#mincup25 — Public Fediverse posts

This is one of the dykes found near Ayer's Cliff, just SE of Magog, Quebec. It's a set of three dykes, one of which has the deep-derived xenoliths. That one dyke (not photogenic) has weathered much faster, perhaps due to a higher carbonate content.
#kyanite #MinCup25 #Quebec #Xenolith #Grenville #Appalachians

On rocks, from Mineral Cup’s admin, @mikamckinnon
She writes:
#Hematite is a key mineral in banded iron formations. And BIFs are my BFFs

Very well done! BIFs make their appearance around minute five.

https://www.ted.com/talks/mika_mckinnon_do_you_have_a_rock

Thanks for the heads up
@vickyveritas
@vickyveritas.bsky.social

#MinCup25 #BandedIronFormation #GreatOxidationEvent #Stromatolites #EarthHistory #EarthSystemScience

Today, molybdenum is one of the most common trace elements in the ocean due to oxidative weathering of #Molybdenite. But in the Archean the oceans were reducing, and molybdenum was scarce.

Other nitrogenases evolved to use other transition elements, but Mo-nitrogenase was first, and best.

Molybdenite enables the Earth's biosphere!

#MinCup25 #NitrogenFixation #Nitrogenase #Archean #GreatOxidationEvent #OreCup #OreCup25