I remember reporting on this in my blog, but there are no blog entries before 2005. I don't remember if I had some kind of problem that caused me to lose previous entries, or if Blogger purges blog entries older after a certain length of time, or maybe when a certain number of posts or storage space is exceeded? If so, too bad. One of the purposes of my blog is to retain info I am interested in keeping so I can find it later.
I wasn't able to find out if Ms. Abbott suggested a mechanism for this correlation at the time of this research. Other people suggested that some asteroids were powerful enough to crash thru the earth's mantle and create a hole for volcanoes to erupt thru, but I couldn't find out what Ms. Abbott thought.
13 December 2002 by Kate Ravilious
Large meteorite impacts may not just throw up huge dust clouds but also punch right through the Earth's crust, triggering gigantic volcanic eruptions.
The idea is controversial, but evidence is mounting that the Earth's geology has largely been driven by such events. This would also explain why our planet has so few impact crater remnants.
Counting the number of asteroids we see in the sky suggests that over the past 250 million years, Earth should have been hit around 440 times by asteroids larger than one kilometre across. But scientists have found only 38 large impact craters from this period.
Dallas Abbott from Columbia University and her colleague Ann Isley from the State University of New York studied the timing of these 38 impacts and found that they correlate strongly with eruptions of "mantle-plume" volcanoes during the same period.
Most volcanoes come from small amounts of the Earth's upper mantle boiling over, but mantle-plume volcanoes happen when hot rock from deep within the Earth's mantle shoots straight up through the Earth's crust. The timing suggests that these volcanoes are related to asteroid impacts, Abbott and Isley report in Earth and Planetary Science Letters (vol 205, p 53).
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