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Chapter
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Fig. 3.E.10 – Interactive pick
For complex analytical models, only a few parameters, or relationships between parameters,
will be determined in a unique way from the well test response. The other parameters or
missing relations will be input from other sources of information. If this missing information is
not available, the problem will remain under-specified.
The previous remark on parameter estimation is even more critical when using numerical
models, where the geometry will essentially be built from prior knowledge of the reservoir, and
only a few ‘global’ unknowns will be deduced from the test.
It is no longer a technical problem to transfer information and data directly and dynamically
between applications, and there are dozens of public or proprietary protocols to do so (OLE,
COM, DCOM, Corba, etc.). As a consequence models generated from third party applications
may be transferred and run in pressure transient analysis software. The most common
example is a ‘standard’ reservoir simulator run.
The model is generated and compared to the data, in terms of both pressure and Bourdet
derivative on the history plot, the loglog and semilog plots. In case other specialized plots are
used, the model will also be compared on these different scales. At this point, the engineer
may decide to reject the candidate model, or keep it and refine the parameter calculations.
Fig. 3.E.11 – Initial and Final model match