1. An epoch in the Pennsylvanian, dated at 303–295.1 Ma ( Harland et al. 1989) comprising the Krevyakinskian, Chamovnicheskian, and Dorogomilovskian Ages (these are also stage names in eastern European stratigraphy). The Kasimovian is preceded by the Moscovian and followed by the Gzelian Epochs.
2. The name of the corresponding eastern European series, which is roughly contemporaneous with part of the Stephanian (western Europe), and the Missourian and lower Virgilian (N. America).
"Kasimovian." A Dictionary of Earth Sciences. . Encyclopedia.com. (September 21, 2018). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/kasimovian
"Kasimovian." A Dictionary of Earth Sciences. . Retrieved September 21, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/kasimovian