Geology of Connecticut
Connecticut is a US state. It is in the north-eastern side of the country. As part of the New England region, Connecticut has undergone much geologic change. It has been shaped by plate tectonics, volcanism, and glacial activity.
Appalachian Mountains
changeDuring the early Triassic Era, the super-continent Pangea was formed as the Iapetus Ocean closed up and the proto-North American continent collided with Avalonia (modern day Africa). This caused great uplift and the creation of the Appalachian Mountains. The erosion of the Appalachian Mountains now exposes and lifts up metamorphic rocks that used to be very deep in the Earth's.
Eastern Border Fault
changeAbout 200 million years after this collision and the formation of Pangea, during the middle of the Mesozoic Era, the Atlantic Ocean floor started spreading. This caused a lot of stress. This caused a geologic fault. Connecticut's famous Eastern Border Fault was created. As a result, the land west of this fault was downset, creating a rift valley and causing the land to tilt an average of 15 to 25 degrees. The fault is currently inactive. The formation of this basin eventually refilled with soft fluvial and alluvial sediments.
Ice Age
changeDuring Ice Ages, glacial activity shaped much of New England's landscape, eroding mountains, leaving glacial till scattered everywhere, and forming glacial lakes. At its greatest extent, one of these glaciers leaves behind a moraine which became Long Island.
One of the biggest glacial lakes of the time was Glacial Lake Hitchcock. It formed when the Laurentide ice sheet retreated and glacial meltwater began to accumulate at the glacier’s terminal moraine in Rocky Hill, Connecticut and back up into the Connecticut River. The glacial lake left behind a soft, varved landscape, gathering silt and sand in the summertime due to the influx of glacial meltwater and clay in the wintertime as the lake froze until it was later drained.
River Valley
changeRiver Valley has a soft surface. It is also high in nutrients and host the majority of Connecticut's farmland soils. The land on either side of the Connecticut River Valley is less suitable for farmlands. The eastern section holds the shallow Proto-North American Terrane while the western section contains the Iapetos and Avalonian Terranes. These places still holds remnants of glacial till and lack the soft fluvial sediments so prominent in the Connecticut River Valley region.
