Ediacaran
Geologic period
The Ediacaran is a geological period of the Neoproterozoic era that spans 96 million years from the end of the Cryogenian period at 635 Mya to the beginning of the Cambrian period at 538.8 Mya. Wikipedia
Era: Neoproterozoic
Occurred: 635 million years ago - 541 (+/- 1) million years ago
Chronological unit: Period
Lower boundary definition: Worldwide distinct cap carbonates. Beginning of a distinctive pattern of secular changes in carbon isotopes
Lower boundary GSSP: Enorama Creek section, Flinders Ranges, South Australia; 31°19′53″S 138°38′00″E / 31.3314°S 138.6334°E
Lower GSSP ratified: March 2004
Stratigraphic unit: System