Implications of the structural setting, magma-wallrock interaction and postemplacement evolution of postorogenic carbonatites for their rare-metal (REE, Nb, Zr, U) potential

碳酸盐岩及其成因岩是稀有金属的重要经济来源。近年来，人们越来越认识到碳酸盐岩可能有多种成因，并根据其构造环境和地幔来源表现出根本的差异。这些岩石成因与碳酸盐岩地球化学之间的关系至今尚未得到系统的研究。虽然已经认识到一些碳酸盐岩与造山作用有关，但目前对这种岩浆作用的成因和矿物潜力都不了解。碳酸盐岩岩石学的其他未充分研究的方面是岩浆-围岩相互作用对稀有金属（稀土元素，Nb, Ta， Zr和U）的输运和封存的影响，以及就位后过程对碳酸盐岩承载矿体的几何形状和组成的影响。拟议的研究计划将解决这些现有的知识差距，试图确定有助于在造山带碳酸盐岩中开发可采稀有金属经济浓度的主要因素。该计划的新颖之处在于，它将涉及不同时代造山带的碳酸盐岩的系统研究及其在构造和构造背景下的成岩和成矿分析。该项目将基于申请人对这些岩石的丰富经验，以及他与加拿大、俄罗斯、中国、摩洛哥和欧盟科学家的持续合作。这项研究将包括一个大的训练组成部分，并将以多分析方法为基础，以确保在碳酸盐岩演化的背景下可以解释不同类型的矿化。这项工作的三个主要成果将是：(1)提高对形成后碳酸盐岩的来源和形成过程的认识；(2)完善这些岩石所含矿床的勘查标准；(3)培养具有稀有金属勘查专业知识和现场实践知识和仪器技术的高素质人才。马尼托巴大学在提供这类培训方面具有独特的工具性能力。

Carbonatites and genetically related rocks are an economically important source of rare metals. In recent years, it has been increasingly recognized that carbonatites may have multiple origins and show fundamental differences specific to their tectonic setting and mantle sources. These relations between the petrogenesis and geochemistry of carbonatites have not been systematically studied to date. Although it has been recognized that some carbonatites are linked to orogenic processes, neither the causes nor mineral potential of this magmatism are presently understood. Other inadequately studied aspects of carbonatite petrology are the effect of magma-wallrock interaction on the transport and sequestration of rare metals (rare-earth elements, Nb, Ta, Zr and U), and the impact of postemplacement processes on the geometry and composition of ore bodies hosted by carbonatites. The proposed research program will address these existing knowledge gaps in an attempt to identify the principal factors that contribute to the development of recoverable economic concentrations of rare metals in carbonatites situated in orogenic settings. The novelty of the proposed program in that it will involve a systematic study of carbonatites from orogenic systems of different age and their petrogenetic and metallogenic analysis in a tectonic and structural context. The program will build on applicant's extensive experience with these rocks and his ongoing collaboration with scientists in Canada, Russia, China, Morocco and the European Union. This research will include a large training component and will be based on a multi-analytical approach to ensure that different styles of mineralization can be interpreted in the context of carbonatite evolution. The three major outcomes of this work will be: (1) an improved understanding of the sources and processes responsible for the formation of postorogenic carbonatites; (2) refined exploration criteria for ore deposits hosted by these rocks, and (3) training of highly qualified personnel with a know-how in rare-metal exploration and practical knowledge of field and instrumental techniques. The University of Manitoba has unique instrumental capabilities for providing this type of training.