A Review

1
A Review Classification of Petroleum Resource
Base in Thailand
Anon Punnahitanon
Petroleum Engineer Mineral Fuel
Division Department of Mineral Resources
2
Objectives
Review 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
3
Outline
Resource Classification System
Reserve Definition
Resource Evaluation
Reserve Development
Resource Base _at_ end 2001
Resource Lifecycle Reserve Growth Projection
4
Resource Classification System
5
Resources (Recoverable Resources) Petroleum which
are anticipated to be commercially recovered
from known accumulations from a given date
forward
Undiscovered Resources Total estimated quantities
to be recovered from accumulations that
remainto be discovered
Discovered Resources Total discovered
deliverable quantities based on in place volume
and recovery factor
Speculative Not yet been mapped
Hypothetical Mapped prospects
Reserves Aticipated to be commercially
recovered from known accumulations from a given
date forward
Potential Resources Not commercially producible
at present
6

Reserves Petroleum which are anticipated to be
commercially recovered from known accumulations
from a given date forward
Proved Reserves Estimated with reasonable
certainty to be commercially recovered
Unproved Reserves Less certain to be recovered
than proved reserves
Probable reserves More likely than not to be
recovered
Possible reserves Less likely than likely to be
recovered
Developed Reserves Expected to be recovered form
existing wells
Undeveloped Reserves Expected to be
recovered with additional capital investment
7
Reserve Definitions
8
Reserves Contributing Factors
Reserves
Economic Conditions
Government Regulations
Historical prices/costs
Operating Methods
9
Reserves Deterministic vs. Probabilistic
10
Probabilistic Estimation
Probability
Cum. Probability
90 th percentile
Mean
Mean, P50
10 th percentile
90 th percentile
10 th percentile
Value
Value
11
Probabilistic Estimation (Contd)
Probability
Which one is the most confident ?
Mode
Geometric Mean
Median
10 th percentile
90 th percentile
Value
12
Applying Statistics in Reserves Estimation
Probabilistic estimate is very useful to form an
uncertainty range of and estimation.
Its implication is what the safe side of the
estimate and what the outrageous one are
If statistical method is to be used, each reserve
category should be assessed on different basis
to reflect its inherent different level of
confidence in data from which it is derived.
Criteria in assessing level of confidence is
qualitatively spelled out in SPE/WPC definitions.
13
Caution
Because of potential differences in
uncertainty, caution should be exercised when
aggregating different reserve classification
14
Resource / Reserve Assessment
15
Petroleum Provinces
Northern Intermontane
Central Plain
Northeastern
Gulf of Thailand
The Andaman Sea
16
Estimated Undiscovered Resources
17
Estimated Discovered Resources
Potential Recoveries
Ultimate Recovery
Natural Gas (BCF)
Oil (MMBBLS)
Condensate (MMBBLS)
924
1,025
37.3
18
Total Resource Base
19
Thailand Petroleum Proved Reserves 1979-2001
20
Field Growth or Reserve Growth
An Increase in Ultimate Recovery (Proved
Reserves Cumulative Production)
Annual Field Growth (AFG)

UR
AFG
n
n
UR
n-1
Cumulative Field Growth (CFG)

UR
UR
UR
...
CFG
n
n
2
1
21
Petroleum Resource Lifecycle
22
Natural Gas Reserve Cumulative Growth
23
Crude Oil Reserve Cumulative Growth
24
Natural Gas Resource Outlook
55.1 TCF
?
18.2 TCF
32
Undiscovered Resources Potential Recovery
36.9 TCF
68
Unproved Reserves
2002
2022
25
Crude Oil Resource Outlook
1,276 MMBBLS
?
352 MMBBLS
28
913 MMBBLS
72
2002
2023
26
Thailand Petroleum Proved Reserves
1979
-
2001
17 Years
27
Summary
DMRs Current Classification System is Reviewed
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
28
Summary (Contd)
Projection of Reserve Growth for Oil and Gas
shows that total Reserves will sustain the Growth
for the Next 20 Years
Petroleum Industry has Past Mature Stage with
Total Ultimate Recovery for Oil and Natural Gas
72 and 68 of Total Resource Base