Abstract
Wellbore storage effect is a common issue in pressure transient analysis which masks the early response of reservoir behaviour and flow regime. It distorts most of valuable pressure data especially in cases with large well volume, high mechanical damage, and compressible fluids. As a consequence, the early response of fast-occurring phenomena such as dual porosity transition, linear flow and bilinear flow can be partially or completely distorted.
In this paper, a procedure is proposed and applied to enhance the applicability and effectiveness of direct deconvolution methods for calculation of wellbore storage-free pressure response. The proposed procedures are tested and validated in large-volume wells in the Middle East where wellbore storage has distorted the whole well test data points. We found that these methods can be followed to identify early flow regime types and to calculate permeability, skin and natural fractures properties with the lowest uncertainty.