Semilla Sandstone, a New Member of the Mancos Shale in the Southeastern Part of the San Juan Basin, New Mexico: Definition, Description, and Paleontology of a New Stratigraphic Unit

Stratigraphy and Regional Relationships of a Reference Section for the Juana Lopez Member, Mancos Shale, in the San Juan Basin, New Mexico: The Lithology and Faunal Zonation of a Well-exposed Surface Section are Described, and the Section is Compared with the Abnormally Thin Section at the Type Locality