Mid-Cretaceous molluscan record from west-central New Mexico
— William A. Cobban and Stephen C. Hook


Molluscan fossils are fairly abundant in most of the mid-Cretaceous rocks of west-central New Mexico The important guide fossils are reviewed and illustrated. The fossils are from the following rocks. from oldest to youngest: middle Cenomanian into lower part of upper Cenomanian, intenongued Dakota Sandstone and Mamas Shale: upper Cenomanian into lower or middle Turonian, Rio Salado Tongue of Mancos Shale; upper Cenomanian into upper Turanian or lower Coniacian, main body of Manors Shale; upper part of lower Turonian into lower part of middle Turonian. Atarque Sandstone; middle Turanian. Semilla Sandstone Member of Mancos Shale; middle Turonian into lower part of upper Turanian. Tres Hermanos Formation; upper Turonian. Juana Lopez Member of Mancos Shale, Pescado Tongue of Mancos Shale, D-Cross Tongue of Mancos  Shale, upper pan of Tres Hermanos Formation and locally part or all of Gallup Sandstone: lower Coniacian, upper part or locally all of Gallup Sandstone. Younger rocks of later Coniacian age. such as the Mulatto Tongue of the Mancos Shale. arc not treated.

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Recommended Citation:

  1. Cobban, William A.; Hook, Stephen C., 1989, Mid-Cretaceous molluscan record from west-central New Mexico, in: Southeastern Colorado Plateau, Anderson, Orin J.; Lucas, Spencer G.; Love, David W.; Cather, Steven M., New Mexico Geological Society, Guidebook, 40th Field Conference, pp. 247-264. https://doi.org/10.56577/FFC-40.247

[see guidebook]