The middle period of the Mesozoic Era, the Jurassic, was named for the Jura Mountains in the western Alps, near where France, Germany, and Switzerland come together. In the late 1790s, Alexander von Humboldt was examining rocks in the Jura Mountains, where the strata are mostly limestone in contrast to the abundant red beds of the underlying Triassic. Von Humboldt called the sequence the Jura-kalkstein, or Jura Limestone, in 1799, and by the 1820s French geologists were calling them the Terrains Jurassiques. The formal name Jurassic came from geologist Leopold von Buch in 1839.
In Britain, rocks of Jurassic age were being studied by William “Strata” Smith in the late 1790s. The Jurassic section in Britain was called the Lias and Oolitic Series for many years, following the usage of William Buckland and William Smith.
The name Jura is from a Celtic root word for “forest.”
While the Jurassic is known for its dinosaurs, we’ll talk about a lot of things besides dinosaurs during October. I hope you enjoy the month!
—Richard I. Gibson