Development of micro-tomography imaging system for rock and mineral samples

Micro tomography imaging system for rocks and mineral samples was developed at the SPring-8. The experiments were performed on "in-vacuum type" undulator beam line and bending magnet beam line. Transmission images were measured with an image detector that consists of a fluorescent screen, relay lens, and cooled CCD camera. convolution back projection method was used to reconstruct tomographic images. As the results of performance test, spatial resolution was about 17 mu m, and the contrast resolution was about 10% in the X-ray linear attenuation coefficient. Three-dimensional structures and textures of some rocks and materials were obtained with the tomography system. Especially the three-dimensional tomographic images of chondrules from Allende meteorie, including barred olivine chondrule were successfully obtained.