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Annual reservoir development plan Norne Field

2004

Title:

Annual reservoir development plan Norne Field

2004

Document no.: Contract no./project no.: Filing no.:

Classification: Distribution:

Open Open

Distribution date: Rev. date: Rev. no.: Copy no.:

2004-09-02

Author(s)/Source(s):

Odd-Willy Lind

Subjects:

Reservoir management, production profiles, IOR plan

Remarks:

Valid from: Updated:

01.01.2004

Responsible publisher: Authority to approve deviations:

HNO Norne PETEK

Techn. responsible: Name: Date/Signature:

Odd-Willy Lind

Responsible: Name: Date/Signature:

HNO Norne PETEK Odd-Willy Lind Martin Springer

Recommended: Name: Date/Signature:

HNO Norne PETEK Ole Magnar Drønen

Approved: Name: Date/Signature:

HNO Norne LED Annefi Markman

Doc. no. Date Rev. no.

Annual reservoir development plan Norne Field 2004

2004-09-02

Table of contents 1 Introduction........................................................................................................................................... 4 1.1 Summary and general field information ................................................................................................. 4 1.1.1 General field information........................................................................................................................ 4 1.1.2 Resources and recoverable reserves........................................................................................................ 7 1.1.3 Drainage strategy and well plans ............................................................................................................ 8 2 Time lapse seismic-4D reservoir monitoring .................................................................................... 10 3 Annual well plan 2004......................................................................................................................... 13 3.1 Drilling plan 2004 ................................................................................................................................. 13 3.2 Well work over plan 2004..................................................................................................................... 14 3.3 Data acquisition plan 2004.................................................................................................................... 15 4 Norne Field production plan 2004 ..................................................................................................... 16 4.1 Production and injection volumes......................................................................................................... 16 4.1.1 Oil production ....................................................................................................................................... 17 4.1.2 Factors that limit the oil production ...................................................................................................... 17 4.1.3 Gas disposal volumes............................................................................................................................ 17 4.1.4 Process and transport capacity .............................................................................................................. 18 5 Improved recovery activities.............................................................................................................. 19 5.1 Tofte drainage ....................................................................................................................................... 19 5.2 Ile drainage............................................................................................................................................ 19 5.3 Garn drainage........................................................................................................................................ 19 5.4 Field studies .......................................................................................................................................... 19 5.5 Well chemicals and sand erosion ...........................................................Error! Bookmark not defined. 5.6 Well studies and zone control ............................................................................................................... 20 6 Updated long term production profiles and recoverable reserves.................................................. 21 7 HSE considerations ............................................................................................................................. 23 7.1 Safety .................................................................................................................................................... 23 7.2 Environment.......................................................................................................................................... 23

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C:\Documents and Settings\dadashpour\Local Settings\Temporary Internet Files\Content.IE5\SRXB2IBT\Annual reservoir development plan 2004.doc

1 Introduction

This document is an annual update of the “Reservoir management plan – Norne Field” from 2001 (ELARK 01A05*183).

1.1 Summary and general field information

1.1.1 General field information

The Norne Field is situated in the blocks 6608/10 and 6508/1 in the southern part of the Nordland II area in the Norwegian Sea. Its location, relative to the nearby fields is shown in Figure 1.1.

Figure 1.1 The location of the Norne Field

TRONDHEIM

68 °

67 °

66 °

65 °

64 °

2° 4° 6° 8° 10° 12° 14° 16°

HEIDRUNSMØRBUKK

MIDGARD

DRAUGEN

NJORD

85

km

HARSTAD

SANDNESSJØEN

BRØNNØYSUND

STJØRDAL

BODØ

Tjeldbergodden

SMØRBUKK SØR

KRISTIANSUND

69°

Haltenpipe

200 kmNORNE

Norne

Svale

Stær

Norne G-Segment

Falk

Heidrun

Skarv

Norne

Svale

Stær

Norne G-Segment

Falk

Heidrun

Skarv



2004-09-02


The Norne Field consists of two separate oil compartments, the Norne Main Structure (Norne C-, D and E-Segment) and the Northeast Segment (Norne G-Segment) (Figure 1.2). The Norne Main Structure was discovered in December 1991 and includes 97% of the oil in place. The discovery well, 6608/10-2, proved a total hydrocarbon-bearing column of 135 m in the rocks of Lower and Middle Jurassic age. The column consisted of a 110 m thick oil leg with an overlying gas cap. Well 6608/10-3 confirmed the results of the discovery well.

