Yep, a two part marine epoxy. Open it up lightly with a knife and put the mixed epoxy as deep in as possible. Use a vise or vise grips and clap seperated area closed and let set for advised time on the epoxy instructions. Make sure to clean excess epoxy off while wet or its gonna be a pain to remove and be ugly. After a full day to cure it should be ready to rip groomers.
Get yourself a couple of thin blocks of wood to place between the clamps and the topsheet & base of the board. Once glued, You'll need to clamp it Tight and you don't want to further damage/dent the top or base. (..blocks will better distribute the pressure evenly over glued area as well.)