Chris White · @Ceedave
103 followers · 119 posts · Server sciencemastodon.com
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
#bluehills #porphyry #granite #avalonia #silurian #Ordovician #gondwana #laurentia #pangea #acadian #orogeny #devonian #phenocrysts #braintree #quincy #geology #igneous #massachusetts #boston #newengland #fujifilm #photo