La Meseta Formation
The La Meseta Formation is a sedimentary sequence deposited during the Eocene. The formation is found on Seymour Island, Antarctica.Description
La Meseta Formation lies unconformably on the Cretaceous Lopez de Bertodano Formation. It is an approximately thick sequence of poorly consolidated sandstones and siltstones. The depositional environment was probably coastal, deltaic or estuarine in character. The top of the sequence is an erosional unconformity to Pleistocene glacial gravels. La Meseta Formation is one of the sequences that make up the fill of the Late Jurassic to Paleogene James Ross Basin.Fossil content
La Meseta Formation is extremely rich in fossils. Among mammals, the meridiungulata Antarctodon and Trigonostylops have been found in the formation. as well as marsupial Microbiotheria. It is famous for its penguin fossils, for example the two genera Archaeospheniscus and Palaeeudyptes. Other bird fossils include Dasornis, a genus of pseudotooth birds. There are also an abundance of trace fossils. Diplocraterion, Helminthopsis, Muensteria, Oichnus, Ophiomorpha, Skolithos, Teredolites and Zapfella have been described. Over 35 species and 26 families of fish have been described from the Ypresian Cucullaea bed.Mammals
- Antarctodolops
- Llanocetus
- Basilosaurus
- Derorhynchus
- Trigonostylopidae indent
Birds
- Anthropornis grandis
- Archaeospheniscus wimani
- Archaeospheniscus lopdelli
- Dasornis
- Delphinornis larseni
- Palaeeudyptes antarcticus
- Palaeeudyptes gunnari
- Palaeeudyptes klekowskii
