Margaret M. Loos
We have now traveled around our harbor in class and in fact. In order to see the area in perspective we have incorporated a great deal of geology for background. However, some aspects of the geology of the whole state of Connecticut are fascinating and surprising. It’s funny but one of the observations that young students make when confronted with a map of the world is that Africa looks as if it will fit like a puzzle piece in the indentations of the North and South America. Geologists have presented a theory that we call Wegener’s Pangea to explain this and other noticeable relationships. Wegener proposed that a supercontinent existed that probably included all of the continental masses which exist today.
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When it divided into several masses that part that subsequently made up most of America, we now refer to as Proto-America. It was bounded to the East by an ocean, not the Atlantic, but a different body of water, the Iapetos, East of Proto-America a small continental mass, Avalonia existed. If we can imagine these all being sandwiched into each other we would find the materials of Proto-America in our Westland Highland section. A great period of geologic change “eliminated Iapetos from New England, transforming what was left of it into continent and thus soddering the small continental mass of Avalonia onto the mainland of North America.”
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A strip of volcanic islands seems to also have been incorporated into the coastline. A new bedrock map of the state is being prepared and the chief classifications designated are Proto-American, Newark (another name for our Lowlands), Oceanic (Iapeton) and Avalonian.
(figure available in print form)
PANGEA 200 Million Years Ago
(figure available in print form)
The World Today
It is important to realize that geology has ongoing processes roughly divided into constructive and destructive. Those that build up the crust and those that are wearing it away. Connecticut is not in a stage of uplift. It has had active periods of mountain building in the past but now erosion processes have dominated for a long period creating
peneplain
, an almost flat lowland, “the nearest thing to complete victory for the leveling processes.
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The simplest prediction to be made on the basis of the geology of our harbor might be that it will continue to undergo erosion and submergence. We’ve had some light earthquake activity in this region in the last ten years, but conditions for crustal uplift and mountain building are not obvious, but I’m the teacher who told her students that volcanic eruptions didn’t seem to occur much in the continental United States three days before Mt. St. Helens blew its top.