岩浆硫化物矿床研究现状及重要科学问题

Current research status and important issues of magmatic sulfide deposits

20世纪90年代,岩浆通道成矿模型的提出为岩浆硫化物矿床成因研究提供了崭新的思路,但对成矿机制和找矿标志的认识依然存在分歧。2000年以来,不同学者从岩浆通道形成的构造因素,外来硫加入的方式和控制因素,硫化物熔离、运移和沉降的热力学条件及动力学机制,区域找矿标志等方面对岩浆通道成矿机理进行了更深入的探讨。最近的研究发现,原来建立在热力学平衡假设基础上的一些认识需要纠正,硫化物熔离的化学动力学机制以及岩浆流体动力学状态对矿床的地质和地球化学特征具有不可忽视的影响,玄武岩铂族元素亏损的形成机制和找矿意义需要重新认识。

The ore-forming model in magma conduit proposed in 1990’s was a new approach for study of the formation of magmatic sulfide deposits. However, there still exists controversy concerning ore-forming mechanism and prospecting indicators. Since 2000, detailed studies of the formation of magmatic sulfide deposits in the magma conduit systems have been focused on structural factors controlling the formation of magma conduit, mechanism and factors governing input of external sulfur into the magma, thermodynamic conditions and dynamic mechanism of sulfide immiscibility, movement and segregation, and regional prospecting indicators. These new studies indicated that some insights based on equilibrium thermodynamics need to be modified corrected. The geological and geochemical features of magmatic sulfide deposits are significantly affected by kinetic mechanism of sulfide immiscibility as well as magma fluid dynamics. The mechanism of depletion of platinum-group elements in basalts and its prospecting significance should be reevaluated.