Method for providing zonal isolation in an underground wellbore

A method for providing zonal isolation in an underground wellbore, the method comprising creating a stacked cement and cured resin column that provides a zonal isolation seal within the wellbore employing steps of:

• injecting into the wellbore at least one slug of a cement slurry;
• in addition to said injecting into the wellbore the at least one slug of a cement slurry, injecting into the wellbore at least one additional slug of a resin composition comprising a curable resin, a filler, a swelling agent, a curing initiator and a crosslinking retarding agent, which delays curing of the resin to permit pumping the composition into the wellbore;
• creating a stacked cement and resin column by forming alternating layers of the at least one slug of the cement slurry and the at least one additional slug of the resin composition within the wellbore;
• and
• allowing the cement slurry and resin composition in the stacked cement and resin column to cure.