X-ray Diffraction Computed Tomography of a Fossil Bone Sample

A fossil bone sample, a humerus (”upper arm”) of a prehistoric fish, Eusthenopteron Foordi, has been studied using a combination of X-ray diffraction, computed tomography and synchrotron radiation. The technique has in this thesis been called X-ray diffraction computed tomography. It has been attempted to obtain three-dimensional tomographic images of sample regions containing different minerals, as well as to determine crystallite orientation properties of the different minerals.The sample has been found to consist of hydroxylapatite, barite, calcite, quartz and pyrite. Three-dimensional tomographic images of the four first minerals have been made using the filtered backprojection algorithm. Image artifacts were reduced by combining recorded intensity from several Bragg peaks and by combining data from two separate tomographic measurements of the sample.A fraction of the hydroxylapatite crystallites appear to have a preferredorientation. The direction of this preferred orientation has been deter-mined for some regions close to the sample edge.

Internal structure of shales by coherent X-ray diffraction imaging

info:eu-repo/semantics/nonPublishe