  In this paper we study the geometry of good reductions of Shimura varieties
of abelian type. More precisely, we construct the Newton stratification,
Ekedahl-Oort stratification, and central leaves on the special fiber of a
Shimura variety of abelian type at a good prime. We establish several basic
properties of these stratifications, including the non-emptiness, closure
relation and dimension formula, generalizing those previously known in the PEL
and Hodge type cases. We also study the relations between these
stratifications, both in general and in some special cases, such as those of
fully Hodge-Newton decomposable type. We investigate the examples of
quaternionic and orthogonal Shimura varieties in details.
