A petrophysical refresh of the bpTT fields in the Columbus Basin in Trinidad has been carried out. The objectives of the refresh were to provide continuity and consistency in petrophysical interpretations in this mature basin where over the years multiple vendors and differing interpretational approaches have been employed.
In an effort to create a more robust core data set, data gaps were identified in the existing core analyses and supplemental analysis performed. The core data set was expanded to include Co/Cw measurements on plugs from 2 wells to augment legacy data to investigate log-based water saturation methods.
New models were developed for permeability and water saturation and each of these models were calibrated against the core dataset. Permeability was re-evaluated with the new model being based on core-derived measurements and tuned to dynamic well test data to incorporate upscaling heterogeneities. Both log-based and core-based water saturation models were explored. The new core conductivity measurements provided support for the log-based method selected. Air-brine capillary pressure data have provided a key input to the development of a new saturation height function. The match between the new saturation height function water saturation and that derived from resistivity-based saturation is good, reinforcing its validity.