Insights on the events surrounding the final drainage of Lake Ojibway based on James Bay stratigraphic sequences

► James Bay sedimentary sequences record the abrupt drainage of glacial Lake Ojibway. ► Marine waters penetrated into Lake Ojibway shortly before the final drainage event. ► Late-glacial (Cochrane) ice readvances may be linked to subglacial drainage events. ► The last ice readvance occurred simultaneously with the final drainage of the lake.