix, good continuity, excellent sweep.
Layered and continuous. Low porosity and matrix permeability. Few fractures or high permeability features.
SACROC Platform Pay Zone Intervals
12
SACROCwestside
SACROCsouth and eastside
SACROCupper Green Zone
Platform Area Green Zone
Navassa Island Modern Day Green Zone Analog Karsted Core Sample
13
P1A & P1B 2009 Initial Platform CO2 Flood Project Areas
• Expanding CO2 Flood into
the Platform meant
confronting severe CO2
channeling issues
– Several cases of CO2
breaking through within
hours of starting CO2
injection
• IDEA (Infill Development
Experimental Area)
– 10-acre infill drilling & conversion
project was implemented to create
20-acre 5-spot patterns
– Objective was to increase recovery
by connecting up discontinuous pay
and allow faster processing of lower
permeability layers
• Unfortunately the infill
drilling also connected up
the high permeability
layers/channels
14
10-acre IDEA Producers
IDEA Conversions to
Injection
P1A P1B
CO2 Channeling Issues
• Early CO2 channeling issues resulted in several patterns having to be shut-in
– Cross-linked polyacrylate gel treatments successfully controlled many of the
problems (except in the most extreme cases)
– The long pump times required for placing the polymer treatments resulted in
substantial production downtime
15
Injecting Polymer
Polymer Finished
Shut In after BT
RTP
RTI CO2
Confirmed Channel
Suspected Channel
IDEA Area Map Showing Channels Indicated by Polymer Testing
P2 Project Design Changes
• Pre-Injection Polymer
Treatments were pumped
– Pumping polymer before
beginning CO2 injection
avoided significant production
downtime
• Where economically justified,
three injection well completions
were implemented to better
distribute CO2 injection
• Horizontal producer was drilled
on east side of project
– Replaced drilling 5 vertical
wells
16
37-11
SACROC Pattern 37-11 Triplet
Injection Completion
CO2 Water CO2 Water CO2 Water
Cisco
Green
Zone
Middle Canyon
Completion
OOIP
(MSTBO)
2013
Average
Injection
(RBPD)
Processing
Rate
(%HCPV/Yr)
Cisco 3255 5452 41%
GZ/UMCN 5845 6242 26%
LMCN 3121 1055 8%
Total 12221 12750 25%
17
SACROC Pattern 37-11
18
0
2000
4000
6000
8000
10000
12000
14000
16000
18000
0
100
200
300
400
500
600
700
800
900
Jan
-12
Jul-1
2
De
c-12
Jul-1
3
De
c-13
CO
2 P
rod
uct
ion
(MS
CFD
), W
ate
r P
rod
uct
ion
(BW
PD
)
Oil
Ra
te (
BO
PD
)
Actual BOPD
Actual BWPD
Actual CO2p MCFD
0
4000
8000
12000
16000
20000
24000
28000
32000
36000
Jan
-12
Jul-1
2
De
c-12
Jul-1
3
De
c-13
CO
2 In
j R
ate
(M
SC
FD)
Total Pattern CO2 Inj Rate
Lower Middle Canyon
Green Zone
Cisco
SACROC
Platform
