222
Index
cost/price regimes, 167
cost truncation barrier, removing, 167
covariance, 44–5, 119, 121–2, 124, 137
impact on pool-size
distribution, 124
matrix of random variables, 44–5, 123
positive or negative, 122, 124, 137
between variables, 137
creaming method, 153, 169–70
curve fi tting. See fi tting curves and
lines
density function, 31, 42, 44, 62–3,
131–2
joint, 31, 44
deposition, 26, 31, 87, 109, 159
deposit volume, 40
Devonian clastics, 103–4
Devonian gas play, 85, 91, 100,
146–8
Devonian sandstone play, 21
diagenesis, 8, 11
DIAGEN program, 160
discovery, 6, 13–14, 16, 20, 26, 28, 30,
42–3, 60, 63, 73, 82, 120, 144,
147, 169–70
data, 7, 13, 20, 26, 28
date, 34, 140, 146–7
factors infl uencing, 28
order of, 26, 40, 42, 169
probability proportional to size, 16,
28–9, 38
process, 13, 16, 18, 25, 27–9, 31, 36
likelihood function, 30
as sampling process, 16, 28
simulation of, 18, 61, 63, 71, 78
stage, large vs. small pools, 16, 28
discovery process model, 5, 13, 22–3,
27–30, 33–4, 36, 40, 43, 45,
61, 63, 85, 87–8, 106, 120, 161,
166–8, 170, 174–5
controlling factors of, 87
estimation of pool-size distribution
and number of pools, 5, 26, 28,
30, 32, 85, 145
and “marble fi shing,” 87
discovery sequence, 14, 19–20, 27, 30,
32, 39–40, 43–4, 63, 66–70, 82,
144, 146–7, 164, 170
and absence of small pools, 20, 87–8
simulated, 63
distribution. See also fi eld-size,
gamma, lognormal, numberof-pools/prospects, Pareto,
play, pool-size, population,
probability, superpopulation,
Weibull
completely specifi ed, 89
continuous, 12–13, 16–18
cumulative, 12–13, 33, 42
density of, 28, 33, 43
determining shape of, 28–9, 34,
62–3, 71, 88–91, 144
discrete, 12, 16–17, 36, 91
of facies, 14
fractal, 191, 173
function, empirical, 34, 54, 74, 91,
100–101, 144
hypothesized, 89–91
J-shaped, 28, 62, 64–5, 100–101, 105
nonparametric, 13, 17, 34, 38, 55, 91
observed, 26, 89, 101, 167
posterior, 27, 38–9
power normal, 90–91, 94, 105, 173
prior, 13, 33, 38, 50, 91, 103
tails, 21, 89–91, 93, 102, 126, 133
distributional assumption, 34, 88, 91
drilling decisions, classifi cation
of, 72–3
drilling effi ciency, 72–3, 163
drill stem test, 19–20, 85, 112, 140,
143–4
recoveries, 20, 85, 143–4
dry hole, 140, 142, 144
economic analysis, 4–5, 26–7, 51, 105,
116, 135, 145, 154, 170–71, 175
and aggregated potential values, 4
and conditional distribution of
pool area and net pay, 116,
135, 145
economic research, 163
economic truncation, 87–8, 144, 167, 170
Elk Point reef carbonate, 18
enhanced oil recovery techniques, 120
estimation error, 50
from lognormal distribution
approximation, 71, 102, 105
estimation uncertainty, 11, 26, 52–3,
55, 60, 167
reduction of, 55, 60, 77, 80
expected play potential, 58–60, 82, 84,
145–6
expert judgment, 4, 109, 136, 147, 165
expert knowledge, 20, 33, 128
exploration, 4–5, 13, 18, 26, 28, 51, 86,
105, 109–10, 150, 167, 169, 171
data, 4, 13–14, 34
biased, 25–6, 28, 174
decision making, selective, 26–7
Index
cost/price regimes, 167
cost truncation barrier, removing, 167
covariance, 44–5, 119, 121–2, 124, 137
impact on pool-size
distribution, 124
matrix of random variables, 44–5, 123
positive or negative, 122, 124, 137
between variables, 137
creaming method, 153, 169–70
curve fi tting. See fi tting curves and
lines
density function, 31, 42, 44, 62–3,
131–2
joint, 31, 44
deposition, 26, 31, 87, 109, 159
deposit volume, 40
Devonian clastics, 103–4
Devonian gas play, 85, 91, 100,
146–8
Devonian sandstone play, 21
diagenesis, 8, 11
DIAGEN program, 160
discovery, 6, 13–14, 16, 20, 26, 28, 30,
42–3, 60, 63, 73, 82, 120, 144,
147, 169–70
data, 7, 13, 20, 26, 28
date, 34, 140, 146–7
factors infl uencing, 28
order of, 26, 40, 42, 169
probability proportional to size, 16,
28–9, 38
process, 13, 16, 18, 25, 27–9, 31, 36
likelihood function, 30
as sampling process, 16, 28
simulation of, 18, 61, 63, 71, 78
stage, large vs. small pools, 16, 28
discovery process model, 5, 13, 22–3,
27–30, 33–4, 36, 40, 43, 45,
61, 63, 85, 87–8, 106, 120, 161,
166–8, 170, 174–5
controlling factors of, 87
estimation of pool-size distribution
and number of pools, 5, 26, 28,
30, 32, 85, 145
and “marble fi shing,” 87
discovery sequence, 14, 19–20, 27, 30,
32, 39–40, 43–4, 63, 66–70, 82,
144, 146–7, 164, 170
and absence of small pools, 20, 87–8
simulated, 63
distribution. See also fi eld-size,
gamma, lognormal, numberof-pools/prospects, Pareto,
play, pool-size, population,
probability, superpopulation,
Weibull
completely specifi ed, 89
continuous, 12–13, 16–18
cumulative, 12–13, 33, 42
density of, 28, 33, 43
determining shape of, 28–9, 34,
62–3, 71, 88–91, 144
discrete, 12, 16–17, 36, 91
of facies, 14
fractal, 191, 173
function, empirical, 34, 54, 74, 91,
100–101, 144
hypothesized, 89–91
J-shaped, 28, 62, 64–5, 100–101, 105
nonparametric, 13, 17, 34, 38, 55, 91
observed, 26, 89, 101, 167
posterior, 27, 38–9
power normal, 90–91, 94, 105, 173
prior, 13, 33, 38, 50, 91, 103
tails, 21, 89–91, 93, 102, 126, 133
distributional assumption, 34, 88, 91
drilling decisions, classifi cation
of, 72–3
drilling effi ciency, 72–3, 163
drill stem test, 19–20, 85, 112, 140,
143–4
recoveries, 20, 85, 143–4
dry hole, 140, 142, 144
economic analysis, 4–5, 26–7, 51, 105,
116, 135, 145, 154, 170–71, 175
and aggregated potential values, 4
and conditional distribution of
pool area and net pay, 116,
135, 145
economic research, 163
economic truncation, 87–8, 144, 167, 170
Elk Point reef carbonate, 18
enhanced oil recovery techniques, 120
estimation error, 50
from lognormal distribution
approximation, 71, 102, 105
estimation uncertainty, 11, 26, 52–3,
55, 60, 167
reduction of, 55, 60, 77, 80
expected play potential, 58–60, 82, 84,
145–6
expert judgment, 4, 109, 136, 147, 165
expert knowledge, 20, 33, 128
exploration, 4–5, 13, 18, 26, 28, 51, 86,
105, 109–10, 150, 167, 169, 171
data, 4, 13–14, 34
biased, 25–6, 28, 174
decision making, selective, 26–7