Locality 92. Exposures on both sides SE trending nose of high bluff, at confluence of Thunder Butte Cr. and Beaver Trap Cr., lying chiefly in NW 1/4, NW 1/4, SE 1/4, sec. 29, T. 15 N., R. 20 E, Thunder Butte quad., Ziebach Co., So. Dzk. Extends into W side NE 1/4 NW 1/4 SE 1/4. About 80 ft of lower Fox Hills up to bentonite at top and including remnant 15 foot fossilif. zone of T.L. member. Section 1. On SW-facing bluff above Thunder Butte Creek. Measuring up from top of beveren ls. conc. layer (local designation layer A). - locally these concs hug up to 2' thick 4' long D., w/ thin yellow-white -crusty, zvc grey silty ls. inside, brittle. 1) 17.5 A 798 Sandy clayey silt with blobs vfg sand + silt, massive, gray with yellow to orange Fe sta. some on freshly weathering light brown green. Arbitrary breaks this unit to record first fossilif. concs found in place = spec. 92(1)a and 92(1)b A799. A920 Specs 92(1)c found 1.0 above the others. 2) 14.0 Sandy, clayey silt zs below, somewhat more clayey in lower 8 ft, clayey zcvc dtr gray Scattered ls cons, some beveren, z few fossilif, up to 1.0 from top. Big spheroid loosely suzle 1.0+ from base A921 Spec. 92(2)a 1.5+ form top 3) 0.4) Devostic clayey silt with bright yellow-orange band on top. 4) 0.4 Bentonite, yellow green, finely silty 5) 5.5 -> ? Gray clayey silt w/ th. brn lower 0.8 bentonitic. Unit is zccly unigum