4
Statistical Methods for Estimating Petroleum Resources
as well as from work carried out in analogous basins. Any comprehensive
resource evaluation procedure must combine raw data with information
acquired from regional analysis and comparative studies.
The Hydrocarbon Assessment System Processor (HASP) has been
used to blend available exploration data with previously gathered information (Energy, Mines and Resources Canada, 1977; Roy, 1979). HASP
expresses combinations of exploration data and expert judgment as
probability distributions for specifi c population attributes (such as pool
area, net pay, porosity). Since this procedure was fi rst implemented,
demands on evaluation capability have steadily increased as evaluation results were increasingly applied to economic analyses. Traditional
methods could no longer meet the new demands. A probabilistic formulation for HASP became necessary and was established by Lee and
Wang (1983b). This formulation led to the development of the Petroleum
Exploration and Resource Evaluation System, PETRIMES (Lee, 1993a,
c, d; Lee and Tzeng, 1993; Lee and Wang, 1983a, b, 1984, 1985, 1986,
1987, 1990). Since then, new capabilities and features have been added
to the evaluation system (Lee, 1997, 1998). A Windows version was also
created (Lee et al., 1999). The statistical concepts and procedures used
by PETRIMES and other methods are the topics of this book.
Objectives
The objective of an assessment is to evaluate the total resource or
potential of a given region. The term resource is defi ned as the quantity of hydrocarbons of discovered and undiscovered pools; potential is
defi ned as an undiscovered quantity of hydrocarbons. However, results
of petroleum resource evaluations are usually given as aggregated
numbers representing total resources. Aggregated potential values are
not specifi c enough to be used in economic, exploration, or development planning analyses because all these processes require a knowledge of the number and size of undiscovered pools. Consequently, the
objectives of a resource assessment are to
estimate the number of yet-to-be discovered pools
•
estimate the sizes of the undiscovered pools
•
estimate the reservoir characteristics of the undiscovered pools
•
validate exploration concepts with known information
•
estimate pool-size distributions and relate these distributions
•
to geological plays
Statistical Methods for Estimating Petroleum Resources
as well as from work carried out in analogous basins. Any comprehensive
resource evaluation procedure must combine raw data with information
acquired from regional analysis and comparative studies.
The Hydrocarbon Assessment System Processor (HASP) has been
used to blend available exploration data with previously gathered information (Energy, Mines and Resources Canada, 1977; Roy, 1979). HASP
expresses combinations of exploration data and expert judgment as
probability distributions for specifi c population attributes (such as pool
area, net pay, porosity). Since this procedure was fi rst implemented,
demands on evaluation capability have steadily increased as evaluation results were increasingly applied to economic analyses. Traditional
methods could no longer meet the new demands. A probabilistic formulation for HASP became necessary and was established by Lee and
Wang (1983b). This formulation led to the development of the Petroleum
Exploration and Resource Evaluation System, PETRIMES (Lee, 1993a,
c, d; Lee and Tzeng, 1993; Lee and Wang, 1983a, b, 1984, 1985, 1986,
1987, 1990). Since then, new capabilities and features have been added
to the evaluation system (Lee, 1997, 1998). A Windows version was also
created (Lee et al., 1999). The statistical concepts and procedures used
by PETRIMES and other methods are the topics of this book.
Objectives
The objective of an assessment is to evaluate the total resource or
potential of a given region. The term resource is defi ned as the quantity of hydrocarbons of discovered and undiscovered pools; potential is
defi ned as an undiscovered quantity of hydrocarbons. However, results
of petroleum resource evaluations are usually given as aggregated
numbers representing total resources. Aggregated potential values are
not specifi c enough to be used in economic, exploration, or development planning analyses because all these processes require a knowledge of the number and size of undiscovered pools. Consequently, the
objectives of a resource assessment are to
estimate the number of yet-to-be discovered pools
•
estimate the sizes of the undiscovered pools
•
estimate the reservoir characteristics of the undiscovered pools
•
validate exploration concepts with known information
•
estimate pool-size distributions and relate these distributions
•
to geological plays