A tar pit, also commonly known as an asphalt pit or asphalt lake, is a geographical occurrence where large quantities of bitumen leak to the surface and create an expansive layer of natural asphalt. This takes place when the lighter components of petroleum evaporate, leaving behind thick tar.
Tar pits are extremely sticky, and animals are unable to escape from the asphalt when they fall in. Fossils have been discovered in tar pits around the world. The few known tar pits in the world include Tierra de Brea, Carpinteria Tar Pits, La Brea Tar Pits, McKittrick Tar Pits and Lake Bermudez.