Geologists, using computer models, have reconstructed the size and impact velocity of a giant asteroid that hit the Earth approximately 3.26 billion years ago.

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Geologists, using computer models, have reconstructed the size and impact velocity of a giant asteroid that hit the Earth approximately 3.26 billion years ago.

This is a fascinating result, but it is very important to recognize its very large uncertainties. The article for example says almost nothing about how these conclusions were reached, except for this one paragraph:

Lowe, who discovered telltale rock formations in the Barberton greenstone a decade ago, thought their structure smacked of an asteroid impact. The new research models for the first time how big the asteroid was and the effect it had on the planet, including the possible initiation of a more modern plate tectonic system that is seen in the region, according to Lowe. [emphasis mine]

I have highlighted that one word because it reveals a great deal. What they did was to create a computer model of the data they had, which was merely very unusual geology spread over a certain region called the Barberton Greenstone Belt. Note also that this region is not where the impact occurred. “The study’s co-authors think the asteroid hit the Earth thousands of kilometers away from the Barberton Greenstone Belt, although they can’t pinpoint the exact location.”



  • joe

    Models, you mean like the ones the climate science people use to predict the weather in 5, 10, 20 years from now, that kind of model? I think that there are just too many pieces to the puzzle to come to any kind of meaningful conclusion. for scale, 300 miles is approx. from the bottom of Michigan to the Big Mac bridge, that’s a pretty big hole to put in the mantle.

  • Edward

    The good news is that geologists created their models based upon small-scale tests and comparing these tests with observed large-scale craters.

    Climatologists seem to have created their models based upon untested hypotheses that small increases in CO2 levels in the atmosphere result in large increases in atmospheric temperatures, and put insufficient effort into alternate possibilities for temperature change or natural feedback loops.

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