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Quadrangle Reports

Quadrangle Reports (QRs) are comprehensive peer reviewed geologic reports published by the State Geological and Natural History Survey of Connecticut which contain detailed maps for 7.5 minute quadrangle areas. They were originally published from 1951-1980, beginning again in 2012 with the publication of Hartford South as QR40.  Some QR maps are of an historic nature. Quadrangle maps were used as source material for later statewide compilations: Bedrock Geological Map of Connecticut (Rodgers, 1985), and the Quaternary Geologic Map of Connecticut and Long Island Sound (Stone et al, 2005). Nevertheless, the Quadrangle Report text is typically rich with observations and data not available elsewhere. 
Quadrangle Reports are available here as downloadable PDFs; some areas have GIS data [GeMS format].  The publication scale for most QR maps is 1:24,000; a few older maps were published at 1:31,680. Some maps contain layers which may be turned on and off using Adobe software.
Areas marked with an asterick (*) have more recent mapping available, either published or open file

Additional area maps may be available in geologic guidebooks or specialized publications.
Contact the Connecticut Geological Survey or consult the USGS National Geologic Map Database for further information.

Content last updated September 22, 2022