Impact Cratering and Flood Volcanism

An interesting paper about the relationship between impact 
cratering and flood volcanism is:

Sherlock, S. C., S. P. Kelley, L.  Glazovskaya, and I. U. Peate, 
2009, The significance of the contemporaneous Logoisk impact 
structure (Belarus) and Afro-Arabian flood volcanism.
Journal of the Geological Society. vol. 166, no. 1, pp. 5-8.
http://jgs.lyellcollection.org/content/166/1/5.abstract

They concluded:

"It is apparent that a 17 km diameter impact crater, peak
eruption in a large igneous province, and one of a series of
Oligocene sudden climate cooling events all occurred within
1 Ma and probably within less than 0.5 Ma."

Given the frequency of both events and length of periods 
of flood volcanism, they concluded "...that contemporaneity 
of impacts and flood volcanism was the norm..." during
Earth prehistory. They do not argue that there is any cause 
and effect relationship between large extraterrestrial 
impacts and flood volcanism. They are only concerned
with the environmental consequences of the occurrence 
of a large extraterrestrial  impact during a period of 
flood volcanism.

Yours,

Paul H.