Pg. 4 (table 1); App., p. A4-2 to A4-5. Hersey Member of Pierce Formation. (Follows the informal usage of R.W. Baker, 1984, Wisconsin Geol. Nat. Hist. Survey Gdbk, no. 11.) Is the lower member of Pierce Formation (new) in western Wisconsin. Consists of yellowish-brown to dark-gray, structureless, calcareous till and associated sand and gravel. Thickness 1 to 55 m. Basal contact is unknown except where it overlies Paleozoic bedrock. Underlies Kinnickinnic Member (new) of the Pierce, contact is gradational; or underlies River Falls Formation (new), contact is sharp. Is the surface unit in Buffalo, Dunn, Pepin, and Pierce Counties. Age is Pleistocene (pre-Illinoian).
Type section (=Pierce Formation type section): on west side of abandoned gravel pit, 200 m north of Highway 12, and about 0.6 mi (1 km) southwest of Hersey, in SW/4 SE/4 sec. 29, T. 29 N., R. 15 W., [approx. 44 deg. 57 min. 36 sec. N., Long. 92 deg. 13 min. 30 sec. W.], Wilson 7.5-min quadrangle, eastern St. Croix Co., western WI.
Named from Hersey; name credited to Robert W. Baker.
Reference section: exposure in Chicago and Northwestern RR cut, in town of Woodville, in SE/4 NW/4 NW/4 sec. 35, T. 29 N., R. 16 W., [approx. Lat. 44 deg. 57 min. 26 sec. N., Long. 92 deg. 17 min. 43 sec. W.], Baldwin East 7.5-min quadrangle, St. Croix Co., western WI.
[Additional locality information from Syverson and others, 2011, Wisconsin lexicon of Pleistocene units, Wisconsin Geol. Nat. Hist. Survey Tech. Rpt., no. 1; supplemented from USGS historical topographic map collection TopoView and Wisconsin Highways www.wisconsinhighways.org, accessed on June 9, 2018.]
[Misprint (p. A4-2). Abandoned gravel pit is in SW/4 SE/4 sec. 29, not SW/4 SE/4 SE/4. See Syverson and others, 2011, Wisconsin Geol. Nat. Hist. Survey Tech. Rpt., no. 1, p. 18 (fig. 7).]

Source: Publication; US geologic names lexicon (USGS Bull. 1565, p. 129).

[Not synopsized to date. Lithology, thickness, distinguishing characteristics, contacts, sections, areal extent, age, correlations discussed.]
Pg. 4 (fig. 2), 7 (fig. 3), 8, 18, 23-25. Hersey Member of Pierce Formation.

Source: NA