Documenting Visual Quality Controls on the Evaluation of Petroleum Reservoir-Rocks Through Ontology-Based Image Annotation

Depositional and post-depositional (diagenetic) processes control the distribution of porosity and permeability within petroleum reservoir rocks. The understanding of these controls is essential for the construction of models for the systematic characterization and prediction of the quality (porosity, permeability) of petroleum reservoirs during their exploration and production. The description and documentation of key petrographic features is an important tool for the evaluation of reservoir quality that try to minimize the uncertainty associated to visual recognition of the features. This paper describes the role of visual controls on the petrographic analysis of reservoir rocks, and presents a knowledge-based tool that supports a workflow for the collection and documentation of visual information. This tool allows the spatial referencing of significant features in thin sections of reservoir rocks and the association of these features to a complete ontology of description. The whole process allows the preservation of original information that would support reservoir evaluation and guarantees further analysis even when the original rock sample is not available.