关键词: 富乐铅锌矿, 黄铜矿, 锌砷黝铜矿, 黝铜矿, MVT型矿床

Abstract: The mineral assemblage in the MVT Pb-Zn deposits is generally simple because the copper minerals of this type of deposit
are very rare. As one of the largest MVT deposits in the Sichuan-Yunnan-Guizhou (SYG) Pb-Zn metallogenic domain, the Fule Pb-Zn
deposit is hosted in the Permian Yangxin Formation dolostone, which is the youngest ore-bearing strata in the area, and the distance
between Pb-Zn ore bodies and the Permian Emeishan basalts is less than 160 m. By means of microscopic, Scanning Electron
Microscopy (SEM) and Energy Dispersive Spectrum (EDS) analysis, a great number of copper-bearing minerals were found in the
deposit, including chalcopyrite, Zn-tennantite, tetrahedrite and malachite. These minerals occur as banded, vein and irregular, and
replace sphalerite or pyrite. The research shows that the droplet chalcopyrite is distributed within sphalerite, implying that both of themsphalerite grain, or distributed at the edge of the sphalerite, indicating that it was formed later than that of Pb-Zn mineralization. The
copper minerals mentioned in this study commonly occur in middle-low temperature hydrothermal deposits, in which the Zn-tennantite
is a rare sulfosalts. The appearance of Zn-tennantite and tetrahedrite indicates an oxidizing environment, and malachite is a secondary
mineral formed at supergene weathering stage. The paragenetic sequence in the deposit is inferred as follows: pyrite→sphalerite
(droplet chalcopyrite)→galena→chalcopyrite→Zn-tennantite→tetrahedrite→malachite. Combined with the geologic and geochemical
characteristics of this deposit, it is suggested that there are two possible sources of copper. Early-stage copper was derived mainly from
the basement of the Kunyang group and the late-stage copper was likely stemmed from the upper Emeishan basalts, which are different
from those of Pb and Zn derived mainly from the Kunyang Group in the deposit. The research provids new geological and geochemical
evidence for understanding the genetic relationship between the Emeishan basalts and Pb-Zn mineralization in the SYG district.

Key words: Fule Pb-Zn deposit, chalcopyrite, Zn-tennantite, tetrahedrite, MVT deposits