800 million years ago, the Boring Billion ended as our Moon broke its nineteen-hour tidal resonance and started its gradual march outward. There was nothing naturally geological going on down here; supercontinent Rodinia had formed 100My before (supercontinents are even more dead and boring) and would last another 50My. Perhaps we might have been pushed from outside.
Bottke et al. say our moon got a surge of craters (including Copernicus); Earth too should have had still more. Keep in mind that Bottke like Loeb has a history of meddling in Chicxulub and getting it wrong, although Bottke hasn't since gone as totally stupid as far as I know.
A lot of this relies on simulation. The craters match if a swarm of loose asteroids had reached the 3:1 Jupiter resonance all of a sudden. A big impact would push fragments into 3:1J (they call it "J3:1"). So, a bunch of impacts immediately; then the Yarkovsky Effect kicks in for more of the surviving rubble, heating and outgassing the volatiles to 3:1J over the next 150My.
That resonant region, noted on this blog, includes 495 Eulalia and 142 Polana. Eulalia is currently 1:2 resonant with Mars; Polana more like that 3:1J. Polana, we know, is tossing stuff like Bennu at us. But the Bottke Boys be pointing at Eulalia because they note it broke up ... 800 Mya. Polana has probably not been where it is for long.
They also blame these inner-crossing rocks for a surge of volcanism over then-dead-already Mars. And with "shifts in the biosphere" here. At that time nonplant life here was still stolonic. Wiki points to a "Choanozoa" postfungal but not yet animal.
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