摘要
本文对我国一些典型的矽卡岩型矿床中的石榴石进行了电子探针、X-射线粉晶衍射、红外光谱、吸收光谱和穆斯堡尔谱研究。这些石榴石均属于钙榴石系列。石榴石晶格的畸变立方体位置中发生的Fe<sup>2+</sup>、Mg<sup>2+</sup>、Mn<sup>2+</sup>置换Ca<sup>2+</sup>及八面体位置中Al<sup>3+</sup>、Fe<sup>3+</sup>、或Cr<sup>3+</sup>之间的置换是控制其晶胞参数a。、红外光谱及吸收光谱特征带位移的主要晶体化学因素;穆斯堡尔谱参数有效地限定了石榴石中铁的价态和占位特征,反映了其形成时的氧化还原条件。依据石榴石的波谱学资料不仅可以判断其所属系列和确定其端元组分,而且能辅助矽卡岩的分带和判定石榴石形成的物理化学条件。
Garnets from some typical skarn ore deposits in China are analyzed by electron micro- probe, X-ray powder diffraction, infrared spectra, absorption spectra and Mossbauer spectra, etc. The garnets belong to ugrandite defined by A. N. Winchell (1951). That Ca^(2+) is substituted by Fe^(3+), Mg^(2+) and Mn^(2+) in distorted cubic sites and Al^(3+) by Fe^(3+) or Cr^(3+) in octohedral sites of the garnets is the main crystal chemical factor which controls cell parameter ae and displacements of typical infrared spectra and absorption spectra of the garnets. Mossbauer spectrum parameter effectively confines the valence of iron ion and its specific orientation, which could reflect the oxidation-reduction condition when the gar- nets were produced. Spectroscopic data could not only be used to identify the solid series and end compo- nents of garnets, but also be helpful to skarn zoning and recognition of physical-chemical condition of their formation.
出处
《安徽地质》
1992年第4期1-12,共12页
Geology of Anhui
