CTgeo
The Influence of Geology on the Connecticut Landscape
Photo Essay by Ralph Lewis, Connecticut State Geologist

The following is a series of digitized slides of Connecticut landscapes and geology, with photos and commentary by Ralph Lewis.  We eventually will have 66 images with text posted here, which will take some time to compile and annotate.   Please check back until the complete set is posted. 

To see a larger image of each slide, just click on it.  Close the slide image to return to the page.

Introduction. Slides 1-9 depict features of the mid-Connecticut landscape
RalphsSlide1.jpg (57698 bytes) The Connecticut landscape is closely related to its geology -- rocks, faults, sediments, and history of geological events.  The surface of our state can be vividly shown by synthetic relief maps such as this, which includes the rarely seen bottom of Long Island Sound. 
RalphsSlide2.jpg (55622 bytes) Connecticut has a natural division into three parts: the western highlands, central valley, and eastern highlands.  The highlands are also called uplands.
RalphsSlide3.jpg (32419 bytes) A low and slow airplane is an ideal platform for seeing Connecticut landforms.  Looking south down the central valley toward Hartford, we can see how flat the land is along the Connecticut River.  This is due to a combination of relatively recent floodplain river deposits, and also somewhat older Lake Hitchcock sediments that fill much of the valley north of Middletown.
RalphsSlide4.jpg (43291 bytes) At Middletown, the Connecticut River takes a turn to the east and runs through the harder rocks of the eastern uplands to Long Island Sound.
RalphsSlide8.jpg (49982 bytes) Looking to the north in the central valley, a series of ridges can be seen to have a steep western face but a gentle slopes toward the east.  These ridges are mainly basalt, also called traprock -- the lavas of great Mesozoic volcanic eruptions.  They are surrounded by softer sedimentary rocks, mainly sandstones.
RalphsSlide5.jpg (39633 bytes) The eastern uplands have rolling hills that are held up by relatively hard metamorphic rocks.
RalphsSlide6.jpg (21060 bytes) Looking westward, we also see a distinct ridge from the central valley into the western uplands.
RalphsSlide7.jpg (57100 bytes) Looking to the east from the western highlands, we can see the north-south ridges in the central valley.
RalphsSlide9.jpg (42336 bytes) Even as far as Long Island Sound, we see points made from the central ridges.
The next series of slides illustrate how plate tectonics created Connecticut.