Australia: The Land Where Time Began

A biography of the Australian continent 

Deccan Volcanism State Shift at Cretaceous-Palaeogene Boundary Possibly Impact Induced

Renne et al. suggest that at the close of the Cretaceous leading candidates for the cause of the mass extinction event are impact of a bolide and flood volcanism. It is indicated by high precision ⁴⁰Ar/³⁹Ar data that there may be genetic relationship between these 2 mechanisms, with the result that neither can be considered in isolation. The magmatic system of the existing Deccan Traps underwent a state shift approximately coincident with the impact at Chicxulub and the mass extinction event at the close of the Cretaceous, and following this event ~70 % of the total volume of the Traps was extruded in more massive, more episodic eruptions. Within ~50,000 years of the impact the new regime was initiated, which is consistent with the transient effects of seismic energy that is induced by an impact. Recovery of marine ecosystems is suggested by Renne et al. to have probably been suppressed until after the waning of the accelerated volcanism.

Sources & Further reading

1. Renne, P. R., C. J. Sprain, M. A. Richards, S. Self, L. Vanderkluysen and K. Pande (2015). "State shift in Deccan volcanism at the Cretaceous-Paleogene boundary, possibly induced by impact." Science 350(6256): 76-78.