Australia: The Land Where Time Began

A biography of the Australian continent 

Double Flood Basalts and Plume Head Separation at the Discontinuity at 660-km depth

Major eruptions occurring at 2 distinct times separated by between 20 My and 90 My are displayed by several of the flood basalt provinces around the world. The authors¹ suggest that a starting plume head can be separated from its trailing conduit as it passes the interface between the upper and lower mantle, therefore it may be the trigger for these double flood basalts. Eventually the first flood basalt event will be triggered by the detached plume head. The second eruptive event is suggested to have been caused by a second plume head that is formed by the disconnected conduit, with the second plume head being predicted to reach the lithosphere at least 10 My following the arrival of the first plume head, which agrees generally with the observations regarding double flood basalts.

Sources & Further reading

1. Bercovici, David, and John Mahoney. "Double Flood Basalts and Plume Head Separation at the 660-Kilometer Discontinuity." Science 266, no. 5189 (November 25, 1994 1994): 1367-69.