Queen Sandstones have recently been the target of new drilling programs, especially along the southern margins of the Central Basin Platform. This activity, coupled with continued development of the more established Queen Fields, indicates that the Queen Sandstones deserve the focus of this integrated formation evaluation study.
The Queen Sandstones are very fine-grained, arkosic, and contain variable amounts of anhydrite, dolomite, and problematic clay minerals making them difficult to petrophysically evaluate. Consequently, operators need to acquire and utilize rock property data to aid them in their formation evaluation.
This integrated formation evaluation approach consists of establishing a rock property database that is integrated with log and well test information in order to establish sets of pay and non-pay criteria for the various Queen Sandstone rock types. Besides improving formation evaluation, this study provides participating companies with data and interpretations for a better understanding of geological concepts, and prediction of reserves and producibility.
Reservoir rock types from conventional and rotary sidewall cores and their measured petrophysical properties are correlated to log parameters and production test data. With this approach, pay and non-pay criteria is established resulting in improved formation evaluation. Additionally, rock-fluid compatibility tests are performed on selected samples to determine which drilling, completion, and/or injection fluids can be safely utilized without causing formation damage.