Clay minerals, carbon storage, and effects of observational scale on computational models

Geologic features such as producing or depleted hydrocarbon fields, coal beds, or saline aquifers provide opportunities for subsurface long-term storage of CO2. Computational models offer a means of evaluating, comparing, and selecting storage reservoirs on criteria such as ease of injection, storage capacity, escape potential, and monitoring requirements. Models require adjustments to accommodate geologic anisotropies and heterogeneities at a wide variety of observational scales. Statistical data mining of preexisting data and information obtained during site investigations provides methods of identifying significant geologic scales. Clay minerals relate to most concerns about subsurface storage of CO2. Quantitative identification of clay minerals and their physical and geochemical properties constitute a critical key to evaluating potential storage sites for CO2.