Paleontology and paleoecology of the Nada member of the Borden Formation (lower Mississippian) in eastern Kentucky

Nada Member of the Borden Formation (Mississippian) in northeastern Kentucky was the delta platform deposit of the Borden Delta. It consists of mainly mudstones with carbonates and siltstone intercalations. Biostratigraphic study bears out that the Nada Member has a middle Osagean age, and once again confirms the westward progradation of the Borden Delta.; Two sedimentary facies were recognized in the Nada. The interdistributary mudstone facies is predominantly greenish, gray mudstones, shales, with some minor siltstones. This facies represents a quiet, muddy, soft substratum. The carbonate tempestite facies was represented mostly by carbonate lenses and stringers. Under thin-section study, these carbonates contain various mounts of terrestrial ingredients. Based on field observation and microscopic study, this facies was interpreted as storm deposits below the fair weather wave base.; Community paleoecological study was carried out with the application of the concepts of community component, tiering, and guilds. Biotic interactions were represented in the Nada fauna by the platyceratids-crinoids, the platyceratids-tabulate corals, and the tabulate coral-crinoid relations. The Nada community was compared with the Edwardsville community of the southern Indiana because they existed in the same environment (mudstone facies of the Borden delta platform) but lived at different times. The Edwardsville community has more diverse taxa and more guilds than the Nada community. The increase of the diversity is a result of the increase in the number of guilds, indicating that no guild packing occurred. The community development patterns displayed by the two communities are against coordinated stasis, but for coincident relative stability.; Crinoids are the predominant group of fossils in the Nada Member. One new genus and four new species have been established. The dominant crinoid group in the Nada is monobathrid crinoids, followed by cladids, and disparids. The fact that monobathrid camerates dominated the Nada fauna in the mudstone facies is against the belief that crinoid faunas dominated by monobathrid camerates were largely found in carbonate facies.