Structure and Permeability of Barite Precipitation Layers Formed by Transverse Mixing in Berea Sandstone: Direct Observations and Modeling

Abstract Mixing‐limited geochemical precipitation in injection systems can cause operational issues or be harnessed for flow control. This study investigates a barite precipitation process that forms a thin, low‐permeability layer between parallel flows. Three‐dimensional core‐scale flooding experiments are conducted in Berea sandstone to induce internal transverse mixing and precipitation. X‐ray imaging, axial pressure drop observations, and core plugs extracted along the transverse direction characterize the spatial distribution of the precipitation and its effects on permeability. The transverse thickness of the resulting precipitation layer increases with axial (downstream) distance according to a (square‐root) power law. On the other hand, the reduction in (transverse) permeability within the precipitation layer is more severe near the injection sources. A high‐resolution three‐dimensional reactive transport model is reconciled with observations using an empirical porosity‐permeability relation. This understanding is foundational to furthering emerging methods for scale mitigation and the design of flow control strategies.