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Geology of the Triceratops and Hadrosaur excavation sites: The Triceratops and Hadrosaur femurs were found in popcorn clay. The color varies from grey to grey-green to green to tan; it is found in distinct thick strata.
It contains much volcanic material such as bentonite, or clays such as montmorillonite or vermiculite.
Abstract: The discovery of collagen in a Tyrannosaurus-rex dinosaur femur bone was recently reported in the journal Science.
well above the bone strata; this suggests that the RC date for the bones was reliable as clay acts as a barrier. Significant age discrepancies between C-14 and other radiometric techniques In spite of sometimes erratic C-14 dates, there are far more controversial dates when C-14 datable material or historical dates for magma flows are compared with potassium/argon dates. Lovering et al., the K/Ar dates for tektites ranged from 700,000 B. Fission-track dating ranged from 30,000 to 800,000 BP and was interpreted as consistent with K/Ar ages. Gill, had RC dated charcoal and calcareous nodules as they were found with "australites." Thus Lovering et al. Helens in the United States ranged from 350,000 to 2,700,000 years BP using K/Ar dating according to G. Had carbon-datable material been RC dated from the cores such as shells, carbonized wood, amber, charcoal and bones, would they have discovered a date much closer to the present as with the australites or as with the wood buried deep in the Prudhoe Bay permafrost?Fig.3a shows the Triceratops femur dissection using carefully cleaned saw with the bone supported by wood frame and plaster of Paris cast.Identification of the femur was made by comparing with photos and descriptions from a standard paleontology text-book and comparison with a young adult femur, 107 cm long.It can also be seen from Fig.1a that the femur was located very close to the surface.Because of its proximity to the surface, the paleontologists had to contend with some roots of living plant material before reaching the bone.Photos were unavailable for the Hadrosaur femur excavation. 1a -1d (right) shows the sequence of extracting the Triceratops femur.In Fig.1-d it rests on the pedestal of earth after excavation and before adding the protective coating. 1a to 1d as the Triceratops femur bone was being extracted from about 1 m in depth, which was about 20 m below the top of the Montana Badlands [60 m of strata designated Cretaceous].Perhaps the most informative documentation of Figs.1 and 2 is that they show the sequence of excavating a 122 cm long Triceratops femur from discovery, to pedestal, to plaster, to separation. Photos 3a-3c are of Triceratops femur bone during and after sawing; photo 3d is a portion of Glendive MT Dinosaur and Fossil Museum field research station; photomacrograph 3e is of material from bone interior containing bone collagen.When it was learned in 2005 that Triceratops and Hadrosaur femur bones in excellent condition were discovered by the Glendive (MT) Dinosaur & Fossil Museum, Hugh Miller asked and received permission to saw them in half and collect samples for C-14 testing of any bone collagen that might be extracted.Indeed both bones contained collagen and conventional dates of 30,890 ± 380 radiocarbon years (RC) for the Triceratops and 23,170 ±170 RC years for the Hadrosaur were obtained using the Accelerated Mass Spectrometer (AMS).