Four years ago, I heard of chloroplasts, which spiced the Boring Billion 1342 Mya. We already had the water of course - but also molybdenum, which must come from the outer solar system. Our moly' was claimed from Theia. I couldn't square these data; so I mooted the moly' was buried under the surface, much-later ejected by volcano to feed the future plants.
Rutgers today is talking late-accretion, with moly' and also ruthenium - although you need into the paper for that. Rutgers' summary makes little sense to me.
Best I can tell from the paper: the moly' seems linked with the last noncarbon chondrites. This is tagged "10 to 20 wt%" by time, such a chunk as would precede the Theia merger. After Theia was buried, when our Moon formed (less far) above us: comes the "0.5 to 2 wt%... veneer". This has the ruthenium our miners can get to. Apparently ruthenium is so ironloving ("siderophile") that preTheia ruthenium would have just merged with molten iron, to sink to the lower mantle.
A bit surprising to me, the preTheia moly' seems to come from carbonaceous chondrites... which I guess it would. The later veneer is heavily stony, by contrast. They're mooting that by then we already had that asteroid-belt barrier. Stones are mostly what was left, all the way out to Mars and Vesta (both very stony themselves). Here's the last para':
The finding of an NC-dominated accretion during the late-stage of Earth’s accretion implies that the putative Moon-forming giant impactor was NC in nature and presumptively originated from materials formed in the inner Solar System. If the interpretation that CC materials originated in the wetter outer portion of the Solar nebula is correct, then these results suggest that late-stage accretion may not have provided the bulk of Earth’s water.
So I guess the water was always underneath us and has simply bubbled up.
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