A stage in the European Early Jurassic (183–175.6 Ma ago; Int. Commission on Stratigraphy, 2004), preceded by the Pliensbachian, followed by the Aalenian, and roughly contemporaneous with the mid-Uroroan (New Zealand). See also lias.
科学参考收录了60776条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。