54. Chalk, weathered grayish orange to pale grayish orange, lichen-covered, moderately hard, with numerous burrow structures; FOSSILS - Inoceramus platinus, Inoceramus grandis, Ostrea congesta . . . . . . . . . . . . 0.6 53. Shaly chalk, olive-gray weathering grayish yellow to pale yellowish orange, soft, speckled, numerous powdery gypsum seams, limonite nodules at several levels with several zones of more resistant, massive ledge- forming chalk; harder beds are yellowish gray weathering grayish orange, laminated; unit very fossiliferous; FOSSILS - Inoceramus platinus, Ino- ceramus grandis, Ostrea congesta, burrow structures . . . . . . . . . 12.8 52. Chalk, medium-light-gray and shaly near base, yellowish-gray in upper part, weathering grayish orange, relatively hard, with sparse limonite nodules; FOSSILS - Inoceramus grandis, Inoceramus platinus?, Ostrea congesta . . . . . . . . . . . . . . . . . . . . . . . . . . 1.9 51. Bentonite and gypsum; bentonite is dark yellowish orange, gypsum powdery 0.02 50. Shaly chalk, dark-yellowish-brown to light-olive-gray, soft, laminated; FOSSILS - Inoceramus grandis, Inoceramus platinus?, Ostrea congesta . . 0.42 49. Bentonite, dark-yellowish-orange, slightly silty, selenite at top . . . 0.06 48. Chalk, weathered grayish orange, weathers flaky . . . . . . . . . . . . 0.17 47. Bentonite and gypsum; unit is predominantly white powdery gypsum . . . 0.05 46. Chalk, olive-gray weathering grayish yellow, grayish orange and dark yellowish orange, except for one hard bed that weathers shaly, especially at base; shaly part riddled with irregular-shaped chalk-filled burrow structures; partly limonitized marcasite nodules lie near top of unit; FOSSILS - Inoceramus grandis, Inoceramus platinus?, Ostrea congesta . . 2.4 45. Shaly chalk and chalk, pale-olive-gray to moderate-yellowish-brown, slope forming, nonresistant, riddled with irregular chalk-filled burrow structures in zone lying 0.8 foot below top; many smaller cylindrical burrow structures in chalk in lower half; pelecypod shells fragmentary; FOSSILS - Inoceramus sp.. . . . . . . . . . . . . . . . . . . . . 2.9 Thickness of exposed part of Smoky Hill Chalk Member 53.7 Fort Hays Limestone Member 44. Chalky limestone, pale-yellowish-gray to light-olive-gray weathering pale grayish orange with lichen coating; this and similar units below relatively hard, cliff forming, porous; vertical calcite-filled rodlike burrow structures common near top; horizontal and irregular chalk-filled burrow structures common in lower half of unit; fragmentary Inoceramus shells common; FOSSILS - Inoceramus deformis, Ostrea congesta . . . . 2.6 43. Bentonite, olive-gray, speckled with biotite?, selenitic. . . . . . . . 0.03 42. Chalk, yellowish-gray to pale-yellowish-gray, intensively burrowed. . . 1.0 41. Shaly chalk, light-olive-gray to olive-gray, many irregular-shaped chalk-filled burrow structures; FOSSILS - Inoceramus sp. (fragments). . 0.5 40. Bentonite, light-olive-gray, stained grayish orange by limonite . . . 0.07 39. Chalky limestone, light-gray to light-olive-gray, weathering nearly white to pale grayish orange, lichen-covered where measured, shaly chalk zone near middle is riddled with threadlike and larger chalk- filled burrow structures; unit intensively burrowed throughout; FOSSILS - Ostrea congesta, Inoceramus (fragments) . . . . . . . . 4.3 38. Bentonite?, light-olive-gray, speckled with biotite, shaly, streaked with chalk . . . . . . . . . . . . . . . . . . . . . . . . . . 0.05 37. Chalky limestone, weathered yellowish gray to nearly white or pale grayish orange, lichen-covered where measured, many small, vertical, calcite- filled, rodlike burrow structures near middle, larger burrow casts common; FOSSILS - Inoceramus deformis (fragments), Ostrea congesta. . . . . 4.8 65