The idea of SBT is to
Assess formation pressure in perforated formation units.
Fig. 1. SGS in oil producer |
The survey assumes that
The survey is applicable for wells with one perforated unit with no integrity issues (behind casing communications, active leaks or leaky bottom-hole)
The survey is applicable for wells with multiple perforations providing that all perforated units have the same formation pressure so that well doe snot develop a cross-flow between perfoations during the survey.
In most practical cases the above conditions are not met and SGS maybe highly misleading.