1. An age in the Middle Miocene, preceded by the Langhian, followed by the Tortonian, and dated at 14.2–10.4 Ma ( Harland et al., 1989).
2. The name of the corresponding European stage, which is roughly contemporaneous with the Helvetian (Europe), upper Luisian and lower Mohnian (N. America), Lillburnian (New Zealand), and Bairnsdalian (Australia). The stratotype is in the Scrivia Valley, Italy.
"Serravallian." A Dictionary of Earth Sciences. . Encyclopedia.com. (November 15, 2018). https://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/serravallian
"Serravallian." A Dictionary of Earth Sciences. . Retrieved November 15, 2018 from Encyclopedia.com: https://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/serravallian