The focus on unconventional opportunities is growing in several basins worldwide. As unconventional opportunities grow and develop, a reliable evaluation of unconventional resources and reserves poses a challenge to our industry. The novelty of many unconventional plays implies limited historical trends. Also, because no two unconventional plays are the same and variations within a play can yield significantly different results, the evaluation of such reservoirs is a challenge.
In the case study presented, a workflow is described in which trap wash overlying a fractured basement was successfully evaluated for the first time using the wireline-conveyed dual packer interval pressure transient testing (IPTT) technique. An integrated petrophysical evaluation including nuclear magnetic resonance (NMR) was used for hydrocarbon saturation and permeability determination in conjunction with classical openhole logs and other advanced logs. Borehole microimager-derived results were useful in detailed fracture characterization and optimization of the dual packer position for a successful IPTT operation that proved oil from the section above fractured basement.