- The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from about 174.1 to 163.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations containing land animal fossils include the Forest Marble Formation in England, the Kilmaluag Formation in Scotland, the Calcaire de Caen of France, the Daohugou Beds in China, the Itat Formation in Russia, the Tiouraren Formation of Niger, and the Isalo III Formation of western Madagascar.
- Black Hills (Wikipedia)
The Black Hills is an isolated mountain range rising from the Great Plains of North America in western South Dakota and extending into Wyoming, United States. Black Elk Peak, which rises to 7,242 feet (2,207 m), is the range’s highest summit. The name of the range in Lakota is Pahá Sápa. It encompasses the Black Hills National Forest. It formed as a result of an upwarping of ancient rock, after which the removal of the higher portions of the mountain mass by stream erosion produced the present-day topography. The hills are so called because of their dark appearance from a distance, as they are covered in evergreen trees.