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Statistical Methods for Estimating Petroleum Resources
incorrectly estimated, appreciated, or depreciated, or if the rankings
are altered, then the expected value of the remaining potential will be
affected. Provided that the geology of a play is well understood and
documented, the expected value should provide a reliable estimate of
play potential.
It should be noted that given the possible truncation of the pool size
data set, estimates of the resources in a play should not be considered as
the ultimate resource for that play. The results of an assessment are for
the pool size data set used, so the model only predicts the existence of
undiscovered pools based on that data set. The probable play potential
can also be derived (see Chapter 5).
Step 8: Computing Play Resource Distribution
One way to report the range of the play resource is to choose values at
the 0.90 probability prediction interval (95th and 5th percentiles) of the
play resource distribution.
Procedure for Estimating Conceptual Plays
Conceptual Plays from a Mature Basin
Unlike assessments for frontier basins, where the resources of conceptual
plays may be determined from geological judgment, the number and size
of conceptual plays that might exist in a mature basin can be estimated
from NDSCV. Figure 6.1 shows the play resource discovery sequence for
Devonian gas plays. This sequence was constructed after evaluating all
mature Devonian plays and compiling their respective discovery dates.
Figure 6.2 shows the mature play-by-rank plot. Assuming that the
Devonian mature plays belong to a single population, NDSCV can be
used to estimate the size of each conceptual play and the total number
of plays within the Devonian basin. As in the pool-size-by-rank plot,
dots represent matched discovered plays and boxes represent plays yet
to be discovered.
Conceptual Plays from a Frontier Basin
Step 1: Formulating Play Defi nitions
A conceptual play has both geographic and stratigraphic limits and is
confi ned to a basin or part of a basin, or a structural unit or part of it,
and is confi ned to one or more formations.
Statistical Methods for Estimating Petroleum Resources
incorrectly estimated, appreciated, or depreciated, or if the rankings
are altered, then the expected value of the remaining potential will be
affected. Provided that the geology of a play is well understood and
documented, the expected value should provide a reliable estimate of
play potential.
It should be noted that given the possible truncation of the pool size
data set, estimates of the resources in a play should not be considered as
the ultimate resource for that play. The results of an assessment are for
the pool size data set used, so the model only predicts the existence of
undiscovered pools based on that data set. The probable play potential
can also be derived (see Chapter 5).
Step 8: Computing Play Resource Distribution
One way to report the range of the play resource is to choose values at
the 0.90 probability prediction interval (95th and 5th percentiles) of the
play resource distribution.
Procedure for Estimating Conceptual Plays
Conceptual Plays from a Mature Basin
Unlike assessments for frontier basins, where the resources of conceptual
plays may be determined from geological judgment, the number and size
of conceptual plays that might exist in a mature basin can be estimated
from NDSCV. Figure 6.1 shows the play resource discovery sequence for
Devonian gas plays. This sequence was constructed after evaluating all
mature Devonian plays and compiling their respective discovery dates.
Figure 6.2 shows the mature play-by-rank plot. Assuming that the
Devonian mature plays belong to a single population, NDSCV can be
used to estimate the size of each conceptual play and the total number
of plays within the Devonian basin. As in the pool-size-by-rank plot,
dots represent matched discovered plays and boxes represent plays yet
to be discovered.
Conceptual Plays from a Frontier Basin
Step 1: Formulating Play Defi nitions
A conceptual play has both geographic and stratigraphic limits and is
confi ned to a basin or part of a basin, or a structural unit or part of it,
and is confi ned to one or more formations.