Snow Hill Island Formation

The Snow Hill Island Formation is an Early Maastrichtian geologic formation found on James Ross Island, James Ross Island group, Antarctica. Remains of a paraviantheropodImperobator antarcticus have been recovered from it, as well as the elasmarian ornithopods Trinisaura santamartaensis and Morrosaurus antarcticus, the ankylosaurianAntarctopelta oliveroi, and the shark Notidanodon sp. Alongside these described genera are also the remains of indeterminate elasmosaurids, lithostrotian titanosaurs and an indeterminate pterosaur.

The uppermost portion of the Gamma Member containing the Santa Marta Cove fauna is dated to the late Campanian, approximately 73.4 million years ago, while the younger Cape Lamb Member is from the latest Campanian to early Maastrichtian, with the uppermost portion dated to 69.7 million years ago.