Ordovician stratigraphy of central Vermont

Bedrock Geology and Asbestos Deposits of the Upper Missisquoi Valley and Vicinity, Vermont

“…The Shaw Mountain formation (Currier and Jahns, 1941, p. 1496-1501 crops out at and east of the eastern border of the area of the present investigation (Doll, 1951, p. 18-20, pi. 1).…”

“…The basal part of the Cram Hill as used by Doll is the Umbrella Hill formation, but the principal and remaining portion is chiefly phylliteslate. This phyllite-slate is a facies of the Moretown formation that in central Vermont is separated along strike from the type Cram Hill formation (Currier and Jahns, 1941, p. 1493-1496 by areas of granulite and quartzite that contain no phyllite or slate (Cady, 1956). Because of the intervening granulite and quartzite, identification of the phyllite-slate as the Cram Hill is not clear.…”

“…The Northfield slate (Currier and Jahns, 1941, p. 1501-1506) is a quartz-sericite slate (table 2, column 14) with widely spaced interbeds of siltstone and silty crystalline limestone that are a few inches thick. Minor constituents of the slate include carbon, ilmenite, porphyroblastic ankerite, and tourmaline.…”

Bedrock geologic map of the Saxtons River 7.5' x 15' quadrangle, Windham and Windsor counties, Vermont

“…The name Cram Hill (Currier and Jahns, 1941) originally was applied to greenish-gray to black phyllite that contains minor beds of siliceous volcanic breccias, soda rhyolite, and basalt or basaltic andesite. A basal quartzite mapped as the Harlow Bridge Quartzite Member of the Missisquoi Formation provided a useful marker to distinguish greenish phyllites of the Moretown (below) from identical rocks of the Cram Hill (above) (Currier and Jahns, 1941, p. 1487-1512.…”

“…A basal quartzite mapped as the Harlow Bridge Quartzite Member of the Missisquoi Formation provided a useful marker to distinguish greenish phyllites of the Moretown (below) from identical rocks of the Cram Hill (above) (Currier and Jahns, 1941, p. 1487-1512. The Harlow Bridge Quartzite Member at its type locality is a pinstriped biotite-chlorite-muscoviteplagioclase-quartz quartzite that is identical to the pinstriped granofels member (Oml) of the Moretown Formation of southern Vermont and western Massachusetts.…”