Cañadón Asfalto Formation
The Cañadón Asfalto Formation is a geological formation from the Lower Jurassic, with doubtful layers of Late Jurassic age previously referred to it. The Cañadón Asfalto Formation is located in the Cañadón Asfalto Basin, a rift basin in the Chubut Province of northwestern Patagonia, southern Argentina.
Source: Wikipedia — Cañadón Asfalto Formation (CC BY-SA 4.0)