Oil Rate
Tests
12/2013
19
Horizontal Producers
20
Horizontal
Producing
Well
• Drilling a horizontal producer replaced drilling
5 vertical wells
• Well was completed using 18 cross-
linked gelled acid stages
• Being able to drill horizontal producers will
reduce the development cost of expanding
the CO2 flood project into the thinner patterns
along the edge of the field
1
10
100
1,000
10,000
100,000
Dai
ly R
ate
s
SACROC Horizontal Producer 30-22H
Oil (BBLS)
Water (BBLS)
Gas (MCF)
Sum of Offset CO2 Injection (MSCF)
Lower MCN Horizontal Injection Completions
• Concerns over Lower MCN
vertical well drilling costs,
reservoir processing rates led to
approving 6 horizontal injection
wells in the P3 South and P3
North CO2 Flood Project Areas
– Vertical well Lower MCN
processing rates estimated to
be <10% HCPV/yr
– Multi-stage acid fractured
Lower MCN processing rate
expected to be >25% HCPV/yr
• All 3 of the P3 South wells have
be successfully drilled and
completed
– 11-16H began CO2 injection on
11/27/13; currently injecting
25,000 MSCFD (30% HCPV/yr)
21
11-16H
1996-2013 CO2 Flood Project Area Contribution to
Total Unit Production
22
Future SACROC CO2 Flood Development
4-Component Strategy:
– Exploit Transition Zone
– By-Passed Redevelopment
– Edge Pattern Development
– Reassessment of Infill Development Potential
23
SACROC South Shore Transition Zone Test
Patterns 296-1 and 296-2
24
SACROC South Shore Transition Zone Test Patterns 296-1 and 296-2
10
100
1000
10000
100000
7/1/2011 12/30/2011 6/30/2012 12/29/2012 6/30/2013
Rat
e (B
PD
, M
SCFD
)
SACROC Unit Pattern PATS 296-1 & 296-2
Actual MCFID
Actual BWPD
Actual CO2p MCFD
Actual BOPD
Bypassed MCN Pay Horizontal Injector 155-18H
25
P1A
P1B
PAT 100-1
PAT 101-1
PAT 102-2
PAT 102-3
PAT 103-1
PAT 104-1
PAT 105-2
PAT 106-1
PAT 106-3
PAT 107-1
PAT 107A-1
PAT 109-1A
PAT 109-4
PAT 109-5A
PAT 110-2
PAT 110-3
PAT 111-1
PAT 111-4
PAT 112-1
PAT 112-3
PAT 113-3A
PAT 114-1
PAT 115-1GAP
PAT 115-2
PAT 115-4
PAT 115-5GAP
PAT 116-1
PAT 116-3 PAT 116-7GAP
PAT 117-1
PAT 117-2PAT 117-3
PAT 117-4
PAT 118-1
PAT 118-10
PAT 118-11
PAT 118-12
PAT 118-2
PAT 118-28PAT 118-3
PAT 118-4AGAP
PAT 118-5PAT 118-6
PAT 118-7
PAT 118-8
PAT 119-1
PAT 119-2PAT 120-1
PAT 120-2
PAT 121-1PAT 121-2
PAT 121-3
PAT 121-4
PAT 121-5
PAT 122-1PAT 122-2
PAT 122-3
PAT 123-1PAT 123-2
PAT 123-4PAT 123-6
PAT 124-11
PAT 124-12
PAT 124-13PAT 124-15
PAT 124-7PAT 125-5
PAT 127-1
PAT 127-5
PAT 128-X
PAT 128-Y
PAT 129-2PAT 129-4A
PAT 132-1PAT 132-2
PAT 133-1
PAT 136-3
PAT 136-7
PAT 136-X
PAT 136-Y
PAT 136-Z
PAT 137-X
PAT 138-1
PAT 138-13
PAT 138-2
PAT 138-3
PAT 138-5
PAT 138-6A
PAT 138-7A
