Welcome to Postcard Friendship Friday, hosted by Marie at the French Fractrice.
This postcard of the bedrock geology of CT came out rather pale, I'm afraid. And, the original is back in my office so I can't walk you through the details!!! I found a few more of these geological postcards buried deep in a drawer, so I have a few more to share with you.
I can tell you that most of the bedrock on the east and west of CT is metamorphic, though of different types and ages, therefore the different colors on the map.
The yellow area with red squiggles in it is the Hartford Basin. This area is interesting for several reasons. According to Gil Hanson, a geologist at SUNY Stony Brook, "The Hartford Basin is one of the many rift basins along the east coast of North America that formed during the early stages of rifting of Pangea during the Triassic and Jurassic. The rifting of Pangea eventually led to the formation of the Atlantic Ocean. The Hartford Basin contains a thick sequence of stream and lake sediments and basaltic sills and lava flows all of which are well exposed."
(To see an animation of the breakup of Pangea, go to this website by Chris Scotese. Move your mouse over the animation on that page, click and hold the left mouse button, and slide your mouse sideways. Cool!)
The red parts are intruded sills and lava flows, now making ridges and hills running down this valley.
The stream and lake sediments in some cases preserved dinosaur footprints. These can be seen at Dinosaur State Park!
Here is something else I found out through Google (how did we live without this?). The Brownstone buildings of NYC and Boston are made from the Portland formation, quarried from this area of Connecticut. According to the website on this formation, "The prevalence of Portland sandstone for construction during this era lead to the term "brownstone" being synonymous with "rowhouse" in the northeastern US."
Would you like a copy of the Generalized Bedrock Geologic Map of Connecticut, in a 8.5 by 11 inch size? Only 25 cents! You may purchase it through the on-line store of the Connecticut Department of Environmental Protection, which also includes the Connecticut Geological and Natural History Survey.
Viridian
And please remember the plight of the people of Haiti. That EQ epicenter was very close to Port-au-Prince, the major population center, and Haiti building codes, such as they are, cannot be compared to those of California. This EQ is as big as the Loma Prieta or Northridge EQ's, but much more devastating.
11 comments:
I'm glad to see another geology postcard; I love these.
Where do these postcards come from, Viridian. They are so fantastic!
I truly enjoy stopping by for your geological discussions!
Nice to see a card for Connecticut. I have some lovely "corncob" quartz crystals from that state but I can't recall the locality. Happy PFF!
Howdy
Happy PFF to you .
Thank you for all the awesome links for the curious person like Moi :)
Thank you also for the reminder of the people of Haiti.
It is all so very sad.
A great post today.
Have a wonderful weekend .
Happy Trails
That was very educational. Happy PFF.
i always find your geological maps quite beautiful, almost like abstract paintings...and thank you for mentioning haiti at a time when we're all too aware of the terrible tricks geology can play!
I don't know whether it's your geology postcards that have made me more aware, but there seem to have been so many earthquakes recently! Of course the one in Haiti has been by far the worst but there have been many, many others.
Your geological postcards are very interesting. I learn something every week! Thanks for sharing PFF!
I have a friend who just bought a brownstone in Boston! I can't wait to floor her with this tidbit of history!
Who knew? I think in another life, I could have been a geologist... or at least a geological postcard collector. Happy PFF, Viridian!
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