7327167

7325167

7323167

7321167

7319167463313461313459313457313455313

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42

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62

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0 0

2 7 0 0

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7 00

2 7 0 0

2 7

2 52

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0572

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75

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00

28

25

28

50

28

75

29

00

2

90 0

29

25

29

2 5

29 5

0

579

2

000

3

30

25

52

03

30

50

30

75

310

0

31

253

15 0

31

75

3 20 0

KILOMETERS

0 1 2

10-2

10-3

10-4

B-2

B-4

C-1

D-1

D-2

D-4

E-3

C-2

F-1

B-3

E-1

B-1

C-3

F-2

E-2

F-3

D-3 A

E-4 A

E-3 A

B-4 B

F-4

455313 457313 459313 461313 463313

P17

Sisik

Trost

Stær

P20

D-4 A

D-1C

10-8

C-4 A

P24

P19 P25

P18

P22P27P28

P34

C-4

P36

P26

P32

P33

P31

P35

P30

B-4D

C

D

GE

7327167

7325167

7323167

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7319167

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7327167

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42

57

42

00

52

2 5

2 5

25 2 5

2 52 5

52

52

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52

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2

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2 5 7 5

57

52

2

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2 6 0 0

00

62

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5

26 2

5

2 6 5 0

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2

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30

50

30

75

310

0

31

253

15 0

31

75

3 20 0

KILOMETERS

0 1 2

KILOMETERS

0 1 2

10-2

10-3

10-4

B-2

B-4

C-1

D-1

D-2

D-4

E-3

C-2

F-1

B-3

E-1

B-1

C-3

F-2

E-2

F-3

D-3 A

E-4 A

E-3 A

B-4 B

F-4

455313 457313 459313 461313 463313

P17

Sisik

Trost

Stær

P20

D-4 A

D-1C

10-8

C-4 A

P24

P19 P25

P18

P22P27P28

P34

C-4

P36

P26

P32

P33

P31

P35

P30

B-4D

C

D

GE

Figure 1.2 The Norne Field segments and wells

The Norne Main Structure is relative flat with generally a gas filled Garn Formation and the gas oil contact in the vicinity of the Not Formation clay stone. The northern flank dips towards north-northwest with an oil leg in the Garn Formation (Figure 1.3). Gas-oil (GOC) and oil-water (OWC) contacts in the different formations and segments are listed in the table below.

Formation C-segment D-segment E-segment G-segment OWC GOC OWC GOC OWC GOC OWC GOC Garn 2692 2582 2692 2582 2618 2582 2585 No gas cap

Ile 2693 2585 2693 2585 2693 2585 Water filled Water filled

Tofte 2693 2585 2693 2585 2693 2585 Water filled Water filled

Tilje 2693 2585 2693 2585 2693 2585 Water filled Water filled

Acquired reservoir pressure data from the development wells indicate that the Not Formation is sealing and there is no reservoir communication across the Not Formation during production.



2004-09-02


Ca

200m

OilGas

SW NE

F-3H

GOC=2575m

C-2H

C-4HB-1H

B-3HE-2H

E-3AH

Tilje Fm.

Tofte Fm.

Not Fm.

Garn Fm.

L.Ile Fm.

OWC=2693m

GOC=2580m

OWC=2618m

Ca 7 km.

U.Ile Fm.

D-1CH

Ca

200m

OilGas OilGas

SW NE

F-3H

GOC=2575m

C-2H

C-4HB-1H

B-3HE-2H

E-3AH

Tilje Fm.

Tofte Fm.

Not Fm.

Garn Fm.

L.Ile Fm.

OWC=2693m

GOC=2580m

OWC=2618m

Ca 7 km.

U.Ile Fm.

D-1CH

Figure 1.3 NE-SW running structural cross section through the Norne Field with initial fluid contacts and

current drainage strategy.

The field is being developed with five templates at the sea bottom connected to a floating production vessel (Figure 1.4). Development drilling started in August 1996, and the oil production started the 6th November 1997.

