Geoscience Reference
In-Depth Information
Fig. 7.8
Example of full immersive visualisation. New technology includes fully immersive
displays where the data are projected onto each wall and the floors and ceilings of a specially
designed room. This allows the interpreter to walk through the data, examining details of the
reservoir from all angles.
volume will increase to fill much of the 3-D dataset. If the picking is successful, then
a 3-D volume corresponding to the 'seismic pay' has been created. This may or may
not correspond to the real pay volume. In particular, the limited resolution of seismic
means that seismic connectivity is not the same as connectivity between sands in the
real earth. Production behaviour or prospect validity may be strongly affected by sands
too thin to image seismically.
Figure 7.5
shows another useful display. Part of the data is rendered transparent,
leaving only those amplitudes that might correspond to reservoir. For example, all
amplitudes less than 100 could be removed completely, and amplitudes in the range
100-128 could be made progressively more opaque. This gives an efficient means of
viewing and understanding the 3-D geometry of a reservoir body. This is readily grasped
if the semi-transparent cube can be rotated in real time, so that it can be inspected from a
variety of angles in quick succession. Setting up the transparency function can be tricky;
the idea is to make the voxels of interest bright while removing (making transparent)
the rest. Trial and error are inevitable, but a study of well impedances and calculated