An Infrared Microscope Investigation of Fluid Inclusions in Coexisting Quartz and Wolframite: A Case Study of Yaogangxian Quartz-Vein Wolframite Deposit
In order to understand the differences between the fluid inclusions in ore minerals and those in gangue minerals, the authors performed a microthermometric study of fluid inclusions in wolframite and coexisting quartz from the Yaogangxian quartz-vein wolframite deposit by using infrared microscopy. The results show that homogeneous temperature (th) and salinity of fluid inclusions in quartz are obviously different from those in wolframite, in spite of the fact that these two minerals were formed at the same ore-forming stage. Combined with H, O isotope analyses and ore micro-texture features, the authors have drawn a conclusion that the fluids captured in wolframite were formed at an early stage when the solution was homogeneous, and the temperature declining was the main cause for mineral deposition, whereas the fluids in quartz had mixed fluid properties of igneous fluid and underground water, suggesting their formation at a later stage.