Figure 1.4 The development of the Norne Field and the satellites Stær and Svale.



2004-09-02


In September 2004 the Norne Field is producing oil from all 12 well slots. 8 injectors have been drilled, and water is injected in 7 wells and gas in one well. 60 mill Sm³ oil has been produced since the production started, which is approximately 40% of the oil in place or 65% of recoverable reserves. Gas export from the Norne Field was started in 2001 (Figure 1.5). Approximately 1 GSm³ of gas is exported every year.

Figure 1.5 Norne and Heidrun gas export pipe through the Åsgard Transport Approximately 90% of the Norne Field area is within the PL 128 licence block 6608/10, and the rest of the field lies within the north-western part of the block 6508/1; PL 128B. The participating interests in the Norne Field and PL128 are:

Norne PL128 Statoil ASA (operator) 25% 40.4545% SDFI/Petoro as 54% 24.5455% Norsk Hydro Prod. a.s. 8.1% 13.5% ENI Norge AS 6.9% 11.5% Shell (Enterprise) 6% 10%

The Norwegian authority approved the PDO for the Norne satellites Svale and Stær in June 2004, and work has been initiated to start the oil production from the satellites in October 2005. Most likely recoverable reserves estimated for the Norne satellites Svale and Stær is 10.4 mill Sm³ oil.

1.1.2 Resources and recoverable reserves

The most likely in-place volumes and official recoverable reserves for the Norne Field are:



2004-09-02


PDO Official RNB 2004

Oil in place, STOIIP x 106 Sm3

164.2 157.0

Gas in place (free & solution)

x 109 Sm3

29,9 29.8

Recoverable oil reserves x 106 Sm3

72,4 87.4

Recoverable gas reserves x 109 Sm3

- 13.65

Approximately 80% of the oil reserves on the Norne Main Structure is located in the Ile and Tofte Formations. The free gas is primarily located in the Garn Formation.

1.1.3 Drainage strategy and well plans

The main goal is to develop the Norne Field such that the economic optimum production profile is obtained. In the first year of production the reservoir management focus was on utilising the processing and production potential at their maximum. Today the focus is on optimising the value creation in the license PL128 by: • Safe and cost effective drainage of proven reserves • Prove new reserves at optimal timing to utilise existing infrastructure and exploring the

potential in the license • Adjust capacities in cases where this could be done cost effectively • Produce at least 7.68 mill Sm³ oil in 2004 • Improve drainage strategy with low cost infill wells as multilateral/MLT and through

tubing drilled wells/TTRD • Improved description and optimised drainage strategy to achieve recoverable reserves to

more than 90 mill Sm³. • Increase reservoir pressure in Ile Formation at the Norne C-Segment. The Norne Field is now developed only with horizontal producers. However, to accelerate the build-up of well potential until plateau production was reached, some of the first producers were drilled vertical to some deviated. All these wells have been sidetracked to horizontal producers. The pre-start drainage strategy was to maintain the reservoir pressure by re-injection of produced gas into the gas cap and water injection into the water zone. However, during the first year of production it was experienced that the Not shale is sealing over the Norne Main



2004-09-02


Structure, and the gas injection has been changed to inject in the water zone and the lower part of the oil zone (Figure 1.6). The horizontal oil producers in Tofte and Lower Ile Formation will be plugged and sidetracked (MLT and TTRD) and drilled horizontal in Upper Ile Formation just below the Not Formation shale when the water cut becomes to high (>70-80%) resulting in problems to lift the liquid.

1997 1998 2003 2005 2008

Tofte Fm.

Garn Fm.

L.Ile Fm.

U.Ile Fm.

1997 1998 2003 2005 2008

Tofte Fm.

Garn Fm.

L.Ile Fm.

U.Ile Fm.

Figure 1.6 The drainage strategy for the Norne Field from pre-start and until 2008.



2004-09-02


2 Time lapse seismic-4D reservoir monitoring

Norne has in the last years been very active using time lapse seismic in reservoir monitoring. The base survey ST9203 was acquired in 1992 well before oil production started in 1997. The first acquisition survey for time lapse monitoring was performed in 2001, and then repeated in 2003 and 2004 (Figure 2.1).