PAT 138-8
PAT 139-2APAT 139-6
PAT 140-5PAT 140-6
PAT 141-1
PAT 141-2PAT 141-3
PAT 141-4
PAT 142-1PAT 142-3
PAT 142-8PAT 142-9
PAT 143-1
PAT 143-2
PAT 143-3GAP
PAT 143-4
PAT 144-1
PAT 144-2
PAT 145-1A
PAT 145-4
PAT 146-1
PAT 146-2
PAT 146-3
PAT 146-4
PAT 147-1
PAT 147-2
PAT 147-3
PAT 147-4
PAT 147-5PAT 147-6
PAT 147-7
PAT 147-8
PAT 148-1
PAT 148-11
PAT 149-1
PAT 150-1PAT 150-4GAP
PAT 150-5
PAT 151-1PAT 152-3A
PAT 152-5
PAT 153-1
PAT 153-12
PAT 153-2
PAT 154-2
PAT 155-2
PAT 155-6
PAT 155-8 PAT 155-9
PAT 156-2PAT 156-3
PAT 156-4GAP
PAT 156-6
PAT 157-1
PAT 157-6
PAT 158-5
PAT 159-1
PAT 159-3
PAT 159-5
PAT 160-4
PAT 160-5
PAT 163-2
PAT 163-3
PAT 164-1
PAT 165-2PAT 166-1
PAT 166-10A
PAT 166-11
PAT 166-13
PAT 166-14
PAT 166-21
PAT 166-2GAP
PAT 166-3
PAT 166-6
PAT 166-8
PAT 167-6GAP
PAT 167-8
PAT 167-9PAT 168-5
PAT 169-1 PAT 169-3
PAT 169-5
PAT 170-1
PAT 170-2
PAT 171-1
PAT 171-2
PAT 171-4
PAT 172-1
PAT 172-6GAP
PAT 172-7
PAT 173-10
PAT 173-11
PAT 173-13
PAT 173-2
PAT 173-3
PAT 173-9GAP
PAT 174-1
PAT 174-2PAT 174-3
PAT 174-4
PAT 175-2
PAT 176-5
PAT 176-8GAP
PAT 177-3PAT 177-4A
PAT 177-5
PAT 177-6
PAT 178-1PAT 178-2
PAT 178-3GAP
PAT 178-4
PAT 179-1PAT 179-2
PAT 179-5GAP
PAT 179-6
PAT 180-7
PAT 180-8
PAT 181-3
PAT 184-1
PAT 187-1
PAT 188-2
PAT 188-5
PAT 188-6
PAT 189-1
PAT 190-2
PAT 198-1
PAT 198-7
PAT 199-1
PAT 199-7
PAT 200-1
PAT 200-7
PAT 202-1
PAT 203-6
PAT 203-7
PAT 203-8
PAT 203-9
PAT 204-2 PAT 204-7
PAT 205-2
PAT 206-1
PAT 206-5A
PAT 206-6
PAT 206A-7
PAT 207-5
PAT 208-2
PAT 208-5
PAT 210-5
PAT 210-6
PAT 210-8
PAT 211-2
PAT 212-2
PAT 212-4PAT 212-5
PAT 213-4
PAT 213-5PAT 214-3
PAT 215-2
PAT 215-5
PAT 215-6PAT 215-7
PAT 216-5PAT 216-6
PAT 217-1GAP
PAT 217-7
PAT 217-8PAT 217-9
PAT 220-5
PAT 221-1
PAT 221-2PAT 221-3
PAT 221-4
PAT 223-1GAP
PAT 223-2PAT 224-1
PAT 224-2GAP
PAT 225-10
PAT 225-11PAT 225-3A
PAT 225-8
PAT 227-5
PAT 228-5
PAT 228-6
PAT 228-7
PAT 229-1
PAT 229-2AGAP
PAT 230-4
PAT 232-2
PAT 233-2
PAT 234-1
PAT 256-2
PAT 257-4
PAT 258-1PAT 259-1
PAT 259-2A
PAT 260-5
PAT 261-1A
PAT 261-2
PAT 261-6
PAT 261-7A
PAT 262-7
PAT 262A-1A
PAT 262A-2A
PAT 263-1A
PAT 263-9
PAT 265-2A
PAT 266-1A
PAT 267-3
PAT 268-2A
PAT 268-4
PAT 269-1A
PAT 269-3
PAT 270-1
PAT 270-3
PAT 271-1A
PAT 271-4
PAT 272-1
PAT 272-4
PAT 273-1A
PAT 273-4
PAT 274-1
PAT 274-2
PAT 293-2
PAT 299-1A
PAT 299-4APAT 303-4
PAT 44-1
PAT 44-4
PAT 45-1PAT 45A-1
PAT 46-13PAT 46-14
PAT 46-16
PAT 46-6
PAT 50-2A
PAT 51-1A
PAT 51-2PAT 51-4A
PAT 51-8
PAT 52-2APAT 53-2A
PAT 54-1APAT 54-2
PAT 54-3PAT 54-4
PAT 56-10APAT 56-28PAT 56-3APAT 56-5APAT 56-7APAT 56-9A
PAT 57-1PAT 57-2A
PAT 57-3PAT 57-4 PAT 60-1PAT 60-2
PAT 60-3APAT 60-4A
