The Bitter Springs anomaly (BSA) represents a sharp drop in δ13Ccarb concentrations on average by 8‰, for 8 million years during the Tonian period.
[2] In North-Western Canada, the BSA is contained within the Ram Head formation, which has been confined to 1005–775 Myrs in age via zircon dating.
The anomaly spans a section of approximately 175 meters, marked by high energy stromatolite and ooid deposits.
[3][1] Notably, the anomaly is associated with flooding plains in Canada, and the Scandinavian manifestations are capped by sub-aerial exposure surfaces on both ends.
[5][1] As only several formations are known to document the anomaly at this time, it is still unknown if it was global or constrained to shallower depths of carbonate platforms.