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金伯利岩是研究地幔动力学过程、探讨岩石圈演化等深部重大科学问题的有效载体,也是揭示金刚石这一稀缺矿产资源的形成环境、成因、来源及找矿实践等最为重要的研究对象之一。长期以来,由于受到研究手段、研究思路等的限制,对金伯利岩相关研究的核心与瓶颈性关键基础科学问题,即“金伯利岩的初始岩浆组成”、“金伯利岩的演化过程及其意义”、“金伯利岩的金刚石含矿性评价”等知之甚少,这极大地制约了人们对金伯利岩及其相关深部过程意义等方面的深入了解。例如,基于高压熔体模拟实验、基质矿物、细小同源包裹体及金伯利岩筒边部隐晶质物质的研究,可以有效分析金伯利质岩浆的初始组成特征,但却难于有效甄别金伯利质岩浆的源区特征,难于有效区分地幔同化/混染作用、流体分异以及就位期间的脱玻化作用等对岩浆的影响等;由于缺乏再结晶及(或)再生长矿物在微成分、微结构方面的系统研究报道,难于有效精准分析金伯利质岩浆组成的变化规律及脱气作用的影响,揭示金伯利质岩浆的演化过程;尽管根据共生矿物组合、橄榄石的含水性等可用于评估金伯利岩的金刚石含矿性,但存在指标体系过于简单、数据积累少等方面问题。理论上,从微区(微米级、纳米级)的角度,对金伯利岩各组成结构单元中矿物等的微成份、微结构进行系统研究,可以更为精准地提取金伯利质初始岩浆组成、演化过程等方面的信息,因此对含金刚石与不含金刚石的金伯利岩的微组构进行精细研究,可以为有效重建金伯利质岩浆的演化机制、深入揭示其对深部过程的响应等奠定科学基础。同时,也可以在对已知金刚石矿区研究的基础上,建立用于金刚石初始品位预测和保存潜力分析的模型,以实现有效评价未知金伯利岩区的含矿性的目的。
The kimberlite is an effective carrier for studying the dynamics of the mantle and exploring major scientific issues such as the evolution of the lithosphere. It is also one of the most important research subjects to reveal the formation environment, causes, sources and prospecting practices of this scarce mineral resource. For a long time, due to limitations of research methods, research ideas and other limitations, the key basic scientific questions concerning the core and bottleneck of kimberlite related research are: “the initial magmatic composition of kimberlite”, “the evolution of kimberlite and its Significance, ”“ little knowledge about diamond mineralization in kimberlites, ”which greatly restricted people’s in-depth understanding of the significance of kimberlite and its related deep processes. For example, based on high-pressure melt simulation experiments, studies of matrix minerals, fine homogenous inclusions and aphanotrophic materials on the edge of kimberlite can effectively analyze the initial compositional features of kimberlite magma, but it is difficult to effectively identify kimberlite magma Source zone characteristics, it is difficult to effectively distinguish between mantle assimilation / contamination effect, fluid differentiation, and devitrification during the in-situ magma, etc. Due to the lack of recrystallization and / or re-growth of minerals in the micro-components It is difficult to effectively and accurately analyze the variation of kimberlite magma composition and the effect of degassing to reveal the evolution of kimberlite magma. Although the water content of olivine can be used to evaluate the kimberlite according to the symbiotic mineral assemblage Diamond ore, but there are indicators of the system is too simple, less data accumulation and other issues. Theoretically, the micro-components and microstructures of the kimberlite structural elements in the microstructure (microscale, nanoscale) are studied systematically, which can extract the initial magma composition and evolution process of the kimberlite more precisely Therefore, a detailed study on the microstructure of diamond-bearing and diamond-free kimberlites can provide a scientific basis for effectively reconstructing the evolution mechanism of kimberlite magma and revealing its response to deep processes. At the same time, based on the study of known diamond mining areas, a model for the initial grade prediction and preservation potential analysis of diamonds can also be established in order to achieve the purpose of effectively evaluating the ore-bearing of unknown kimberlite areas.