Sunday, March 29, 2015
Selenium is sulfur’s sober mate,
Not lost to vapor bubbles of the mind
In rock or water, should one saturate
They stay together, besties of a kind.
Se cannot be photosynthesized
To form selenate in anoxic seas
From fractionation, we hypothesize
an oxic whiff in late Archean breeze.
The isotopic signal is preserved
when anions are partially reduced.
Complete reduction, ratios are conserved
No atmospheric signal’d be produced.
But choose your sample wisely, and you’ll see
The right technique reveals its history