PAT 61-2
PAT 61-5
PAT 61-9
PAT 64-4
PAT 65-1PAT 65-10
PAT 65-2APAT 65-3
PAT 65-5
PAT 65-6
PAT 65-9
PAT 67-1A
PAT 67-2PAT 67-3A
PAT 67-4A
PAT 67-5A
PAT 67-6
PAT 67-9
PAT 68-7
PAT 69-1APAT 69-2
PAT 69-3APAT 69-4A
PAT 70-1PAT 70-3A
PAT 70-8
PAT 71-1
PAT 71-3PAT 71-4
PAT 71-8
PAT 72-1
PAT 72-2
PAT 72-3
PAT 72-4
PAT 72A-7
PAT 73-1PAT 73-2
PAT 73-3 PAT 73-4
PAT 74-10
PAT 74-11
PAT 74-2
PAT 74-9
PAT 75-16PAT 75-2
PAT 75-3PAT 75-4
PAT 75-5
PAT 75-6
PAT 75-7
PAT 75-8
PAT 76-1
PAT 77-1 PAT 77-2
PAT 77-3
PAT 77-4
PAT 77-8
PAT 79-5
PAT 79-6PAT 79-7
PAT 81-1PAT 81-2
PAT 81A-1PAT 82-2
PAT 84-3PAT 85-1
PAT 85-2
PAT 85-3 PAT 85-4
PAT 85-5
PAT 85-6
PAT 85-7
PAT 86-11
PAT 86-15A
PAT 86-2
PAT 86-3A
PAT 86-4
PAT 86-5A
PAT 86-9APAT 87-2
PAT 87-4PAT 88-3
PAT 89-1A
PAT 89-2
PAT 90-3
PAT 90-4A
PAT 91-11
PAT 91-12PAT 91-13
PAT 91-14 PAT 91-15
PAT 91-3GAP
PAT 91-4
PAT 91-5
PAT 91-9GAP
PAT 92-10
PAT 92-12
PAT 92-1GAP
PAT 92-9
PAT 93-3
PAT 94-2
PAT 94-3
PAT 94-5
PAT 96-1
PAT 98-1
PAT 99-4
PAT 99B-2A
26
Center Ring 1 & 2 Bypassed Pay
12-Horizontal Well Redevelopment Area
Potential CO2 Flood Expansion Patterns
27
• Although pay quality is less favorable, significant
OOIP (>500 MMSTBO) exists outside the active
or currently proposed project areas
• Challenges to developing these patterns include
– Few if any available well bores
– Insufficient pay volume to economically justify
traditional pattern development
• Potential solutions being evaluated include:
– Multi-stage fracture stimulated horizontal
producers and injectors
– Including Transition Zone reservoir volumes in
recovery forecasts
– Identifying areas that water flooded well,
indicating they will respond well to
CO2 injection
IDEA versus Offset Project Recoveries
28
0.000 0.000
0.000
0.012
0.019
0.009
0.074
0.0380.094
0.053
0.039
0.025
0.025
0.0730.042
0.0320.041 0.064
0.0370.037
0.024 0.0090.004
0.050 0.0350.043
0.098 0.0780.043
0.010
0.0020.007
0.000
0.001
0.0040.002
0.000
0.000
0.0020.0090.0340.029
0.0230.025
0.0090.016
0.005
0.0310.0620.027
0.0340.013
0.0120.0200.018
0.0180.013
0.0180.010
0.194 0.153 0.030
0.0160.0100.012
0.071 0.077
0.0390.061 0.0320.0090.014
0.033 0.033 0.040 0.0570.019
0.030
0.057 0.0350.0200.0050.052 0.056
0.0290.023
0.0470.057
0.017
0.0350.055
0.0690.087
0.035
0.060
0.105
0.073
0.099
0.069
0.081
0.107
0.104
0.096
0.058
0.067
0.0650.032
0.047
0.040
0.040
0.0240.013
0.065 0.122 0.051
0.0500.037 0.005
P1A
P1B
P3 North
P3 SOUTH
P4
PAT 14-4
PAT 16-2
PAT 16-4 PAT 16-6
PAT 16-7
PAT 16-8
PAT 18-2M
PAT 18-4PAT 18-4APAT 18-4M
PAT 18-6APAT 18-6M
PAT 18-7A
PAT 18-7M
PAT 18-8PAT 20-4PAT 20-5
PAT 20-6PAT 20-8
PAT 21-4PAT 21-5
PAT 22-5
