1A Review & Classificationof

Petroleum Resource Base in Thailand

Anon PunnahitanonPetroleum EngineerMineral Fuel DivisionDepartment of Mineral Resources

ObjectivesReview Current Petroleum Resource Classification System Currently used in DMR

Reclassify Petroleum Resources & Reserves into the Same Classification System

Estimate Petroleum Resource Base

Outlook on the Petroleum Industry of the Country

Outline

Resource Classification SystemReserve DefinitionReserve DefinitionResource EvaluationReserve DevelopmentResource Base @ end 2001Resource Lifecycle & Reserve GrowthResource Lifecycle & Reserve Growth Projection

Resource Classification SystemResource Classification System

2Resources (Recoverable Resources)Petroleum which are anticipated to be commercially recovered from known accumulations from a given date forward

Undiscovered ResourcesDiscovered Resources Undiscovered ResourcesTotal estimated quantities to be recovered from accumulations that remainto be discovered

HypotheticalMapped prospects

SpeculativeNot yet been mapped

Discovered ResourcesTotal discovered deliverable quantitiesbased on in place volume and recovery factor

ReservesAticipated to be commercially recovered from known accumulations from a given date forward

Potential ResourcesNot commercially producible at present

ReservesPetroleum which are anticipated to be commercially recovered from known accumulations from a given date forward

Proved Reserves Unproved ReservesProved ReservesEstimated with reasonable certainty to be commercially recovered

Unproved ReservesLess certain to be recovered than proved reserves

Probable reservesMore likely than notto be recovered

Possible reservesLess likely than likely to be recovered

Developed ReservesExpected to be recovered form existing wells

Undeveloped ReservesExpected to be recoveredwith additional capital investment

Reserve DefinitionsReserve Definitions Reserves

Reserves Contributing Factors

Reserves

Economic Conditions Government Regulations

Historical prices/costs

Operating Methods

3ReservesReservesDeterministic vs.

Probabilistic

Probabilistic Estimation

Probability Cum. Probability90 th percentile

Possible ?

V l

90 th percentile10 th percentile

Mean

Value

10 th percentile

Mean, P50

Probable ?

Value Value

Proved ?

Probabilistic Estimation (Contd)Probability

Which one is the most confident ?

Mode

Geometric Mean

Median

Value

90 th percentile10 th percentile

Probabilistic estimate is very useful to form an uncertainty range of and estimation.

Applying Statistics in Reserves Estimation

If statistical method is to be used, each reserve category should be assessed on different basis to reflect its inherent different

range of and estimation.

Its implication is what the safe side of the estimate and what the outrageous one are

level of confidence in data from which it is derived.

Criteria in assessing level of confidence is qualitatively spelled out in SPE/WPC definitions.

4CautionBecause of potential differences in uncertainty,

caution should be exercisedwhen aggregating different reserve classification

Resource / ReserveAssessment

Petroleum Provinces

Northern IntermontaneNorthern Intermontane

Central PlainNortheasternGulf of ThailandThe Andaman Sea

Gas (TCF) Oil (MMBBL) Condensate (MMBBL)

Basins

Low High Low High Low High

Estimated Undiscovered Resources

Low High Low High Low HighOnshore Tertiary

0.2 0.5 120.0 260.0 - -

Pre-Tertiary 3.5 11.0 - - 1.0 5.0

Gulf of Thailand

11.0 33.0 110 350 225.0 600.0

Andaman Sea

2.5 7.5 30.0 100.0 30.0 100.0

Total 17.2 52.0 260.0 710.0 256.0 705.0

5 Oil (MMBBL)

Condensate (MMBBL)

Natural Gas (BCF)

Estimated Discovered ResourcesPotential Recoveries

( ) ( ) ( )Gulf of Thailand 92.42 7.29 633.77 Onshore NA NA NA

Possible Reserves 253.4 321.0 7,617.8

Ultimate RecoveryOil

(MMBBLS)Condensate(MMBBLS)

Natural Gas(BCF)

Probable Reserves 156.9 245.1 9,654.4 Proved Reserves 325.0 262.4 13,301.6 Cumulative Production 188.6 196.5 6,739.5

