Geology Reference
In-Depth Information
deep
shallow
Topographic surface with false datum
No smoothing GRV=300, A=984
3x3 moving average GRV=278, A=970
5x5 moving average GRV=261, A=957
Figure 9.29
Truncation of a topographic surface with a pseudo-hydrocarbon contact, followed by calculation of area A and Gross Rock
Volume GRV above the contact, initially with no smoothing and then with two levels of smoothing. The smoothing causes the area and GRV of
the central area (red) to decrease, and the highest smoothing creates erroneous connectivity to the west (from Francis,
2006a
).
a)
Original seismic
b)
c)
Stochastic realisations
Reflectivity models from the realisations
4500 Absolute Impedance (m/s.g/cc) 11500
Figure 9.30
Separate realisations from a geostatistical inversion, all of which fit the data at the wells and honour the geostatistical model
(after Francis,
2006b
).
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