Building & Expanding the Ula WAG

Building & Expanding the Ula WAG

FORCE WAG Conference18 March 2009Becki van Gestel, BP Norge AS

Ula Field

• Overview

• Field History

• Current WAG Scheme

• Future WAG Scheme

• Summary

Overview Field History Future WAG Summary

Ekofisk

Tambar

ULA

Gyda

Aberdeen

Stavanger

London

Ula

Ekofisk

Emden

Teeside

Current WAG

Ula Facts

• Ula Ownership:

− 80% - BP (operator)

− 20% - DONG E&P Norge AS

• On stream: 1986

• Tambar Field tie-in: 2001

• Blane Field tie-in: 2007

• STOOIP

− ~1 billion stb (160 mill Sm3)

• Produced as of 01-01-09

− 436 mmstb oil (70 mill Sm3)

ULA

TAMBAR

Living Q

DrillingProduction

BLANE

Overview Field History Future WAG SummaryCurrent WAG

Blane Tambar

Ula Structure

• Elongated four-way salt induced dip closure

• Reservoir dips between 0 and 10o

− Lower dips at the crest and to the south (0 to 5o)

• A NW-SE fault system bisects the structure

• Shallower oil-water contact in west flank

• Reservoir depth: 3350-3800m

TAMBAR

EF OWC - 3800m

NF OWC - 3560m

WF OWC - 3500m

NE

SW

NESW

Unit 1

Unit 2+3Triassic

3350

3500

3650

3800

3200

NESW

Unit 1

Unit 2+3Triassic

3350

3500

3650

3800

3200


Reservoir Units

~ 1

00

m

Ula

F

orm

ati

on

Perm (mD)

Upper Jurassic, shallow marine sandstones

Baffle between

Unit 1A2 & 1A3

Capable of holding

>1000 psi (70 bar)

<5cm

CurrentWAG

Unit 1Hor.

Producers

FutureUnit 3WAG

Injectors

1A11A21A31B

1-10

1-20

2-25

5-100

3

20-4000

20-200

10-100

2

2-15

4390

4400

4410

4420

4430

4440

4450

4460

4470

4480

4490

4500

DE

PTH

ME

TR

ES

3500

3510

3520

3530

3540

3550

3560

TVD

ME

TR

ES

SW_2

V/V1 0

FluidsA16AInitial After WF Future

Sorw ~ 35-50%

Sorm ~ 5-10%

Wat

er

Gas

/Wat

er

Oil

Ula StratigraphyOverview Field History Future WAG SummaryCurrent WAG

Baffle in lower Unit 2

Capable of holding >35

psi

0.00.40.71.11.41.82.1

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WCUT

WI

sta

rts

WA

G

star

ts

Tam

bar

tie

d-in

Mor

e W

AG

conv

ersi

ons

Onl

ine

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ter

disc

over

y

arrested decline

WA

G o

il in

al

l W

AG

pr

oduc

ers

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it 1

p

rod

uct

ion

star

ts

Sha

rp d

eclin

e

WA

G S

tudi

es

140

0

250

0

60

0

1

0

2100

0

Oil Rate mbd

WI Rate mbd

GI Rate mmscfdGOR scf/stb

Ula Historical ProfilesOverview Field History Future WAG SummaryCurrent WAG

Requirements to build the Ula WAG

• Appropriate water handling capacity upgraded in 1992 and 1994

• Reservoir pressure above minimum miscibility pressure (~5000 psi / 345 bar)

• Appropriate gas handling capacity 60 mmscfd gas processing (1.7 mill Sm3)

