Presenting a Multifaceted Approach to Unconventional Rock Typing and Technical Validation-Case Study in the Permian Basin and Impacts on Reservoir Characterization Workflows

摘要

Numerous integrative approaches can be taken to link subsurface rock-type characterization to related openhole wireline log attributes. In this study, focus and emphasis was geared towards developing rock-typing models that link depositional environments to petrophysical property space trends and variations to then guide subsurface modeling. Multiple technical paths were taken, and tools used to link observed rock types in full-diameter conventional cores and related measured geological attributes to electrofacies and the refined petrofacies characterization. The data integration used a significant volume of core analytical and openhole wireline log suites including a base suite of triple-combo data (gamma ray, neutron, density, and resistivity) and expanding to include resistivity borehole image data. We present how the addition of various subsurface datasets impacts rock-typing efforts and accuracy. A cluster-based, least-mean-squares analytical result is observed and discussed in an unsupervised model application and is compared to a supervised model application. The relative importance of various attributes is discussed and used to recommend a workflow for Permian-focused rock typing that allows the subsurface characterization to be extrapolated to regional (basinwide) and local (single-well) scales. In short, we focus on sharing a workflow to effectively link core description (sedimentologic observations) and raw log analytics to refine and upscale rock property distributions for use in sequence stratigraphic frameworks, regional basin depositional models and multiscale modeling efforts.