An analytical and experimental study of zoning in plagioclase |
| |
| Authors: | Robert K Smith Gary E Lofgren |
| |
| Institution: | 1. Robert K. Smith, Department of Geosciences, University of Southern Colorado, Pueblo, Colorado 81001, USA;2. Gary E. Lofgren, Geology Branch, SN6, NASA Johnson Space Center, Houston, Texas 77058, USA |
| |
| Abstract: | A detailed electron microprobe study has been conducted on natural and experimentally grown zoned plagioclase feldspars. Discontinuous, sector, and oscillatory chemical zoning are observed superimposed on continuous normal or reverse zoning trends. The relative accuracy of 3 element (Na, Ca, K) microprobe traverses was found statistically to be 2 mole percent. Comparison of microprobe data on natural zoned plagioclase with zoned plagioclase grown in controlled experiments has shown that it may be possible to distinguish zonal development resulting from physio-chemical changes to the bulk magma from zoning related to local kinetic control on the growth of individual crystals. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