• Gas compression installed in 1993-1994 for gas lift

• Gas supply Re-inject gas after export route via Cod Field lost, Tambar tie-in

• Conversion of water injectors to gas (and water) injectors

0

50000

100000

150000

200000

250000

Oct

-86

Oct

-88

Oct

-90

Oct

-92

Oct

-94

Oct

-96

Oct

-98

Oct

-00

Oct

-02

Oct

-04

Oct

-06

Oct

-08

Pro

duct

ion &

inje

ctio

n

0

1000

2000

3000

4000

5000

6000

7000

8000

Res

ervo

ir P

ress

ure

Injected Water, bpd

Produced Water, bpd

Reservoir Pressure, psi


Current WAG Scheme

• 3 vertical WAG producers up-dip

• 4 vertical WAG injectors down-dip

− 1st injector (A03A) converted in 1997

− 3 additional injectors in 2001/ 2002 following Tambar tie-in

− New WAG injector behind WAG flood front (A09A) in 2006

• Current injection capacity

− 53 mmscf/d gas (1.5 mill Sm3)

− 70,000 bbl/d water (11000 Sm3)

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

A15

A18

A12A

A11

A03AA09A

A13A

A04

A07C

Ula Top Structure Map


Ula WAG Sectors

• Large sectors (1km – 2.5 km)

• Sectors identified through tracer programme

− Originally with water tracers (waterflood sectors)

− Verified with gas tracers (WAG sectors)

• Initial breakthrough times

− Water: 11 to 55 months

− Gas: 15 to 35 months


A-11

81/12/1515/37/88/23

50/22/2020/28/88/84/84

<8/30/3555

36

23

35

35/140/39/3131/40/40

73

27

66/140

11

54/22

3131/40/42

Waterflood sectors

WAG sectors

50/22

Tracer travel time, months

0

2

4

6

8

10

19

96

19

98

20

00

20

02

20

04

20

06

Oil rate (mbd)

0

2

4

6

8

10

19

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98

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00

20

02

20

04

20

06

Oil rate (mbd)

0

2

4

6

8

10

19

96

19

98

20

00

20

02

20

04

20

06

Oil rate (mbd)

N

A18

A15

A12A

(~1600 m3/d)

WAG Works in Ula

• Historically 5-10 mbd of WAG oil (800-1600 Sm3/d)

− 25-50% of Ula production

• Total WAG oil: ~15 mmstb (2.2 mill Sm3)

• Current scheme will recover over 3% of STOOIP


10

20

30

40

50

60

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

Gas

Inje

ctio

n, m

msc

fd

A13A: 35 bcf

A09A: 10 bcf

A07C: 31 bcf

A04: 11 bcf

A03A: 24 bcf

Ula Gas Injection

• 110 bscf of injected gas (3.1 bill Sm3)

− ~20% recycled gas

• WAG oil produced from all 4 sectors

− Indicated by gas tracer data and confirmed by well test results

• Limited sweep in lower perm Unit 3

− Verified by PLTs in injectors while on gas and water injection


WAG Surveillance

Key to Evaluating Benefits of WAG

• Gas tracer injection and sampling

• PLT in injectors

• Weekly WC measurements

• Monthly well tests

• Continuous THP monitoring

• Injectivity

• WAG slug identification

• A09A core in mature WAG sector

• 4D seismic being evaluated

A03A PLT

3 injection

zones

W-12 (A12A)

60

65

70

75

80

85

90

95

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n.0

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n.0

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06

Date

wat

ercu

t (v

ol%

)

watercut

A12A WC


Data acquisition behind WAG flood front

Extensive Data Acquisition Program in 2006

• A09A was drilled in a mature WAG sector

• Reservoir was cored & logged

− To evaluate effectiveness of current WAG scheme

− To quantify Sor distribution

• 101 meters of core (100% core recovery)

• Performed extensive study program

− Over 800 core plugs taken for analysis

− Routine core & fluid sample analysis

− Sw and GC, (well site and lab plugs)

