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#pangea — Public Fediverse posts

Live and recent posts from across the Fediverse tagged #pangea, aggregated by home.social.

  1. Now the more #riebeckite facies of the #Paleozoic #Quincy #Granite

    The Quincy granite was a prized architectural stone, most famously used in the #BunkerHill Monument in #Boston #Massachusetts. Current dating suggests it was intruded into #Avalonia before it glommed onto #Laurentia as #Laurasia and #Pangea were assembled. Today’s #photo set comes from a walk around the eponymous Bunker Hill Quarry. I’ll post more about the history later. Captions!
    #Fujifilm #XH1 #igneous #intrusive #NewEngland

  2. Quincy or #BlueHills #Porphyry #Granite
    An alkaline, nonorogenic granite intruded into #Avalonia in the #Silurian / #Ordovician as it cruised from peri-#Gondwana to #Laurentia, before assembling #Pangea in the #Acadian #Orogeny (#Devonian). It’s coarse, with the #phenocrysts of amphiboles(?) (possibly riebeckite?)…I’m no petrologist. From@the Eaton’s Pond conservation area@at the #Braintree #Quincy border. My photos.
    #geology #igneous #Massachusetts #Boston #NewEngland #Fujifilm #photo