PAT 22-6
PAT 23-1
PAT 23-2
PAT 24-1PAT 24-3
PAT 24-4PAT 24-8
PAT 25-1
PAT 25-2APAT 25-3
PAT 25-4
PAT 26-1APAT 26-2A
PAT 26-3ALPAT 26-3AS
PAT 26-4A
PAT 26-5
PAT 26-6
PAT 26-7APAT 26-8
PAT 27-1APAT 27-2A PAT 27-3APAT 27-4
PAT 27-5APAT 27-6A
PAT 27-7A PAT 27-8APAT 27-8B
PAT 28-1A PAT 28-2APAT 28-3A
PAT 28-4 PAT 28-5APAT 28-6A
PAT 28-7APAT 28-7B
PAT 28-8APAT 28-8B
PAT 29-1
PAT 29-2
PAT 29-3 PAT 29-4
PAT 29-5 PAT 29-6
PAT 29-7
PAT 29-8
PAT 30-1
PAT 30-11A
PAT 30-12
PAT 30-13PAT 30-18
PAT 30-2APAT 30-2B
PAT 30-6PAT 30-8
PAT 31-13
PAT 32-14
PAT 32-16
PAT 32-17
PAT 32-24ALPAT 32-24ASPAT 32-3APAT 32-3B
PAT 32-4APAT 32-4B
PAT 32-5ALPAT 32-5AS
PAT 32-9A
PAT 33-10
PAT 33-1ALPAT 33-1ASPAT 33-1B
PAT 33-2PAT 33-2A
PAT 33-3APAT 33-3BPAT 33-4
PAT 33-5APAT 33-5B
PAT 33-7APAT 33-7B
PAT 33-9
PAT 34-5 PAT 34-6A PAT 34-7A
PAT 34-8
PAT 34-8APAT 34-8B
PAT 35-1 PAT 35-2A
PAT 35-3PAT 35-3A PAT 35-4APAT 35-4BLPAT 35-4BS
PAT 36-A1PAT 36-B2A PAT 36-C3A PAT 36-D4PAT 36-D4A
PAT 36-D4B
PAT 37-1PAT 37-11PAT 37-11APAT 37-11BPAT 37-2A PAT 37-3A
PAT 38-1APAT 38-2
PAT 38-3APAT 38-4
PAT 39-2A
PAT 39-3APAT 39-4
PAT 39-9PAT 40-1A
PAT 40-2
PAT 40-3A
PAT 40-4A
PAT 40-5
PAT 40-6
PAT 40-7
PAT 40-8
PAT 41-1
PAT 41-2
PAT 41-4
PAT 42-1
PAT 42-2
PAT 42-3
PAT 43-1
PAT 48-3
PAT 49-1
PAT 49-2A
PAT 49-3A
PAT 49-4A
PAT 49-5A
PAT 49-6A
PAT 49-7
PAT 49-8 PAT 55-1A
PAT 55-2A
PAT 55-3ALPAT 55-3AS
PAT 55-4A
PAT 58-1A
PAT 58-2A
PAT 59-1PAT 59-1A
PAT 59-2A PAT 59-3APAT 62-15
PAT 62-1APAT 62-1B PAT 62-3APAT 62-8
IDEA Pattern recoveries
to date are around 3%
higher than in offset
areas
Although initially plagued
by CO2 breakthrough
problems, the combination
of 10-acre infill drilling
polymer gel and
specialized cement
squeeze treatments may
have resulted in high
efficiency patterns Some improved recovery due to
targeting geologically isolated
“Green Zone” Pinchouts
Additional infill wells have been
recommended
Summary
• CO2 flooding has presented SACROC’s operators with engineering
challenges since 1972
• Focused CO2 flood development projects, injecting large pore volumes
of CO2 of 80-100% of the HCPV, have resulted in significant
incremental EOR
• Mitigating heterogeneity issues through the innovative application of
polymer, cementing, and horizontal well technologies has been critical
to CO2 flood performance success
• Continued CO2 flood development of the lower permeability bypassed
pay and reservoir around the edges, along with focused
vertical/horizontal infill drilling applications within existing flood areas,
will challenge SACROC engineers & geoscientists for many years to
come
Big fields keep getting bigger! 29
Recommended