Norne 2003 ST0305

Norne 2004ST0409

Svale

Stær

6.9 km

7.9 km

18.4 km

12.4 km

146 km2

85 km2 Norne 2003 ST0305

Norne 2004ST0409

Svale

Stær

6.9 km

7.9 km

18.4 km

12.4 km

146 km2

85 km2

Figure 2.1 Seismic surveys in the Norne Field area



2004-09-02


The Norne Field is a flat horst structure and a change in fluid contacts during production has to be monitored by the difference in seismic signals from the reservoir zone from year to year. In this context it is very important for repeatability that the seismic lines are acquired at the same geographical position each time and the seismic acquisition parameters are identical to the previous surveys. For the 4D surveys on the Norne Field, WesternGeco Q-marine active streamer steering have been used, allowing accurate positioning of streamers for reliable repeat surveys. Survey Year

acquisition Purpose Acquisition

technology Acquisition

area Number

of sources

Number of

streamers

Streamer separation

ST9203 1992 Exploration 3D

Conventional Norne-PL128 and PL159

2 3 100 m

ST0113 2001 Time lapse monitoring

4D

Q-marine Norne Field 42 km²

1 6 50 m

ST0103 2001 Exploration 3D

Q-marine Norne, Svale and Stær 310 km²

2 6 100 m


4D

Q-marine Norne Field 85 km²

1 6 50 m


4D

Q-marine Norne, Svale and Stær 146 km²

1 6 50 m

ST0411 2004 Exploaration 3D

Q-marine Linerle + 2 6 100 m

Results from the 4D seismic have been important in detecting fluid movement for reservoir management and production. A planned well path for horizontal production well (D-1 CH) has been successful changed based on results from time lapse monitoring ST0113-ST0305. In the targeting remaining oil process (TRO) use of 4D seismic data is an important tool (Figure 2.2-2.4) • OWC from 4D 2003; indicates variation over the field• OWC from 4D 2003; indicates variation over the field

Figure 2.2 The Norne Field seen from south with the oil-water contact interpreted from 4D data 2003



2004-09-02


Figure 2.3 The Norne Field seen from NE. The structural depth map is at top Tofte level and blue coloured area is where top Tofte is above OWC 2003.

E-2H - Existing well

Planned well TTRD

D-3AH - Existing well

Planned wells ML

Top Tilje + OWC 2003

E-2H - Existing well

Planned well TTRD

D-3AH - Existing well

Planned wells ML

Top Tilje + OWC 2003

Figure 2.4 Northern part of Norne C-Segment with production well D-3 AH, D-Segment and E-Segment with production well E-2 H (seen from east).



2004-09-02


3 Annual well plan 2004

3.1 Drilling plan 2004

The drilling plan comprises drilling from sub-sea template by use of rig. The following table and Figure 3.1 summaries the planned drilling activity (CAPEX):

