Pg. 4 (table 1); App., p. A1-3 to A1-4. Allens Grove Member of the Walworth Formation. (Name credited to Carl Fricke, 1976, Univ. Wisconsin MS thesis, and David M. Mickelson.) Occurs in southern Wisconsin and northern Illinois. Consists of light-brown to yellowish-brown sandy pebbly till and associated deposits. Thickness up to 3.9 m. Overlies Foxhollow Member of Walworth Formation (both new); contact is sharp. Underlies Clinton Member (new) of Walworth; contact is sharp to gradational. Equivalent to Argyle Till Member of Winnebago Formation in Illinois. Interpreted as glacial till deposited by ice from Lake Michigan basin. Age is Pleistocene (early Wisconsinan or older; before 40,000 yr B.P.).
Type section: base of west wall of borrow pit, 0.5 mi (0.8 km) east of Allens Grove, about 2.5 mi (4 km) west of Capron Ridge and just north of old Highway 15, in NW/4 SE/4 SW/4 sec. 32, T. 2 N., R. 15 E., [approx. Lat. 42 deg. 34 min. 59 sec. N., Long. 88 deg. 44 min. 59 sec. W.], western edge Sharon 7.5-min quadrangle, Walworth Co., southeastern 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, accessed on June 9, 2018.]

Source: Publication; US geologic names lexicon (USGS Bull. 1565, p. 10).

[Not synopsized to date. Lithology, thickness, distinguishing characteristics, contacts, sections, areal extent, age, correlations discussed.]
Pg. 4 (fig. 2), 7 (fig. 3), 8, 47-48. Allens Grove Member of Walworth Formation. (=Argyle Member of Winnebago Formation of Illinois; Argyle not used by WI Geol. Survey.)

Source: NA