The Bitter Springs anomaly
Carbon isotopes swing worldwide, hinting the whole planet rolled over on its axis.
- When
- Known to
- ± 20 million years
- Era
- Neoproterozoic, Proterozoic
A large negative carbon isotope excursion around 810 to 800 million years ago appears in sections on several continents. One striking explanation is true polar wander — the entire solid Earth rotating relative to its spin axis, moving continents through climate zones without any plate motion. Alternatives invoke changes in ocean circulation or organic carbon burial. It marks the start of the unstable interval leading into Snowball Earth.