Well Reservoir Type/segment Production/injection start

Cost mill NOK

Comment

B-4 DH Upper Ile Oil producer/ C-segment July 2004 199

Drill first a pilot hole B-4 CH to confirm

GOC and OWC

D-3 BY1H and D-3 BY2H

Upper Ile Oil producer/ C and D-segment September 2004 238+ 32

Multilateral well,

depending on higher WCT in

D-3 AH,

E-2 AH Upper Ile Oil producer/ E-segment October 2004 84+10

Through tubing drilling

(TTRD), depending on

higher WCT in E-2 H

B-3 AH Upper Tofte Oil producer/ C-segment October 2004 2

planning TTRD from B-

3 H

Sum drilling 565



2004-09-02


Well production

Zone

E-4AHE-3AH

E-2H

E-1H

D-4AH

D-3AHD-2H

D-1CH

B-4BH

B-3HB-2HB-1H

Well

NE segment – single drainage point

Garn E-segm. – single drainage point thin oil leg30

34

Plug – perf. Planned 200438

No intervention planned0

ML sidetrack planned 200448

No intervention planned1

Sidetracked. Set in production Nov. 03

Unsuccessful intervention due to scale

TTRD Planned 2005 (only C-segm. illustr.) 18

No interventions planned0

CommentWCT

Tofte

Lower Ile

Upper Ile

Garn

ZoneWell

30

0No intervention planned

Unsuccessful intervention due to scale

Intervention Sept. 030

CommentWCT

3000 6000

Oil production rate

TTRD planned for 2004

2003 new well potential: 9000 Sm3/sD

Planned 2004

Untouchable

Mulighet ut over budsjett

X-XX

Figure 3.1 Drilling and well work over plan Norne Field 2004

3.2 Well work over plan 2004

The well work over plan is a summary of activities that are likely to be performed in 2004 within the approved budget in order to maintain well production potential. It is likely that further activities will have to be carried out in order to maintain well potential. The amount and cost of these activities is however uncertain. The activities which are listed below have an estimated cost within the approve budget of …. mill NOK including the data acquisition activities listed in section 3.3. The individual activities will be subject to cost/benefit analysis for each operation.

Activity Activity/wells Number of operations

Individual cost mill NOK

SUM cost mill NOK

Scale squeeze 1 5 5 (OPEX) Plug and perf E-1 H 59 59 (CAPEX)



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3.3 Data acquisition plan 2004

The estimated level of data acquisition and analysis from production/injection wells is given in the table below. The data acquisition strategy for open hole logging and coring in new wells remains unchanged.

Activity Number of operations

Singel cost mill NOK

SUM cost mill NOK

4D seismic acquisition and processing 1 38 38

Production and saturation logging 1 38 38 (OPEX)

Ion/tracer/PVT-analysis



2004-09-02


4 Norne Field production plan 2004

4.1 Production and injection volumes

The total oil production volume in the table (7.60 mill Sm³) is not consistent with the Production Permit for 2004, which is 7.68 mill Sm³. Based on delay in drilling new drainage sidetracks, the well potential was reduced compared to the prognosis. The prognosis for the total oil production for 2004 has been revised to 7.3 mill Sm³.

Days in month 2004 Application

Sm³ Cum.

ApplicationSm³

ProducedSm³

Prod. Application

pr. Day Sm³

Produced pr. day

Sm³

Cum prod. Sm³

Prog. PUF (%) PUF (%)

31 Jan 819 041 819 041 719 344 26 421 23 205 719 344 95 95.73 29 Feb 736 156 1 555 197 609 548 25 385 21 019 1 328 892 95 96.26 31 March 756 070 2 311 266 640 823 24 389 20 672 1 969 715 95 98.43 30 April 702 991 3 014 257 571 279 23 433 19 043 2 540 994 95 90.01 31 May 697 940 3 712 198 599 567 22 514 19 341 3 140 561 95 94.63 30 June 648 942 4 361 140 612 307 21 631 20 410 3 752 868 95 98.49 31 July 644 280 5 005 420 645 239 20 783 20 814 4 398 107 95 95.48 31 Aug 499 208 5 504 628 420 492 16 103 13 564 4 818 599 95 30 Sept 460 448 5 965 076 15 348 4 818 599 95 31 Oct 571 425 6 536 501 18 433 4 818 599 95 30 Nov 531 309 7 067 810 17 710 4 818 599 95 31 Dec 527 492 7 595 302 17 016 4 818 599 95

4 818 599

05

1015202530

Jan

FebMarc

hApri

lMay

June Ju

lyAug Sep

tOct

Nov Dec

Prod

uctio

n ra

te p

r. da

y (1

000

Sm3/

D)

024681012

Cum

ulat

ive

prod

uctio

n (m

ill. S

m3)

Cum. application Prod. application pr. dayProduced pr. day Cum prod.



2004-09-02


January February March April May June July August September October NovemberDecemberApplication 819 041 1 555 197 2 311 266 3 014 257 3 712 198 4 361 140 5 005 420 5 504 628 5 965 076 6 536 501 7 067 810 7 595 302Rev. Prog. 719 344 1 328 892 1 969 715 2 578 409 3 200 857 3 796 910 4 406 306 4 887 044 5 331 993 5 974 511 6 628 987 7 320 779Production 719 344 1 328 892 1 969 715 2 540 994 3 140 561 3 752 868 4 398 107 PUF (%) 95.73 96.26 98.43 90.01 94.63 98.50 95.48 GasExport 140.51 103.86 115.13 96.45 89.35 61.42 76.79

4.1.1 Oil production

The oil production estimate is based on the following: mill Sm³

• Production potential (well potential) 100% xx o Well work over - xx o Planned maintenance -xx o Norne PSV revision stop in September -xx

