The bedrock geology of the 7.5-minute Worcester South quadrangle, Massachusetts, consists of deformed Neoproterozoic to Paleozoic crystalline metamorphic and intrusive igneous rocks in three fault-bounded terranes (zones), including the Avalon, Nashoba
Walsh, Gregory J. gwalsh@usgs.gov,Merschat, Arthur J. amerschat@usgs.gov. Bedrock geologic map of the Worcester South quadrangle, Worcester County, Massachusetts. 2015-01-01.