Hettangian

赫特唐阶

释义与例句

name
  1. 1.

    The earliest age of the Jurassic period, from 199.3–201.3Ma

    生物 地质
  2. 2.

    The corresponding lowest stage of the Jurassic system, marked by the lowest strata in which the neoammonite genus Psiloceras appears.

词源

From French Hettange, now Hettange-Grande, a commune in northeastern France, (German Hettingen, Luxembourgish (Lorraine Franconian) Hetténgen).

来源：wiktionary