924 1,025 37.3

Oil (MMBBL)

Condensate (MMBBL)

Natural Gas (BCF)

Undiscovered Resources 260 256 17 200 0

Total Resource Base

Undiscovered Resources 260 256 17,200.0Potential Recovery 92.4 7.3 633.8Possible Reserves 253.4 321.0 7,617.8 Probable Reserves 156.9 245.1 9,654.4Proved Reserves 325.0 262.4 13,301.6Cumulative Production 188.6 196.5 6,739.5

Total 1 276 3 1 288 3 55 147 1 Total 1,276.3 1,288.3 55,147.1

250

300

350

12,000

14,000

16,000

250

300

350

12,000

14,000

16,000

Thailand Petroleum Proved Reserves 1979-2001

100

150

200

250

M

M

B

B

L

s

4,000

6,000

8,000

10,000

B

C

F

100

150

200

250

M

M

B

B

L

s

4,000

6,000

8,000

10,000

B

C

F

0

50

1979

1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

-

2,000

Oil Condensate Gas

0

50

1979

1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

-

2,000

Oil Condensate Gas

Field Growth or Reserve Growth

An Increase in Ultimate Recovery(Proved Reserves + Cumulative Production)

Annual Field Growth (AFG)

URAFGn =UR n-1

n

UR *

Cumulative Field Growth (CFG)

CFGn = UR 1 nUR *2 ...*

6100

120i

a

l

%

Petroleum Resource Lifecycle

40

60

80

t

i

m

a

t

e

R

e

c

o

v

e

r

y

P

o

t

e

n

t

i

0

20

U

l

t

Proved + Production Unproved Potential Undiscovered Resources

100

120

F

a

c

t

o

r

100

120

F

a

c

t

o

r

Natural Gas Reserve Cumulative Growth

y = 71.106Ln(x) - 167.7540

60

80

u

m

u

l

a

t

i

v

e

G

r

o

w

t

h

F

y = 71.106Ln(x) - 167.7540

60

80

u

m

u

l

a

t

i

v

e

G

r

o

w

t

h

F

20

0 10 20 30 40 50

Year

C

u

20

0 10 20 30 40 50

Year

C

u

35

40

45

F

a

c

t

o

r

35

40

45

F

a

c

t

o

r

Crude Oil Reserve Cumulative Growth

y = 23.268Ln(x) - 47.113

10

15

20

25

30

m

u

l

a

t

i

v

e

G

r

o

w

t

h

F

y = 23.268Ln(x) - 47.113

10

15

20

25

30

m

u

l

a

t

i

v

e

G

r

o

w

t

h

F

5

10

0 10 20 30 40 50Year

C

u

m

5

10

0 10 20 30 40 50

C

u

m

18.2TCF32%

Natural Gas Resource Outlook

?55.1 TCF

Undiscovered Resources

68%

36.9 TCFTCF

Unproved Reserves

+ Potential Recovery

2002 2022

p

7Crude Oil Resource Outlook

913 MMBBLS352

MMBBLS28% ?1,276 MMBBLS

72%

913 MMBBLS

2002 2023

50

60

50

60

Thailand Petroleum Proved Reserves 1979-2001

20

30

40

20

30

40 OilCondensateGas

OilCondensateGas

17 Years10

1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004

10

1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004

17 Years

DMRs Current Classification System is Reviewed

Summary

Estimated Petroleum Resource Base for Oil, Condensate and Natural Gas are 1,276 MMBBLS, 1,288 MMBBLS, and 55 TCF, Respectively

Total Reserves are 924 MMBBLS Oil, 1025 MMBBLS Condensate, and 37.3 TCF Natural Gas

Summary (Contd)

Projection of Reserve Growth for Oil and Gas shows that total Reserves will sustain

Petroleum Industry has Past Mature Stage with Total Ultimate Recovery for Oil and Natural Gas 72% and 68 % of Total

Gas shows that total Reserves will sustain the Growth for the Next 20 Years

Natural Gas 72% and 68 % of Total Resource Base