UC Berkeley

This study evaluates the type and amounts of clays and clay minerals present in typical oil-producing formations that may be candidates for application of EOR methods. After identification of the clay minerals present, tests are run on the extracted clay fractions to determine cation-exchange capacities (CEC's), surface areas, and chemical-loss characteristics. Flood tests are run on core samples to evaluate the magnitude of chemical loss and to note the change in flow characteristics while different fluids, which might be used in EOR operations, are flowed through the core. This background material is used to test predictive equations developed for screening reservoirs for EOR applications and for optimizing process variables. Techniques to counter the effects of rock/fluid interactions are considered.