Let R be a commutative Noetherian F -finite ring of prime characteristic and let D be a Cartier algebra. We define a self-map on the Frobenius split locus of the pair (R, D) by sending a point P to the splitting prime of (R P , D P ). We prove this map is continuous, containment preserving, and fixes the D-compatible ideals. We show this map can be extended to arbitrary ideals J, where in the Frobenius split case it gives the largest Dcompatible ideal contained in J. Finally, we apply Glassbrenner's criterion to prove that the prime uniformly F -compatible ideals of a Stanley-Reisner rings are the sums of its minimal primes.