APPENDIX Measured Sections for Field Trip Stops Descriptions of sections at the various stops mostly have not been published hitherto and are included here to benefit field trip participants as well as future visitors to this area. Description of Section Measured at STOP 1 GREENHORN LIMESTONE Lincoln Limestone Member Feet 33. Shaly chalk, similar to 31; bentonite is 0.2 foot thick, nearly white, weathers dark yellowish orange; FOSSILS - Inoceramus sp., fish remains 2.8 32. Chalk, weathered yellowish gray to dark yellowish orange, soft, lami- nated, speckled; FOSSILS - Inoceramus pictus, fish remains. . . . . . 0.2 31. Shaly chalk, weathered yellowish gray to dark yellowish orange, soft, laminated, speckled, with numerous very thin lenses of skeletal lime- stone; bentonite is 0.13 foot thick, very light gray, slightly silty; FOSSILS - Inoceramus sp., fish remains. . . . . . . . . . . . . 1.5 30. Chalky limestone, weathered grayish orange to dark yellowish orange, soft to medium-hard, speckled, uneven thickness; FOSSILS - Inoceramus pictus, fish remains. . . . . . . . . . . . . . . . . . . . . . . . 0.2 29. Shaly chalk, similar to 31; FOSSILS - Inoceramus pictus, fish remains . 1.9 28. Skeletal limestone and shaly chalk, weathered dark yellowish orange; limestone is very fine grained, hard, thinly laminated, in very thin lenses and lensing layers; chalk soft, laminated; FOSSILS - Inoceramus sp., fish remains . . . . . . . . . . . . . . . . . . . . . . . . 0.7 27. Skeletal limestone and bentonite; limestone is light olive gray, upper beds weathering pale yellowish brown to dark yellowish orange, hard, limonite-speckled, petroliferous odor, mostly Inoceramus shell fragments and prisms; one bed of softer chalky limestone in upper part of unit; bentonite is 0.3 foot thick, light gray to light olive gray; FOSSILS - Inoceramus pictus, Ostrea sp., fish remains . . . . . . . . . . . . 1.6 Thickness of exposed part of Lincoln Limestone Member 8.9 GRANEROS SHALE 26. Shale, similar to 24; FOSSILS - Inoceramus sp. (prisms), Hedbergella, fish remains. . . . . . . . . . . . . . . . . . . . . . . . 1.1 25. Skeletal limestone, light-olive-gray weathering dark yellowish orange, well-cemented, quartz sandy, thinly laminated to gently cross-laminated, petroliferous odor where fresh, composed largely of Inoceramus prisms; FOSSILS - Ostrea beloiti, Inoceramus rutherfordi, Plesiacanthoceras sp., fish remains. . . . . . . . . . . . . . . . . . . . . . . . 0.3 24. Shale, weathered light olive gray to dark yellowish orange, streaked with very fine grained quartz sand or silt, soft, with specks of car- bonaceous matter; FOSSILS - Inoceramus sp., Ostrea sp., Hedbergella, Heterohelix, fish remains . . . . . . . . . . . . . . . . . . 1.4 23. Bentonite and septarian concretions; bentonite 1.0 foot thick, very light gray weathering dark yellowish orange, slightly silty, speckled with biotite?; concretions dusky-yellow to nearly white, up to 4.0 feet across; FOSSILS - Ostrea beloiti, Inoceramus rutherfordi. . . . 1.4 48