Australia: The Land Where Time Began

A biography of the Australian continent 

Siberian Traps Flood Basalts - Rapid Eruption at Permian-Triassic Boundary

The Siberian Traps are one of the most voluminous flood basalt provinces on Earth. Data obtained by laser heating ⁴⁰Ar/³⁹Ar indicate that the bulk of these basalts was erupted over a period of time that was extremely short, 900,000 ± 800,000 years, beginning at about 248 Ma with mean eruption rates of more than 1.3 million cu km per year, the authors¹ suggesting this is consistent with their origin being a mantle plume. Significant lithospheric rifting was not associated with this magmatism, therefore mantle lithospheric decompression that resulted from rifting was probably not the primary cause of the widespread melting. Initiation of the volcanism that produced the Siberian Traps coincided (within uncertainty) with a severe faunal mass extinction event at the Permian-Triassic boundary 249.4 ± 4 Ma, the authors¹ saying these data thus leave open the possibility of there being a genetic connection between the 2 events.

Sources & Further reading

1. RENNE, PAUL R., and ASISH R. BASU. "Rapid Eruption of the Siberian Traps Flood Basalts at the Permo-Triassic Boundary." Science 253, no. 5016 (July 12, 1991 1991): 176-79.