The Weymouth Formation is a geologic formation in Massachusetts. It preserves fossils dating back to the Cambrian period. It was originally named for the Cambrian strata in the âÂÂBoston Basinâ by Amadeus Grabau and Henry T. Burr, at Nahant and Mill Cove. Ed Landing correlated the Hoppin Formation with the Weymouth Formation and thus abandoned use of that name.