Guide to the late Pennsylvanian paleontology of the Upper Madera Formation, Jemez Springs area, north-central New Mexico
— Barry S. Kues

Late Pennsylvanian (Missourian to middle Virgilian) strata of the upper part of the Madera Formation north of Jemez Springs town are approximately 250 ft thick, and contain diverse faunas from varied marine facies. Although a well known collecting area for decades, relatively little has been published on these fossils. Here, more than 90 taxa from this sequence are briefly described and illustrated, and their stratigraphic ranges indicated mainly by noting their distribution in two reference sections, one near the Jemez Ranger Station and the other opposite Hummingbird Camp, about 4 mi to the north. Most of these taxa are brachiopods (33 species), gastropods (26 species) and bivalves (26 species), but information on fusulinids, corals, bryozoans, cephalopods, scaphopods, rostroconchs, trilobites, echinoids, crinoids and vertebrates is also included. Total diversity is even greater than is indicated here, because some poorly preserved rare species are not included, and the taxonomic composition of some groups, such as bryozoans and corals, remain to be studied. The majority of the species observed in the Jemez Springs Late Pennsylvanian sequence are also present in strata of equivalent age in the Midcontinent region and/or Texas, but some are apparently endemic to the Rocky Mountain area or to New Mexico, and a few are new species. Several distinctive faunal assemblages occur in these strata, characterizing different depositional environments.