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The heart of any reservoir modeling effort is the structural model
built by using the interpreted horizons and faults. The current structural modeling technologies
used in E&P software are plagued with problems including their
inability to handle complex structural frameworks with a large number of
faults in the range of one hundred or above. For example, modeling a
reservoir with 200 faults could take an experienced modeler 3 months or
more when using pillar gridding. As a result, all
new structural modeling technologies avoid the inefficient pillar gridding approach.
Prism Seismic developed a fast and intuitive structural modeling technology
that enables the geoscientists to build a complex structural framework in
hours not days. This technology does not use pillars and handles in an
intuitive way the faults and horizons as objects that need to form a
geologically consistent framework through multiple intersections. Prism
Seismic structural modeling
technology is available in CRYSTAL where a large number of tools allow the
geoscientist to use the seismically interpreted horizons and faults to
build a structural framework in the time domain. The derived structural framework in time
is depth converted using Prism Seismic time-depth conversion that utilizes the velocity information
available in the wells and any velocity information provided by the seismic
processor. In the event seismic data
is not available, the structural framework could also be built in
the depth domain using depth maps
and faults derived from curvature analysis and other methods that do not
rely on seismic interpretation.
Prism Seismic structural
modeling technology is able to handle any type of fault system and any
number of faults. The faulted framework built in CRYSTAL
could be grided with rectangular gridblocks that provide geocellular
models ready for property and fracture modeling. Two geocellular
grids are available in CRYSTAL : 1) a trimmed grid
where cells are truncated by faults and form gridblocks
that have more than 6 faces suitable for volumetrics
calculations, and 2) a perfectly rectangular gridblock
with only 6 faces
suitable for reservoir simulators. A major characteristic of Prism
Seismic geocellulars 3D grids is the vertical columns that
ensure correct reservoir simulation results. Geocellular
grids with tilted columns near faults provide wrong results when used to
simulate processes driven by gravity (for example gravity drainage).
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