Earth’s nitrogen-rich atmosphere linked to plate tectonics

For all you evolution fans out there, here’s is another interesting piece of the puzzle:

Earth’s nitrogen-rich atmosphere linked to plate tectonics Reactions deep in the crust liberate nitrogen, which volcanoes can then release. by Simon Redfern Oct 29 2014,
... As oceanic crust is subducted (that is, dragged down beneath continental crust) into the depths of the Earth by the cycle of plate tectonics, it releases “volatile" chemicals into the rock above. These volatile chemicals contain nitrogen—and its fate could be to either end up locked in minerals or be released as gas into the atmosphere. The chemical composition of the overlying rocks decides the fate of the volatiles. Nitrogen deep in the Earth’s crust will tend to form ammonium ions (NH4+), which get incorporated into solid silicate minerals easily. Silicate minerals are among the most abundant kind of minerals in Earth’s crust, so this is a very favorable reaction and is presumed to have occurred to much of the nitrogen on Earth and pretty much all of the nitrogen on Venus and Mars. But when those silicate minerals react under certain conditions, such as in the presence of oxygen or oxygen-containing compounds, the ammonium molecules break down to a mixture of water (H2O) and nitrogen (N2). The latter then finds its way to the surface and the atmosphere through volcanic vents. Mars and Venus have no plate tectonics and relatively little nitrogen. The nitrogen-rich atmosphere that helped make Earth a home for life appears to have its origin in the fact that the planet itself is a geologically active beast. ...
Folds within folds of cumulative harmonic complexity cascading down the river of time. What an incredible show it's been. :cheese: