Cambodia, December 20041

Cambodia, December 2004

1

Production Curve Modeling

Dr. Alfred Kjemperud

Cambodia, December 20042

Cambodia, December 2004

2

Costs

Income

Time

Government

Phases and Lead Time

Pre-license Exploration Development Production AbandonmentProduction

Rehab.

Con

trac

t aw

ard

PDO

Lead Time

Cambodia, December 20043

Cambodia, December 2004

3

Production curve

Time

Volume

Build-up

Plateau

Decline

Cutoff

Lead TimeStart-up

Volume produced

on plateau

Plateau rate

Cambodia, December 20044

Cambodia, December 2004

4

Factors determining production

• No of wells• P/R ratio (%)

– Production on plateau/Reserve• Production rate per well• Plateau production rate• Remaining oil/gas at start decline• Decline rate (%)• Rate at Cut-off

Cambodia, December 20045

Cambodia, December 2004

5

P/R ratios• Large to Medium Fields: 5-10%• Small Fields: 15-20%

– Nkossa, Congo(440 mmbbl) 9%– Numbi, South, Angola (205) 10%– Zafiro, Eq. Guinea (105) 14%– Oombo, Angola (48)– Lubi, DRC (1) 30%– S. Asoma, Cameroon (1) 84%

Source: Wood Mackenzie

Cambodia, December 20046

Cambodia, December 2004

6

Oil ProductionOil Production

0.0

50.0

100.0

150.0

200.0

250.0

300.0

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

Year

Thou

sand

bbl

/yea

r

Oil [Thousand bbl/d]Assoc. Gas [Thousand o.e./d]

Cambodia, December 20047

Cambodia, December 2004

7

Gas ProductionGas Production

0.0

500.0

1000.0

1500.0

2000.0

2500.0

3000.0

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

Year

Gas

(Mill

ion

scf/d

ay)

Con

dens

ate

(Tho

usan

d bb

l/d)

Non Assoc. Gas [Million scf/d]Condensate [Thousand bbl/d

Cambodia, December 20048

Cambodia, December 2004

8

Statfjord Oil - NorwayOil Production - Statfjord, Norway560 million Sm3 (3520 Million bbl)

23 %

66 %

0

5

10

15

20

25

30

35

40

200220012000199919981997199619951994199319921991199019891988198719861985198419831982198119801979

Years

Mill

ion

Sm3

0 %

10 %

20 %

30 %

40 %

50 %

60 %

70 %

80 %

90 %

100 %

Oil Production

P/R percentage

P/R = 6.6

Cambodia, December 20049

Cambodia, December 2004

9

Oseberg Oil - NorwayOil Production - Oseberg Field, Norway

350 million Sm3 (2200 million bbl)

39.2 %

70.5 %

0

5

10

15

20

25

30

35

2001200019991998199719961995199419931992199119901989198819871986

Years

Mill

ion

Sm3

0.0 %

10.0 %

20.0 %

30.0 %

40.0 %

50.0 %

60.0 %

70.0 %

80.0 %

90.0 %

100.0 %

Oil Production

P/R percentage

P/R = 8.3%

Cambodia, December 200410

Cambodia, December 2004

10

Frigg Gas - NorwayGas Production - Frigg Field, Norway

116 billion Sm3 (4.1 TCF)

63.9 %

29.8 %

0

2

4

6

8

10

12

20022001200019991998199719961995199419931992199119901989198819871986198519841983198219811980197919781977

Years

Mill

ion

Sm3

0

0.2

0.4

0.6

0.8

1

1.2

Gasl Production

P/R percentage

Cambodia, December 200411

Cambodia, December 2004

11

Indonesia Field AProduction

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

2004

2005

2006

2007

2008

2009

2010

2011

2012

2013

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

2026

2027

2028

2029

2030

2031

2032

2033

0

20

40

60

80

100

120

140

Condensate (MMbbl/y)

Oil (MMbbl/y)

GAS (Bcf/y)

Cambodia, December 200412

Cambodia, December 2004

12

Attaka South, Indonesia

0

1000

2000

3000

4000

5000

6000

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013

BO

PD

0

2

4

6

8

10

12

14

16

oil (bpd)gas (MMcfd)

Cambodia, December 200413

Cambodia, December 2004

13

Troll Gas - NorwayGas Production, Troll Field, Norway

1325 Bill. Sm3 (47TCF)

8.9 %

0

5

10

15

20

25

2002200120001999199819971996199519941993199219911990

Mill

ion

Sm3

0.0 %

1.0 %

2.0 %

3.0 %

4.0 %

5.0 %

6.0 %

7.0 %

8.0 %

9.0 %

10.0 %

Build-up

Cambodia, December 200414

Cambodia, December 2004

14

Rules of ThumbTECHNICAL ASPECTS Rule of Thumb• Peak production one year/total reserves 10-12%• Decline rate 10-12%

Cambodia, December 200415

Cambodia, December 2004

15

Production curve modeling in GeoX

• Recoverable reserves- Production well drilling rate

- Low value increase production time- Initial max well production rate

- Low value prolong build up phase- Max number of oil producers

- Low value prolongs plateau- Well plateau factor

- High value prolongs plateau- Fraction produced yearly at plateau

- Low value prolongs plateau- Plateau level constraints

- Low value will prolong plateau- Fraction oil remaining at start decline

- Low value prolong plateau- Field decline rate

- Low value prolongs decline

The parameters are interdependent

and changes may have other effects that those indicated