The Tansill Formation is a geologic formation in southeastern New Mexico and west Texas, United States.DeFord et al. 1928 It preserves fossils dating back to the late Guadalupian Age of the Permian period.Tait et al. 1962
Description
The formation consists of limestone, siltstone, and anhydrite that is extensive in the subsurface in southeastern New Mexico and west Texas. The formation is mostly limestone in the south and west, around the rim of the Delaware Basin, and grades into anhydrite in the north and east. It forms the top of the Capitan reef but dips steeply into the subsurface.DeFord and Riggs 1941 It has a total thickness of .Newell et al. 1953 It overlies the Yates Formation.King 1948 The formation is part of the Artesia Group, which is interpreted as a shelf rock sequence.
History of investigation The formation was first named by DeFord et al. in 1938 and formally defined in 1941 and assigned to the (now abandoned) Whitehorse Group. Tait et al. assigned it to the newly defined Artesia Group in 1962.
See also
List of fossiliferous stratigraphic units in New Mexico Paleontology in New Mexico
Footnotes
References
Newell, N.D., Rigby, J.K., Fischer, A.G., Whiteman, A.J., HIckox, J.E., and Bradley, J.S., 1953, The Permian reef complex of the Guadalupe Mountains region, Texas and New Mexico; a study in paleoecology: San Francisco, W.H. Freeman and Company