High resolution X-ray computed tomographic (CT) images of chondrites and a chondrule

In order to study internal textures of meteorites, images were obtained by X-ray computer tomography (CT). This combined high resolution X-ray radiography and computer tomography system belongs to the so-called third generation type with a micro-focus X-ray source and a linear CCD detector with 2048 elements. This allows a spacial resolution of a few μm in the images. Samples examined include the Moorabie meteorite (L3), Allende meteorite (CV3), and a chondrule removed from Allende meteorite. In images, Fe-Ni alloy, troilite, and silicates can be distinguished clearly, and chondrules can be resolved from their Fe-rich rims in Moorabie meteorite. In Allende Fe-Ni alloy, pentlandite, and silicates can be distinguished, and chondrules, CAI's, and matrix can be recognized. Many euhedral crystals, probably olivine and/or pyroxene, were identified in a chondrule, suggesting that the chondrule has a porphyritic texture. In addition to minerals or their assemblages, holes can be identified by the X-ray CT method and were found in chondrules in Allende.