At that time, much of the region was part of river-plains similar to the present southeastern United States with sub-tropical climate and vegetation of the Cretaceous period or the Age of Reptiles.Rivers draining the Western Mountains deposited layer upon layer of sediments which over alleged millions of years compacted to form the sandstones, mudstones, clays, and shales that form the Montana Badlands landscape according to the Makoshika State Park web site. It usually refers to any clay that swells and shrinks.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).It's important to note that the authors concluded: "There was no statistical RC difference between the bones and that of the organic material and dating of mammoth bones is [thus] reliable." S. Examples of other magafauna RC dates include 50 mammoths buried together near Hot Springs, South Dakota, USA. All contain some corrected percent of modern C-14 (PMC'S). C-14 dates for carbon-containing material from the Chesapeake Bay or Chicxalub core samples would be useful for comparison.A date of ~26,000 years BP was obtained for bones that were devoid of collagen. Some examples from many references include: marble, 0.060-0.932 PMC, A. Controversial radiometric dates have been recorded for material from Hawaiian volcanic eruptions in 1800-1801 and the Hawaiian magma there gave dates of 1.41 and 1.60 million years BP according to G. Moreover, natural diamonds thought to be "greatly in excess of 100 million years" gave apparent variable RC dates of "64.9 ± 0.4 ka BP to 80.0 ± 1.1 ka BP.Nonetheless, dinosaur bone apatite had been successfully RC dated in the late 1980's/early 1990's and significant amounts of C-14 were detected and reported.
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.
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.
It is very slippery in wet, and crunchy in dry condition, according to paleontologist Otis Kline.
Triceratops and Hadrosaur locations: The exact location for the Triceratops femur is 47 degrees 6 minutes & 18 seconds North by 104 degrees, 39 minutes & 22 seconds West. The highest nearby point is approximately 201 m southwest of the find and is 669 m above sea level.