华南型块状硫化物矿床中的胶黄铁矿及其退火作用

Melnikovite in the South China Type Massive Sulfide Deposits and Its Annealing

华南型块状硫化物矿床中胶黄铁矿的退火过程从早到晚可分成三个阶段:原始晶化变胶体阶段、不等粒变晶生长阶段和颗粒界面调整阶段。不同阶段的矿石各具特征性的结构,反映了燕山期侵入活动对于先存胶黄铁矿的不同程度热效应。

Melnikovite, one of the most important ore minerals in the South China type massive sulfide deposits, was originally a sedimentary product of submarine volcanic hydrothermal fluids and has been annealed remarkably in the subsequent geological history. Based upon microscopic studies on ore textures, the annealing process of melnikovite in these deposits might be divided into three stages: primary crystallization, seriateblastic growth and adjustment of grain boundaries. Ores of these three stages usually occupy positions progressively closer to the Yanshanian intrusives in the above sequence, indicating the predominant role played by the thermal effect of these intrusives on the annealing of melnikovite. Accompanying the recrystallization of sulfides, the annealing process has also resulted in a redistribution of minor elements between melnikovite and pyrite.