Research dedicated to determining the best parameters in distinguishing fossil from the rock in which it is encased, while producing the best quality scan.
3. Studying Fossils
• Limit to studying
external
morphology (past)
• Destructive
methods to study
internal
morphology (past)
By Didier Descouens - Own work, CC BY-SA 3.0,
https://commons.wikimedia.org/w/index.php?curid=1
1113996
6. Past Paleontological CT-Scanning Applications
https://www.di
scovermagazin
e.com/planet-
earth/doctor-
to-the-
dinosaurs
Conroy and Vannier, 1984 Carlson et al., 2003
7. Purpose of this Study
• Determine if Xradia could distinguish a Palaeolagus fossil from the
rock composition in which it is encased
• Optimize parameters (Voltage, Projections, and Binning)
• Determine parameter combinations that gives the best quality scan
(time and cost efficient)
15. Segmentation Process
• Images inverted
• Histogram separated
• Otsu method
• Splitting ROIs
• Calculate signal to noise ratio
• Calculate the coefficient of
variation
https://www.prnewswire.com/news-releases/dragonfly-4-0-is-here-
the-engine-of-scientific-imaging-300836382.html
25. Examination of Signal to Noise Ratio and
Coefficient of Variation
• High signal to noise ratio = densities easier to distinguish
• High coefficient of variation= broadest histogram, easier to separate
32. Limitations and Future Work
• Filtering
• Excessive geometric magnification = fuzziness in image
• More specimens to scan!
• Puercan fossils in phosphatic concretions from Denver Basin
• Use ethafoam jackets for specimen prep
33. Acknowledgments
• My research at CU-Boulder is supported by a graduate assistantship
(GA) from the University of Colorado Museum of Natural History, and
a research assistantship (RA) from a David B. Jones Foundation grant
awarded to J. Eberle.
34. References Cited
• Babcock, L. E. 2014. Permineralization. AccessScience.
• Brochu, C. 2003. Osteology of Tyrannosaurus Rex: Insights from a nearly complete Skeleton and High-Resolution Computed Tomographic
Analysis of the Skull. Journal Of Vertebrate Paleontology 22:1—138.
• Carlson, W., T. Rowe, R. Ketcham, and M. Colbert. 2003. Applications of high-resolution X-ray computed tomography in petrology, meteoritics
and palaeontology. Geological Society, London, Special Publications 215:7—22.
• Conroy, G. C., and M. W. Vannier. 1984. Noninvasive Three-Dimensional Computer Imaging of Matrix-Filled Fossil Skulls by High-Resolution
Computed Tomography. Science 226:456—458.
• Evanoff, E., D. Prothero, and R. Lander. 1992. Eocene—Oligocene climatic change in North America: The White River Formation near Douglas,
east-central Wyoming. Eocene—Oligocene Climatic And Biotic Evolution 116—130.
• Gould, S. 1990. Wonderful Life. Norton.
• Otsu, N. 1979. A Threshold Selection Method from Gray-Level Histograms. IEEE Transactions on Systems, Man, and Cybernetics, 9(1), pp.62—
66.
• Ritman, E. L. 2004. Micro-Computed Tomography—Current Status and Developments. Annual Review of Biomedical Engineering 6:185—208.
• Sollas, W. J. 1903. A Method for the Investigation of Fossils by Serial Sections. Philosophical Transactions of the Royal Society B: Biological
Sciences 196:259—265.
•
Sutton, M. D. 2008. Tomographic techniques for the study of exceptionally preserved fossils. Proceedings of the Royal Society B: Biological
Sciences 275:1587—1593.
Revolutionized paleontology, been applied for 35 years
XRM further magnifies objects after electromagnetic radiation geometric magnification, and applies both geometric and optical magnification.
The skull of UCM 17758 that was evaluated is embedded in a rock matrix composed of an ash-rich mudstone from the White River Formation (Eocene – Oligocene)
3 parameters optimized, 7 combinations of parameters total
Sagittal region of the skull at different voltage levels
