  A convex geometric hypergraph (abbreviated cgh) consists of a collection of
subsets of a strictly convex set of points in the plane. Extremal problems for
cgh's have been extensively studied in the literature, and in this paper we
consider their corresponding saturation problems. We asymptotically determine
the saturation number of two geometrically disjoint $r$-tuples. Further,
amongst the eight nonisomorphic $3$-uniform cgh's on two edges, we determine
the saturation number for seven of these up to order of magnitude and the
eighth up to a log factor.

Combinatorics