Van East group (new). Briefly summarized in reports by W.C. Hayes, p. 8 (strat. column), 81, 82, 83 (table 1), this volume. New names are credited to Tolman and Robertson (in prep.) [1969, Missouri Div. Geol. Survey Water Res. Rpt. Inv., no. 44 (Contrib. to Precambrian Geol., no. 1)]. Felsites of St. Francois Mountain divided into two groups, Middlebrook, older, and Van East, younger. Rocks of Van East dominantly rhyolite. Tuff present above many flows that have been assigned to Middlebrook and separates it from younger flows of Van East group. Includes French Mills felsite, Annapolis rhyolite, Stouts Creek rhyolite, and Hogan Mountain rhyolite (all new). Age is Precambrian.
Occurs in St. Francois Mountain area. Van East Mountain is in T. 33 N., R. 5 E., Madison Co., southeastern MO.

Source: Modified from US geologic names lexicon (USGS Bull. 1350, p. 794).

Van East group. Exposed in broad bands, generally surrounding outcrops of Middlebrook group, in Ironton-Fredericktown area, central part of St. Francois Mountains, southeastern Missouri. Includes 4 named units (in alphabetical order), Annapolis rhyolite, French Mills felsite, Hogan Mountain rhyolite, and Stouts Creek rhyolite, and unnamed units that don't have established stratigraphic relationships to other units. Is younger than Middlebrook group (the oldest of pre-batholithic rocks). Lies above Ketcherside tuff which separates the petrographically similar Middlebrook and Van East groups. Similarities between the two groups suggest a genetic relationship and their emplacement represents a relatively short interval of time. Age is Precambrian.
Named from exposures in vicinity of Van East Mountain, Madison Co., MO. (Type locality not designated.)
[GNU remark (February 21, 1990, USGS DDS-6; Denver GNULEX): Stratigraphic relationships of units of Van East not discussed in text; geologic map (plate 1) missing from library copy of report.]
[GNC remark (February 29, 2008): It appears †Van East group has not been applied these rocks since this publication. Considered abandoned.]

Source: Modified from GNU records (USGS DDS-6; Denver GNULEX).

Van East Group. Not used in western St. Francois Mountains, southeast Missouri (Midcontinent region). Nomenclature of Tolman and Robertson (1969) revised because of better understanding of regional structure and recognition of individual units consisting of ash-flow tuffs, air-fall tuffs, lava flows, and mixtures of these. Replaced with newly named formations (alphabetical): Buck Mountain Shut-ins Formation (High Top, Lindsey, and North Bell Mountains); Ironton Rhyolite (High Top, Lindsey, and North Bell Mountains); Lindsey Mountain Rhyolite (High Top and Lindsey Mountains); Russell Mountain Rhyolite (High Top and Lindsey Mountains).

Source: Modified from GNU records (USGS DDS-6; Denver GNULEX).