The obliquity of K-feldspar from schists, gneisses, and granites in the north-eastern part of the Hida metamorphic belt, central Japan
- 1 March 1984
- journal article
- Published by Mineralogical Society in Mineralogical Magazine
- Vol. 48 (346) , 53-63
- https://doi.org/10.1180/minmag.1984.048.346.08
Abstract
Most of 325 K-feldspars from the Hida metamorphic belt are characterized by diffuse 131 and 11 reflections. These K-feldspars are classified into eight obliquity types on the basis of the width of the 131 peak or the ratio of mean height of two outer peaks (131 and 11) to that of the middle composite peak. From the distribution of obliquity types and the microscopic characteristics of K-feldspars, this area is divisible into six zones.The feature of each zone is shown by the frequency distribution of eight obliquity types in each zone, which reflects the strength of later retrogressive effects. The frequency distribution of Δ values in each of the types IV-VIII provides further information on later events.The result of the K-feldspar study possibly indicates that the inversion of monoclinic to triclinic K-feldspar, characterized by the development of perthitic texture or crosshatched twinning, is sensitive to the degree of later retrogressive events. Some data on 2θ values of 04, 060 and 01 reflections in each types are presented.Keywords
This publication has 10 references indexed in Scilit:
- The obliquity of K-feldspar from schists, gneisses and granites in the upper Katakai-gawa area, central JapanThe Journal of the Geological Society of Japan, 1978
- The obliquity of K-feldspar from schists, gneisses and granites in the Donachui River area of the Santa Marta Mountains, northern Colombia.The Journal of the Japanese Association of Mineralogists, Petrologists and Economic Geologists, 1977
- Geological study of the Hida metamorphic belt in the eastern part of Toyama Prefecture, Central Japan (Part 1):On the tectonic division, the characteristics of the Funatsu stage plutonism, and the lithostratigraphic division of the metamorphic rocksThe Journal of the Geological Society of Japan, 1973
- On the occurrence of the characteristic minerals from the pelitic gneisses in the Tateyama-gawa (upper Hayatsuki-gawa) area, central JapanThe Journal of the Geological Society of Japan, 1973
- Alkali feldspars from part of the Galway granite, IrelandMineralogical Magazine, 1972
- The X-ray obliquity of potassic feldspar in the granites of Jämtland, Northern central SwedenGeologiska Föreningen i Stockholm Förhandlingar, 1972
- Alkali Feldspars from Gneisses and Granites of the Västervik Area, SE. SwedenGeologiska Föreningen i Stockholm Förhandlingar, 1968
- Feldspar structure and the equilibrium between plagioclase and epidoteAmerican Journal of Science, 1962
- Phase Relations of Potash Feldspar in MetamorphismThe Journal of Geology, 1957
- The microcline-sanidine stability relationsGeochimica et Cosmochimica Acta, 1954