Phase relations of pyrrhotite
Phase relations of pyrrhotite
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DOI：
10.2113/gsecongeo.60.7.1431
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发表时间：
1965-11
期刊：
影响因子：
5.8
通讯作者：
G. Desborough;R. H. Carpenter
中科院分区：
文献类型：
--
作者：
G. Desborough;R. H. Carpenter
FeS-FeS_2体系的暂定相图显示，黄铁矿-磁黄铁矿在315℃附近的近等温相界处向下终止，在这一相界之上，六方磁黄铁矿有一个超晶胞，其中a=2A，c=7C，这是以前没有发现的。在这一边界的正下方，六方磁黄铁矿(a=2A，c=5C的超晶胞)占据了46.6-50%Fe之间的大部分区域。在一侧为单斜磁黄铁矿(化学计量比)的窄双相场和一侧为硫铁矿的低温(<；140℃)双相场之间，该场向下减小。可能影响磁黄铁矿与黄铁矿组成的许多过程限制了磁黄铁矿地质温度计的可靠性。
A tentative phase diagram for the system FeS-FeS 2 shows the pyrite-pyrrhotite solvus termination downward at a nearly isothermal phase boundary near 315 degrees C. Above this boundary, hexagonal pyrrhotite has a supercell in which a=2A, c=7C, not previously recognized. Immediately below this boundary, hexagonal pyrrhotite (supercell with a=2A, c=5C) occupies most of the field between 46.6 and 50 percent Fe. This field decreases downward, between a narrow two-phase field with monoclinic pyrrhotite (stoichiometric Fe (sub ) S 8 ) on one side, and a low-temperature (<140 degrees C) two-phase field with troilite on the other. The numerous processes that may affect the composition of pyrrhotite with pyrite limit the reliability of the pyrrhotite geothermometer.