Bernadette Craster

The Cement-to-Formation Interface in Zonal Isolation

During the completion and production phases of the well, temperature and pressure variations can cause stresses at the cement-to-formation interface. The ability of the casing cement system to maintain a seal at the cement-to-formation interface depends on the condition of the formation surface before slurry placement. The condition of a shale will depend upon the nature of the drilling fluid used, whereas the ― condition of a permeable rock will depend upon the presence and nature of the filter cake deposited during drilling. The full-length paper presents an improved understanding of chemical interactions at the cement-to-formation interface and the factors that determine bond strength and the position of the plane of failure.