36. Shaly chalk, weathered light olive gray to pale yellowish brown or grayish orange, with very thin bentonite seam nearly at base and with rare small limonite nodules, many irregular-shaped chalk-filled burrow structures. 0.45 35. Chalky limestone weathered pale yellowish gray to pale yellowish orange, lichen-covered where measured, 0.1-foot-wide limonite nodule near base, irregular-shaped chalk-filled burrow structures common in lower half; vertical calcite- and limonite-filled rodlike burrow structures abundant in middle part of unit; FOSSILS - Inoceramus deformis (whole and fragmentary), Ostrea congesta . . . . . . . . . . . . . . . . . . . . . . . . . . 2.95 34. Bentonitic shale, light-olive-gray, slightly biotitic . . . . . . . . . 0.13 33. Chalky limestone, weathered pale yellowish gray to pale grayish orange, lichen-covered where measured, sparse vertical calcite- and limonite- filled burrow structures; shaly chalk forms re-entrant 0.3 foot above base; FOSSILS - Inoceramus sp. (fragments). . . . . . . . . . . . . . 1.5 32. Shaly chalk, light-olive-gray, argillaceous, with nearly white lenses of chalk, and with burrow structures near top. . . . . . . . . . . . . . . . 0.08 31. Chalky limestone, like 33, with numerous vertical calcite-filled and many irregular-shaped chalk-filled burrow structures; FOSSILS - Inoceramus fragments (probably Inoceramus deformis). . . . . . . . . . . . . . . . . . 1.0 30. Shaly chalk, light-olive-gray, argillaceous, intensively burrowed horizon- tally . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 29. Chalky limestone, like 33, only mottled with light gray; scattered blebs of pyrite, some oxidized to limonite; many vertical calcite-filled rodlike burrow structures; many irregular-shaped chalk-filled burrow structures 2.4 28. Shaly chalk and chalk, light-olive-gray weathering yellowish or pale yellowish gray, upper shaly part argillaceous, all with irregular-shaped chalk-filled burrow structures, chalk bed in middle with vertical calcite- or limonite-filled rodlike burrow structures; FOSSILS - Inoceramus deformis (mostly fragmentary), Ostrea congesta . . . . . . . . . . . . . . . 1.15 27. Bentonite, light-olive-gray, biotitic . . . . . . . . . . . . . . . . . . 0.05 26. Chalky limestone, weathered pale yellowish gray to nearly white, lichen- covered where measured, shaly at base and in zone 1.4 feet below top, limonite nodule 0.8 foot above base, many irregular-shaped chalk-filled burrow structures above upper shaly zone, vertical calcite-filled rod- like burrow structures, sparse fragments of Inoceramus; FOSSILS - Inoceramus deformis (whole and fragmentary), Ostrea congesta . . . . . . . . . . 3.8 25. Bentonite, light-olive-gray . . . . . . . . . . . . . . . . . . . . . . 0.05 24. Chalky limestone, like 26, with some irregular-shaped chalk-filled bur- row structures and pyrite- and calcite-filled rodlike burrow structures; FOSSILS - Inoceramus sp. (fragments). . . . . . . . . . . . . . . . . . 2.0 23. Shaly chalk, weathered light olive gray, stained dark yellowish orange by limonite, many irregular-shaped chalk-filled burrow structures; FOSSILS - Inoceramus deformis (whole), Ostrea congesta. . . . . . . . . 0.1 22. Chalky limestone, like 26, with sparse irregular-shaped chalk-filled burrow structures; FOSSILS - Inoceramus deformis (whole and fragmentary), Ostrea congesta . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.7 21. Bentonite, light-olive-gray, weathering dark yellowish orange, biotitic 0.1 20. Chalky limestone, like 26, with sparse irregular-shaped chalk-filled burrow structures; FOSSILS - Inoceramus sp. (fragments), Ostrea congesta 2.2 19. Bentonite, light-olive-gray, stained dark yellowish orange by limonite, biotitic, with sparse selenite crystals . . . . . . . . . . . . . . . . . 0.05 18. Shaly chalk, weathered light olive gray to yellowish gray, 0.1-foot-thick selenite seam 0.75 foot below top, sparse limonite nodules, upper part has irregular-shaped chalk-filled burrow structures; FOSSILS - Inoceramus deformis (whole and fragmentary), Ostrea congesta . . . . . . . . . . 1.55 66