A Study of the Composition, Distribution, and Genesis of Pyrrhotite In the Copper Cliff Offset, Sudbury, Ontario, Canada
A Study of the Composition, Distribution, and Genesis of Pyrrhotite In the Copper Cliff Offset, Sudbury, Ontario, Canada
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加拿大安大略省萨德伯里铜崖偏移中磁黄铁矿的成分、分布和成因研究
DOI：
10.3749/canmin.1400040
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发表时间：
2015
影响因子：
0.9
通讯作者：
A. McDonald
中科院分区：
文献类型：
--
作者：
S. Gordon;A. McDonald
利用粉末x射线衍射数据、Rietveld分析、SEM-EDS、磁性胶体、光学岩石学技术和激光烧蚀- icp - ms等技术，对加拿大安大略省Sudbury铜崖偏移岩脉（CCOD）中5个矿体（830、865、880、890和100 OB）中的磁黄铁矿（Po）进行了研究，目的是：(1)定量确定NC（非磁性，对称性高于单斜）和4C（磁性，对称性高于单斜）Po的分布；(2)表征两种多晶态的主要、次要和微量元素化学特征；(3)确定提高NC - Po稳定性的因素。结果证实NC和4cpo都存在，比值在0到0.97之间变化。一般来说，在取样的OB中，4cpo是主要的多晶型，除了100 OB，它主要是NC Po。
Pyrrhotite (Po) from five orebodies (830, 865, 880, 890, and 100 OB) in the Copper Cliff Offset Dike (CCOD) at Sudbury, Ontario was studied using powder X-ray diffraction data and Rietveld analysis, SEM-EDS, magnetic colloid, optical petrographic techniques, and Laser Ablation-ICP-MS in order to: (1) quantify the distribution of NC (non-magnetic, symmetry higher than monoclinic) and 4C (magnetic, monoclinic in symmetry) Po; (2) characterize the major, minor, and trace-element chemistries of both polymorphs; and (3) determine the factors enhancing the stability of NC Po. Results confirm that both NC and 4C Po are present, with ratios varying between 0 to 0.97. In general, 4C Po is the dominant polymorph within the sampled OB, with the exception of the 100 OB, which is dominated by NC Po.
Mineral chemistry indicates that there is an almost complete compositional overlap between the major, minor, and trace-element compositions of NC and 4C Po from the CCOD. The data also show that both polymorphs are slightly metal-deficient relative to the ideal chemistry of 4C Po, Fe7S8. There were no significant differences found in the Ni contents of either polymorph. Data revealed that the main mineralogical difference between the five OB was the presence of ilmenite in the 830, 865, 880, and 890 OB, whereas magnetite dominates in the 100 OB.
Mineralization occurs along the eastern margin of the 830–890 OB, in contrast to the 100 OB, where mineralization occurs in the center of the dike. The increased abundance of NC Po in the 100 OB may be explained by this difference in the style of mineralization, specifically, the proximity of ore to the surrounding country rock. Therefore, f O2 may have directly influenced the distribution and stabilization of NC Po, which would then impact the observed NC:4C Po ratios in the selected OB.
影响因子：
3.8
作者：
Jochum, Klaus Peter;Wilson, Steven A.;Woodhead, Jon D.
通讯作者：
Woodhead, Jon D.