• Non-planned reduced production - xx

• Expected oil production 7.60 • Oil production target 7.68 • The expected PUF (Process utility factor) 2004 95%

4.1.2 Factors that limit the oil production

The following main factors limit the oil production of the Norne Field:

1. Sand production in some wells 2. Limited pressure support in Tofte/Ile reservoir in the C-segment 3. Limited pressure support in the Garn reservoir in the D- and G segment

4.1.3 Gas disposal volumes

The gas handling capacity is 7.0 mill Sm³/d. The gas export rate to Åsgard Transport is based on the allocated volume 1.0 G Sm³ for contract year 2003 (01.10.03-01.10.04). The table below indicates the daily export rate to fulfill the delivery.



2004-09-02


The surplus is injected into the reservoir to maintain the reservoir pressure. The injection gas will be distributed within the Norne C-segment by using the well C-3 H as the gas injector for part of the year and the rest of the year in C-1 H.

4.1.4 Process and transport capacity

The current maximal production rate for the installation is a total mass stream equal to the combination of 45,000 Sm³/d liquid and 7.0 mill Sm³ gas. Process capacities Norne ship Total liquid production 45,000 Sm³/d Produced water treatment 20,000 m³/d Water injection 53,000 m³/d Gas 7 mill Sm³/d Gas injection 7 mill Sm³/d

Daily export rates given in rich gas from Norne Regularity assumption: 97 %

PermissionMonth Cumulative Daily rate Cumulative Comment Daily rate Cumulative Comment Daily rate Cumulative Comment

mill Sm3mill

Sm3/cD mill Sm3mill

Sm3/cD mill Sm3mill

Sm3/cD mill Sm3Okt 31 2.30 71 2.0 60 2.30 71Nov 30 2.56 148 2.5 133 2.56 148Des 31 3.36 252 2.5 208 3.36 252Jan 31 4.53 393 3.5 313 4.53 393Feb 29 3.58 496 3.5 412 3.58 496Mar 31 3.71 612 3.5 517 3.71 612Apr 30 3.22 708 3.42 617 3.22 708Mai 31 2.88 797 3.42 719 3.42 811Jun 30 2.05 859 3.42 819 2.15 873Jul 31 3.42 922 3.15 968Aug 31 3.42 971 16 days stop 3.15 1014 16 days stopSep 30 1140 3.42 1048 7 days stop 3.15 1084 7 days stop

Sales gas (40 MJ) 1000 919

Norne Gas Export Planning

Actual export Lates approved gas export program Proposed revised program



2004-09-02


5 Improved recovery activities

5.1 Tofte drainage

5.2 Ile drainage

To improve the oil recovery in Upper Ile reservoir work will be done to better the understanding of this reservoir, as carbonate cemented layers and reservoir communication before drilling more low cost drainage locations as horizontal wells (MLT and TTRD) at the uppermost part of the Upper Ile Formation.

5.3 Garn drainage

5.4 Field studies

The main objective will be to provide updated geological models and simulation models, which will be the basis for overall drainage strategy for the Tofte-Ile and Garn reservoirs. In 2004 a new full-field 2D geological model (Norne deterministic geomodel 2004) and a 3D geological model (Norne stochastic geomodel 2004) will be finalized. A simulation model based on the Norne deterministic geomodel 2004 will also be finalized. 4D seismic monitoring (Section 2) and evaluation of the data will be performed and implemented in the targeting remaining oil (TRO) process, which will be done in 2004.

5.5 Sand and scale

As a consequence of water production there is a risk for scale deposit in both the subsurface and surface equipment. Besides the reduction in well productivity due to restrictions in the well stream these deposits can lead to failure of valves such as the down hole safety valve and hence pose a severe safety problem. Understanding the mechanisms for scale deposits at the Norne field will therefore be of vital importance in finding a strategy for efficient treatment of scale deposits. Like scale deposit is also sand production closely connected to water production. This sand production has little effect on the well productivity. However, sand production will lead to erosion in the production system. To avoid intolerable erosion due to sand production the



2004-09-02


production from sand producing wells has to be choked back to both reduce the amount of sand produced and the flow velocity. Again, excessively sand production poses a severe safety problem in addition to the obvious economically consequences due to reduced production.

