Blackhawk Ranch Quarry

Blackhawk Ranch Quarry. A Paleontological Treasure. The Blackhawk Ranch fossil quarry is located south of Rock City on the lower slopes of Mount Diablo. During the Late Miocene, approximately 9-10 million years ago, this region was a rolling lowland. It represented the first evidence of emergence of the land around Mount Diablo after a long history of burial under the ocean. , Sycamore, elm, poplar and willow were common in the streamed forests, where animals such as Gomphotherium, a relative of the elephant, browsed among the trees, sharing the habitat with cranes, peccaries, and beavers. , Fossil evidence also indicates the presence of herbivorous animals including several kinds of horses, camels, rhinos, and pronghorns that probably favored open grasslands. There were also carnivorous sabre-toothed cats, a fox, and a very large hyena-like dog that may have preyed upon them. , Blackhawk Ranch Fossil Quarry . , A picture of this ancient landscape and the plants and animals that lived there emerged through the excavation and analysis of the concentration of fossils from the Blackhawk Ranch Quarry. , Scientist from the University of California Museum of Paleontology have carefully studied the fossils from this quarry since its discovery in 1926, as well as the Late Miocene non-marine rocks in which these fossils were found. The geological and paleontological evidence left from the ancient ecosystem lies, hidden beneath the grassy slopes on the south side of the mountain.