− SCAL m & n, Rw from w/s plugs

− Log AnalysisCurrentWAG

Injector

ExistingWAG

Producer

Sorm from core

Sorw from core

A9A

A15

A3A

CurrentWAG

Injector

ExistingWAG

Producer

Sorm from core

Sorw from core

A9A

A15

A3A

30cm20cm 20cm15cm 15cm30cm20cm 20cm15cm 15cm


WAG Injector

Water injector

Unit 1 Producer

WAG Producer

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

A15

A18

A12A

A13A

A03AA09A

A04

A07C

A11

• Revealed 2 WAG tongues related to injection of gas in A03A• Consistent message from different data sources• Sorm and Sorw in line with previous SCAL data

Tongue 1Sorm~5-15%Sg~10-40%

Tongue 2Sorm~5-15%Sg~10-50%

G

G

FluidSamples

GR, PORGR, POR Kh, KvKh, Kv T, RwT, Rw So, SwSo, Sw NMR: SgNMR: Sg PNC: SgPNC: SgRCI: PRCI: P

Cn/C40Cn/C40

A09A WAG Observation OverviewOverview Field History Future WAG SummaryCurrent WAG

Moving to Expanded WAG (XWAG)

• Successful current WAG scheme in Ula

− Clear indication of mobilized oil production

− ~ 15 mmstb incremental oil produced

• Extensive data acquisition in A09A to evaluate effectiveness of WAG

− Clear indication of reduction of Sorm 10%

A02B

A01B

A14A

A10A A05B

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

A18

A12A

A13A

A03AA09A

A04

A07C

A11

A15

Current WAG


A02B

A01B

A14A

A10A

A05B

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

A15

A18

A12A

A13A

A03AA09A

A04

A07C

A11

WAG14

WAG16

WAG8

WAG13

WAG1

WAG15

WAG18

Expanded WAG

• Extensive simulation studies on Expanded WAG

− Indicate potential for a healthy additional incremental recovery

− Maximize recovery with Unit 3 horizontal injectors

XWAG Screening

A-13A

A-3A

A-4

A-7C

A-10A

A-12A

A-14A

A-15

A-17A

A-18

A-1B

7/12-2

7/12-3

7/12-3A

7/12-4

7/12-6

7/12-7

7/12-8

7/12-9

A-1

A-10

A-12

A-13

A-14

A-16

A-16A

A-17

A-1A

A-2A

A-3

A-5

A-5A

A-7

A-7B

A-8

A-8AA-9

A-11

Legend

Oil Producer

Water Injector

WAG Injector

Suspended or Abandoned

Well trajectory

-3828 m ssl FWL

-3756 m ssl FWL

-3714 m ssl FWL

-3528 m ssl FWL

-3557 m ssl FWL

X-WAG Horisontal Injector

WAG 1

WAG 2

WAG 3

WAG 4

WAG 5

WAG 6

WAG 7

WAG 8

WAG 9

WAG 10

WAG 11

WAG 12

Possible pre-Producers.

WAG 13

WAG 14

WAG 15

WAG 16

WAG 17

WAG 18

Reserves by 2020 for single well cases, constant gas injection of 60 mmscfd

A-13A

A-3A

A-4

A-7C

A-10A

A-12A

A-14A

A-15

A-17A

A-18

A-1B

7/12-2

7/12-3

7/12-3A

7/12-4

7/12-6

7/12-7

7/12-8

7/12-9

A-1

A-10

A-12

A-13

A-14

A-16

A-16A

A-17

A-1A

A-2A

A-3

A-5

A-5A

A-7

A-7B

A-8

A-8AA-9

A-11

Legend

Oil Producer

Water Injector

WAG Injector

Suspended or Abandoned

Well trajectory

-3828 m ssl FWL

-3756 m ssl FWL

-3714 m ssl FWL

-3528 m ssl FWL

-3557 m ssl FWL

X-WAG Horisontal Injector

WAG 1

WAG 2

WAG 3

WAG 4

WAG 5

WAG 6

WAG 7

WAG 8

WAG 9

WAG 10

WAG 11

WAG 12

Possible pre-Producers.

