Pg. 119-121, 123-124, pl. 1 (geol. map); J.B. Hadley and others, 1938, Geol. map and structure sections of New Hampshire portion of Mt. Cube quadrangle, New Hampshire Hwy. Dept., scale 1:62,500; C.A. Chapman and others, 1938, Geol. map and structure sections of Mascoma quadrangle, New Hampshire, scale 1:62,500.
Post Pond volcanic member of Orfordville formation. Consists of green chlorite-sericite schist in low grade metamorphic zone of Orfordville formation and amphibolite, amphibole gneiss, calcareous amphibole gneiss, fine-grained biotite gneiss, and gray quartz-mica schist in middle grade zone. Occurs near base of formation below Hardy Hill quartzite member (new). Thickness 2,000 to 4,000 feet. Age is Middle Ordovician(?).
Named from outcrops in vicinity of Post Pond, Lyme Twp., Mt. Cube 15-min quadrangle, Grafton Co., northwestern NH. Outcrop belt extends southwestward into VT.

Source: US geologic names lexicon (USGS Bull. 1200, p. 3111-3112).

Pls. 1, 2 (geol. maps). Post Pond volcanics. Mapped as separate unit underlying the Albee formation and overlying the Orfordville formation. Map legends show Upper(?) Ordovician age.

Source: US geologic names lexicon (USGS Bull. 1200, p. 3111-3112).

Pg. 108 (fig. 2), 113, 114-116, pl. 1 (geol. map). Post Pond volcanic member of Orfordville formation. West of Ammonoosuc thrust, consists chiefly of chlorite schist; east of thrust, consists chiefly of hornblende schist, amphibolite, and feldspathic schist. Thickness estimated to be 3,500 to 4,000 feet. Stratigraphic position revised; lies in upper part of formation above the Hardy Hill quartzite member. Stratigraphic revision of the Orfordville implies that the Post Pond and Sunday Mountain volcanic members are essentially equivalent; latter is not separately mapped. [On p. 108 (fig. 2) age is considered Middle Ordovician(?); on pl. 1 (geol. map) age is considered Ordovician(?).]

Source: Publication; US geologic names lexicon (USGS Bull. 1200, p. 3111-3112).