[AndrewC]

But crocodiles and turtles had already evolved at the time of the great extinction 65 million years ago. How did they survive?

"These animals live at the intersection of aquatic and terrestrial environments, in estuarine waters and river beds, which might have afforded some protection against the more extreme effects of environmental change, hence giving them more time to adapt," the researchers wrote.

Paleocene hadrosaurs?

Fassett, J, R.A. Zielinski, & J.R. Budahn, 2002. Dinosaurs that did not die; evidence for Paleocene dinosaurs in the Ojo Alamo Sandstone, San Juan Basin, New Mexico. In: Catastrophic events and mass extinctions; impacts and beyond. (Eds. Koeberl, C. & K. MacLeod): Special Paper - Geological Society of America 356: 307-336. (2002).

AB: Palynologic and paleomagnetic data confirm a Paleocene age for the Ojo Alamo Sandstone (and its contained dinosaurs) throughout the San Juan Basin of New Mexico. The recently reported discovery of 34 skeletal elements from a single hadrosaur in the Ojo Alamo provides unequivocal evidence that these bones were not reworked from underlying Cretaceous strata. Geochemical studies of samples from several single-dinosaur-bone specimens from the Paleocene Ojo Alamo Sandstone and the underlying Late Cretaceous (Campanian) Kirtland Formation show that mineralized bones from these two rock units contain distinctly different abundances of uranium and rare-earth elements and demonstrate that Cretaceous and Paleocene bones were mineralized at different times when mineralizing fluids had distinctly different chemical compositions. These findings indicate that the dinosaur bone from the Paleocene Ojo Alamo is indigenous and not reworked. These data show that a relatively diverse assemblage of dinosaurs survived the end-Cretaceous asteroid-impact extinction event of 65.5 Ma. The San Juan Basin's Paleocene dinosaur fauna is herein named the Alamoan fauna. Magnetic-polarity chronology shows that these survivors lived for about one million years into the Paleocene and then became extinct around 64.5 Ma. We suggest that a plausible survival mechanism for this Lazarus fauna may have been the large numbers of buried dinosaur eggs, laid just before the asteroid impact occurred. These buried eggs would have provided a safe haven for developing dinosaur embryos for the first one to two years after the impact, thereby making it possible for them to survive the worst of the impact's early devastation.

COMPELLING NEW EVIDENCE FOR PALEOCENE DINOSAURS IN THE OJO ALAMO SANDSTONE, SAN JUAN BASIN, NEW MEXICO AND COLORADO, USA.

The fully documented Paleocene dinosaur bone from the Ojo Alamo Sandstone at the San Juan River site, bolsters conclusions [5, 1] that the dinosaur-bone assemblage from the Ojo Alamo Sandstone in the vicinity of Alamo Wash is also of Paleocene age, even though vertebrate paleontologists have assigned a Lancian age to that assemblage.

[Junior]

Cool. Thinks for the link. I know they're sure the bone has not been worked up from pre-K-T strata. However, I wonder if they've allowed for a bones that might have weathered out of pre-K-T strata (much like we find happening nowadays in places like Mongolia) and then being re-interred, as it were, in later strata. I wonder how one would check for that.