SECTION 8225 280 m E., 1380 m N. of SW corner sec. 1, T. 20 N., R. 35 E., Garfield County, Montana. Unit Elevation at Base (m) Thickness (m) Tullock Formation: 8.9 Top of section Siltstone, mudstone: in alternating yellow and orange interbeds, mudstone with limonitic concretionary ledges, typical of Lower Tullock. 1.48 6.43 Shale: silty, dark grey, fissile bentonitic, carbonaceous, with mollusk shells. Weathers brownish grey. .62 6 5.8 5 5.35 Mudstone: chippy, medium greenish grey with limonite staining on joints. .45 Shale: fissile, slightly silty, light yellow green, with horizontal roots, rhizomes, and rare leaves of Nelumbium montanum. Upper 0.45 m a fissile mudstone with roots. 3 mm lignite stringer at 4.7 m. .75 4 4.6 3 4.54 Lignite .06 Hell Creek Formation Paleosol sequence: 4.5 Siltstone: highly carbonaceous. Clay: highly disrupted, silty, vertical and horizontal roots. 0.1 m above base become full of disseminated carbon, steel blue grey, with roots and rare clay blebs. 4.2 3.9 Mudstone with carbonaceous blebs. Sandstone: very fine grained, silty at base, penetrated by roots, weathers light greenish yellow with orange limonite modules. .84 3.7 Mudstone: massive, greenish grey, limonite stained, with rare plant fragments, and man- ganese coatings on joints. Gradual transition to greenish yellow above 2.4. Upper 0.4 m with vertical roots and limonite yellow staining. 3.7 0 Base of section ;