5.6 Sub sea improved oil recovery (SIOR)

SIOR volumes Norne 2004 Activities Amount Unrisked MSm³ Risked MSm³ Total unrisk MSm³ Total ris

Low cost drainage 9.3

Through tubing drilling/MLT 10x0.5 6.0 5.00

e-drilling 0.8 0.27

New drilling concepts incl. Monobore drilling 2.5 1.00

Sand management 1.00

Low cost intervention 5.5

LWI - wire line 0.6 0.60

LWI - coiled tubing 0.9 0.40

Retrofit DIACS system/chemical 4.0 1.00

Reduce wellhead pressure 1.0

Gaslift 1.0 0.23

Identify drainage points and intervention needs 2.0 4D/4C prediction of fluid and pressure distribution 1.0 2.00 Fast update of static models 0.5 0.25 Seismic derived saturation maps in history matching 0.5 0.25 Improved drainage strategy 1.50

Integrated production management 1.1 Improved data integration, methods and software 0.2 0.20 Software for "right time" reservoir management 0.1 0.35 Improved work processes 0.8 0.25

Total 18.9 1

5.7 Well studies and zone control



2004-09-02


6 Updated long term production profiles and recoverable reserves

The updated long-term production profile is presented in the table below. This profile has been updated in October 2003. The oil profile is based on simulation results combined with production experience from the last year. The ultimate oil recovery from the field until 2016 is estimated to 87.4 mill Sm³. The oil production profile is also shown in the table below and in the figure 6.1 with the estimated P90 and P10 profiles. The gas export profile is based on estimate of optimal gas export rate.

Year

Oil production

mill Sm³ NGL

mill tonn Gas export

GSm³

Water production

mill Sm³ 1997 0.42 0,000 0,000 0,020

1998 6.32 0,000 0,000 0,230

1999 8.31 0,000 0,000 0,095

2000 10.420 0,000 0,000 0,544

2001 11.300 0.108 1.030 0,430

2002 10.270 0.096 0.843 1.056

2003 8.600 0.122 0.932 1.762

2004 7.680 0.122 0.925 3.706

2005 5.351 0.122 0.925 7.334

2006 3.698 0.122 0.925 9.654

2007 3.080 0.122 0.925 10.023

2008 2.735 0.122 0.925 10.162

2009 2.268 0.122 0.925 10.142

2010 2.112 0.122 0.925 10.123

2011 1.601 0.122 0.925 10.115

2012 1.242 0.122 0.925 10.079

2013 0.798 0.122 0.925 10.086

2014 0.528 0.122 0.925 10.162

2015 0.457 0.076 0.578 10.162

2016 0.235 0.012 0.087 4.500

Total 87.425 1.756 13.645 120.385



2004-09-02


Year P10

mill Sm³ Basis

mill Sm³ P90

mill Sm³ 1997 0.42

1998 6.32

1999 8.31

2000 10.420

2001 11.300

2002 10.270

2003 8.600

2004 5.800 7.680 8.500

2005 4.200 5.351 7.800

2006 2.600 3.698 4.600

2007 2.000 3.080 3.800

2008 1.700 2.735 3.200

2009 1.300 2.268 2.700

2010 0.850 2.112 2.400

2011 0.500 1.601 2.000

2012 0.250 1.242 1.650

2013 0.100 0.798 1.300

2014 0.020 0.528 1.100

2015 0.000 0.457 0.900

2016 0.000 0.235 0.700

2017 0.000 0.000 0.620

2018 0.000 0.000 0.538

2019 0.000 0.000 0.528

2020 0.000 0.000 0.518

Total 75.0 87.4 98.5



2004-09-02


7 HSE considerations

7.1 Safety

The challenge related to safety at the installation in 2004 will be the increased activity associated with:

• Revision and maintenance in September • Scale treatment • Sand production

The main focus will be training involved personnel and direct participation in the projects from dedicated Statoil personnel.

7.2 Environment

The challenge related to environmental issues in 2004 is summarized below:

• In order to increase the water injection it is planned to add flow improver to the injection water. This chemical contains red components. Efforts will therefore be undertaken to replace this chemical with a more environmentally friendly substitute.

• Add a few words on produced water quality and discharge to the sea.

•



2004-09-02
