This paper concerns the characteristic-p fibers of GU (3, 2) Shimura varieties. Such Shimura varieties parametrize abelian varieties in characteristic p of dimension 5 with an action of signature (3, 2) by an order in an imaginary quadratic field in which p is inert. We completely describe the interaction of two stratifications of these Shimura varieties: the Ekedahl-Oort stratification, based on the isomorphism class of the p-torsion subgroup scheme, and the Newton stratification, based on the isogeny class of the p-divisible group. We identify which Ekedahl-Oort and Newton strata intersect.
Andrews et al. (Wed,) studied this question.