Neutronographic Texture Investigation of Metamorphic Rocks

摘要

The neutron time-of-flight (TOF) diffraction is well suited for preferred orientation studies in low symmetric materials, for example, in quartzitic rocks, because of the simultaneous recording of the whole Bragg pattern. The unnormalized pole figure values are determined as integrated intensities of the corresponding diffraction peaks by a computer fit of the TOF spectrum. Unfortunately, many of natural rocks consist of more than one mineral. Therefore, the TOF diffraction pattern is a uperposition of spectra from all components, i.e. there is a lot of overlappings of different reflections. In this case the question arises about the reliability of the experimental pole figures. On the basis of complete experimental pole figures methods and criteria are discussed to check and to imrove their internal and external compatibility. These procedures may have importance in the study of other low symmetry of multiphased systems also. The efficiency of the presented methods is demonstrated for selected experimental results. 9 refs.; 4 figs.; 1 tab. (Atomindex citation 19:104472)