Australia: The Land Where Time Began

A biography of the Australian continent 

 LIPs - Paraná and Etendeka flood basalts

Gondwana continued to rift into the Early Cretaceous and this was associated with the eruption of a major CFBP, which is now separated by the South Atlantic, the Paraná Flood Basalts of South America and the smaller Etendeka Traps of Namibia (Harry & Sawyer, 1992; Jerram et al., 1999). An area of 1.5 million km² is covered by the twin provinces which may contain up to 2.35 million km³ of extrusive volcanics (Gladczenko et al., 1997). In the Paraná Province eruptions began at 133 ± 1 Ma (Renne et al., 1992), and ⁴⁰Ar-³⁹Ar ages from throughout the province indicate that there was little to no diachroneity to the eruptions, therefore it is believed the entire formed in 0.6 ± 1 Ma (Renne et al., 1996). The ages of these eruptions fall within the Valanginian and Hauterivian Stages (cf. Gradstein et al., 1994), an interval that is associated with low rates of extinction (Sepkoski, 1996). It has been suggested by some authors that the eruptions may be linked with a mass extinction event at the end-Jurassic (Rampino & Stothers, 1998; Courtillot, 1994, 1999). This interval is, however, considerably earlier and the so-called extinction that was first recognised in the 1992 compilation of Sepkoski is considered by Wignall to probably be an artefact (cf. Hallam & Wignall, 1997).

Sources & Further reading

Wignall, P. B. (2001). "Large igneous provinces and mass extinctions." Earth-Sci. Rev. 53: 1-33.