John has brought this rather entertainingly-titled abstract to my attention:

Fassett, J.E. 2007. The documentation of in-place dinosaur fossils in the Paleocene Ojo Alamo Sandstone and Animas Formation in the San Juan Basin of New Mexico and Colorado mandates a paradigm shift: dinosaurs can no longer be thought of as absolute index fossils for end-Cretaceous strata in the Western Interior of North America. New Mexico Geology 29(2):56.

If you follow the link, this is actually found under the abstracts for the New Mexico Geological Society Spring Meeting (pdf), and the first paragraph reads thus:

Extensive geochronologic studies of the rocks adjacent to the Cretaceous-Tertiary (K-T) interface in the San Juan Basin have now provided compelling data attesting to the Paleocene age of the dinosaur-bearing Ojo Alamo Sandstone in New Mexico and the Animas Formation in Colorado. These data consist of radiometric age determinations for Cretaceous strata underlying the K-T interface and palynologic, paleomagnetic, and geochemical evidence attesting to the Paleocene age of the strata above the K-T interface. The identification of the paleomagnetic normal interval – C29n – in the dinosaur-bearing lower part of the Ojo Alamo Sandstone in the southern San Juan Basin at multiple localities allows for the precise dating of the last occurrence of Paleocene dinosaurs at the top of chron C29n at 64.432 Ma.

Head over to Evolving Thoughts for a discussion of the second paragraph, which fulfils the promise of the title with liberal use of the terms “conventional wisdom”, “entrenched dogma”, and “paradigm”. The tone is interesting given that, assuming the data are good, the interpretation is straightforward. Here’s the sequence of magnetic reversals over the KT boundary (black is normal polarity, white is reversed – a link for the confused):

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