Locality 93 Local bedlands in b2uded beds on SW fece of bluff above valley of Beaver Trap Cr. in about center SW 1/4, Sec 21, T. 15 N., R. 20 E, Thunder Butte quad, Ziebach Co., So. Dak. Fzcc drilled by 3-heeded gulley in centur S 1/2 SW 1/4, where b2se sections taken Section 1. Center EK 1/2 SE 1/4 SW 1/4 in first NE trending tributary to the SE gulley above confuence of the 3. Measuring from top of bentonite, variety Sec. 1, Loc 92 (1) 16.8 Dark gray clayey silt with blocky grct, zt b2se grading upward to a gray clay shzle very finely silty if at all, with szct czup furys, good shale begins about 5' from top (2) 2.3 Gray shale some silt lower dzc, zt top and b2se interlzm. vfq sznd in zones 0.3 and 0.4 thick, both highly charged with jzvosita. Shale has fine mottling as in some b2uded bad slect, szct piznt furys common. Section 2. Struts in NW gulley below head and czrrics NE to b2se bluff and up just SE highpoint. (1) 3.0 Beginning with jzvosite zone = (2) of sec #1 by tracing Gray clay shale, finely mottled with 0.5 jzvositic zone at base and 0.7 zt top cleable). Both on vfq snd interlock, fsilty. (2) 3.6 Chieflly shale, weth light bruish gray with szct piznt furys and liq. pertings, with interlocks of gray silt + some szcti pods vfq snd with concant jzvosite or Fe stain - these concent in upper 0.6 for most part. 29