Interesting article in today's Indie: https://www.independent.co.uk/news/...ty-earth-climate-change-co2-mit-a8822711.html MIT seems to have published some research correlating the onset of various ice ages with the upthrust of oceanic crust that often accompanies the closure of oceans. The idea seems to be that the chemical composition of oceanic crust includes rocks that absorb CO2 from the atmosphere. I vaguely recall the old distinction between "sial" and "sima", viz. Si/Al vs. Si/Mg that distinguishes the two. However I don't have any detailed information on the mineralogy of these rocks. I can certainly see that Mg has a propensity to form carbonates, but what the thermodynamics is of Mg carbonates vs. various complex Mg silicates I do not know. Does anyone have access to the paper? I'd be interested to read it.