The Jibote iron deposit is a typical example of iron deposit hosted in submarine volcanic-sedimentary assemblages and located in the Maizi volcano-sedimentary basin in the southern margin of the Chinese Altay orogenic belt (AOB). The ore bodies are interbedded with the Upper Silurian to Lower Devonian metamorphosed volcanic-sedimentary rocks and display same distortion as wall rocks, which is always associated with intensely skarn alteration. In this research, detailed inclusion studies are carried out on skarn minerals (garnet, diopside and epidote), quartz and calcite. Abundant inclusions have been observed in garnets including melt inclusions, fluid-melt inclusions and fluid inclusions, while fluid inclusions are only occurred in other minerals. These inclusions were studied using microthermometry, laser Raman spectroscopy and EMPA. The coexistence of melt inclusions with simultaneously trapped fluid-melt inclusions and fluid inclusions suggests immiscibility between silicate melt and hydrothermal fluid (magmatic fluids exsolved). Melt inclusions contain abundant Fe-rich melt and silica-rich glasses, displaying strong evidence for melt immiscibility which plays a key role in the mineralization. Quartz, fluorite, magnetite and calcite occur at various inclusions and as solid in garnet suggest they are formed by crystallization fractionation from magma melt. Laser Raman experiments reveal H2O as the dominant volatile compounds in the melt inclusions in garnet and CO2 in fluid inclusions in quartz. Inclusions features support a magmatic origin for the Jibote iron deposit and magmatism, magmatic hydrothermal fluids and skarn alteration constraint on metallic ore formation.
Wang Wen Chai Fengmei Wang Haipei Yang Junjie Li Qiang Gu Gaoling . Inclusions study of Jibote iron deposit in the Chinese Altay orogenic belt：Evidence of magmatic in origin[J]. Chinese Journal of Geology, 2017, 52(2): 571-591.