STORIES FROM STONE: PETROGRAPHIC INVESTIGATION OF TYRANNOSAURUS REX AND TRICERATOPS HORRIDUS FROM THE HELL CREEK FORMATION, MONTANA.

The Hell Creek Formation is well known, globally, for its well-preserved variety of dinosaur fossils. However, what is not as well understood is the connection between microstructures preserved in bony materials and paleoenvironmental stressors that may have existed and impacted species during such times. In this study we analyzed dinosaur bone samples, specifically, Tyrannosaurus Rex and Triceratops Horridus that were collected at a field camp near Baker, Montana. The samples were first processed for photogrammetry via 3D modeling software to preserve these fossils in a virtual sense, for perpetuity and free 24/7/365 online access. Over 100 photographs were taken of each bone sample and then rendered through the 'Agisoft Metashape-TM' software and the end products uploaded on the industry-standard 'Sketchfab-TM' viewing platform. Thereafter, a total of ten, 30-micron thick, thin sections were created, and 125 microphotographs were analyzed for a variety of microstructures including osteocytes, secondary lamellar structures, and haversian canals. Results show that patterns of abundance of osteocytes and bone growth were impacted by stressors including access to a healthy food supply.