This newly released United States Geological Survey Water Resources Investigations Report covers the lithogeochemistry (carbonate/ clastic content, metamorphic type, and igneous type) of bedrock of Connecticut, western Massachusetts, eastern Vermont, western New Hampshire, and small parts of Rhode Island, New York, and Quebec, Canada. The lithogeochemical rock units also are grouped into nine lithologic and physiographic provinces and three major regions: (1) western highlands and lowlands, (2) central lowlands, and (3) eastern highlands.