Small volcanic cones with summit craters or breached walls occur in several areas on the Moon. Most of these features have basal diameters of approximately 1 to 2 km and probably are not more than a few hundred meters in height. None have been so clearly photographed, however, as those shown in Apollo 17 metric and panoramic camera coverage of the southeastern margin of the Serenitatis basin. Two cones (A and B in fig. 30-6) approximately 10 km apart project above mare material of Eratosthenian to Imbrian age (sec. 29, part A). Between the cones, small mounds (C, D, and E in fig. 30-6) appear to be alined along the buried extension of a rille (F in fig. 30-6, mostly outside photograph) and are probably volcanic extrusions or domes. In both scale and morphology, these and other lunar cones are remarkably similar to terrestrial cinder cones (figs. 30-7 and 30-8), and their interpreted volcanic origin is not dependent on controversial criteria such as dark halos, smooth rims, or their association with materials assumed to be volcanically derived. Summit craters may be coincidental and the result of impacts on the crests of the hills, but their occurrence with cones having breached surfaces or along structural lineaments (or both) strongly favors a volcanic or volcano-tectonic origin. Like their terrestrial counterparts, these cones probably are composite structures made up of inter-layered pyroclastic material and lava flows.
