Summary of the paleontology of the Santa Fe Group (Mio-Pliocene), north-central New Mexico
— Barry S. Kues and Spencer G. Lucas

The Santa Fe Group, as restricted by Galusha and Blick (1971) to rocks of the type and contiguous areas, crops out extensively in and around the Rio Grande valley from Santa Fe northward past Espanola to beyond Abiquiu and Ojo Caliente (fig. 1). Strata lithologically and temporally equivalent to those present in the type area also are exposed south of Santa Fe (Kelley, 1977; Kelley and Northrop, 1975), but will not be considered in this report. Deposition of the Santa Fe Group extended from late Hemingfordian (medial Miocene) to Hemphillian (early Pliocene) time (Galusha and Blick, 1971; Mac Fadden, 1977), a period of about 12 million years. Characteristic Santa Fe exposures are buff, brown, red, gray or green colored shales, sandstones and conglomerates that contain numerous white ash layers and erode into highly dissected expanses of badlands. From these beds has come one of the most abundant, diverse and continuously sampled vertebrate faunas in the world; the Santa Fe Group is arguably the most thoroughly and carefully collected stratigraphic unit in New Mexico. The purposes of this paper are to summarize briefly the paleontology of the Santa Fe, to describe the nature of fossil collections and work in progress, and to suggest areas of profitable future research.