WAG 13

WAG 14

WAG 15

WAG 16

WAG 17

WAG 18

Reserves by 2020 for single well cases, constant gas injection of 60 mmscfd

2 XWAG targets chosen for recoverable resources, location, drillability from existing slots, & good geologic understanding

A02B

A01B

A14A

A10A

A05B

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

A15

A18

A12A

A13A

A03AA09A

A04

A07C

A11

Ula top structure map

WAG14

WAG16

7 XWAG targets chosen for recoverable resources, and location (sweep)

A02B

A01B

A14A

A10A

A05B

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

A15

A18

A12A

A13A

A03AA09A

A04

A07C

A11

WAG14

WAG16

WAG8

WAG13

WAG1

WAG15

WAG18

25 XWAG targets screened and ranked according to recoverable resources


XWAG Enablers

• 2006: A09A WAG injector drilled & cored behind flood front (10% Sorm)

• 2007-2008: Increase gas handling capacity with Ula Gas Upgrade (UGU)

− Gas handling 60 mmscfd 120 mmscfd (3.4 mill Sm3/d)

• 2007: Identify locations & slots for 2 new WAG injectors

• 2007-2008: Investigate passive downhole flow control for uniform injection in horizontal wells

• 2008-2010: Replace water injection pumps 140,000 bbls/d (22k Sm3/d)

• 2008: Commitment to purchase Oselvar gas volumes from 2011Blane

Tambar MPP

Tambar East

Tambar Base

Oselvar

Future gas for Ula WAG

Scheme: >150 bcf


XWAG Plans

A02B

A01B

A14A

A10A

A05B

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

A15

A18

A12A

A13A

A03AA09A

A04

A07C

A11

WAG14

WAG16

WAG8

WAG13

WAG1

WAG15

WAG18

WAG14

WAG16


20

13

-20

17 • Potential for 5 more horizontal

injectors

− Install new wellhead platform

− Continue injection in Unit 3 with long, horizontal wells

20

17

+

• Evaluate additional sources of gas for long term

• Full project has potential to increase recovery by ~10% of STOOIP

− Bring total recovery to ~70% through technology

• Enable Ula to produce past 2028

20

09

-20

12

• Plans for 2 new horizontal injectors in Unit 3 (WAG14 in 2009 & WAG16 in 2012)

− Target deeper injection in Unit 3

− Long, horizontal injectors ~1000m with passive downhole flow control for uniform injection

XWAG Challenges and Mitigations

• Commerciality - high early investment and late pay-back

− Project phasing

− 3rd Party tie-ins (Oselvar)

• Completion conformance

− Passive downhole flow control

− Evaluation of concept needed

• Reservoir response prediction

− Comprehensive uncertainty analysis to understand range of outcome

• Life of field surveillance plan

− Surveillance commitment


A02B

A01B

A14A

A10A

A05B

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

WAG Injector

Water injector

Unit 1 Producer

WAG Producer

A15

A18

A12A

A13A

A03AA09A

A04

A07C

A11

WAG14

WAG16

WAG8

WAG13

WAG1

WAG15

WAG18

Summary

• Ula forms a strategic hub in the Norwegian North Sea

− Successful tie-ins of Tambar, Blane, and potentially Oselvar

• Miscible WAG is an effective process in Ula

− Clear indication of mobilized oil production from WAG producers

− Clear indication of reduced Sor (down to 10%) in WAG flooded zone from A09A core/log data

− Recovery increased and lifetime extended

• WAG Expansion will realize a healthy additional incremental recovery of ~10% STOOIP

− Enables production at current levels beyond license period of 2028

020406080

100120140

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140

0Oil

Rat

e m

bd

arrested decline

0.00.40.71.11.41.82.1

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GI/WAGWI


Questions?

Acknowledgements:Thanks to BP Norge AS and DONG E&P Norge AS for allowing this information to be shared.Thanks to Masoud Haajizadeh, Simon Thomas, Kevin Best, & Stijn de Jongh for contributions to slide material.

Documents

Building & Expanding the Ula WAG