Pliocene Epoch, the geologic epoch that began about 6,000,000 years ago and lasted about 4,000,000 years. It is a subdivision of the Tertiary Period of the Cenozoic Era. Great uplifting occurred in the mountains of the northwestern United States during the Pliocene Epoch. Pliocene formations in California are sources of petroleum.
La Brea Tar Pits, an area in Hancock Park, Los Angeles, where there is a natural accumulation of sticky asphalt derived from an ancient petroleum seep.
The 1993 movie "Jurassic Park" did a good job of bringing the idea of cloning dinosaurs into popular culture. It portrayed dinosaur cloning in a way that made sense to a lot of people, but is it really possible?