Jurassic

• Lias
  • Hettangian

References:

• Atkinson, J.W.; Wignall, P.B.; Page, K.N. (2020). The Hettangian-Sinemurian (Lower Jurassic) strata of Redcar, Cleveland Basin, NE England: facies and palaeoecology. Proceedings of the Yorkshire Geological Society Vol. 63 (2).
• Guex J. (1995). Ammonites hettangiennes de la Gabbs Valley Range (Nevada, USA). Mémoires de Géologie (Lausanne). No. 27, 131 p.