Electron-probe microanalyzer (EPMA) for geomaterials research

电子探针显微分析(EPMA)是地球科学中广泛采用的一种空间分辨分析固相(矿物、熔体包裹体)化学成分的方法。结合使用EPMA和激光消融电感耦合等离子体质谱(LA-ICPMS)对矿物进行主量元素和微量元素分析，使我们对地壳流体流动过程和世界级热液金属矿床的形成过程有了全新的认识，这一点从我们在地球流体和地质材料研究方面的记录中就可以看出。因此，我们申请资助新一代电子探针仪器，配备大大改进的WDS光谱仪，为高精度分析复杂矿物的主要元素组成和低浓度分析水合硅酸盐和磷酸盐中的卤素(F，Cl)开辟了新的可能性，这些都是热液过程的关键示踪剂。新的EPMA将取代已有20多年历史的仪器，该仪器越来越多地受到技术问题、延长的停机时间以及不断上涨的维护和维修成本的影响。新的EPMA将由RWTH亚琛大学的4个研究小组组成的联盟使用，它们是应用矿物学和经济地质学、结晶学、地质学和矿产资源工程小组。新的EPMA仪器将使开展地质材料和地球流体的前沿研究成为可能，包括地壳流体中卤素的来源和分配、世界级热液和岩浆热液金属矿床的形成、变质作用和地壳岩石部分熔融过程中流体和金属的产生和迁移、主要沉积盆地的成岩演化、盐类矿床变形和活化的化学效应、关键金属在新型矿床中的分布以及稀土和锆相的化学性质和物理性质之间的联系。

Electron-probe microanalysis (EPMA) is a widely established method for spatially resolved analysis of the chemical composition of solid phases (minerals, melt inclusions) in the Earth Sciences. Combining major and trace element analysis of minerals using EPMA and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has resulted in fundamentally new insight into the processes of crustal fluid flow and formation of world-class hydrothermal metal ore deposits, as demonstrated by our track record in geofluids and geomaterials research. We therefore apply for funding for a next-generation EPMA instrument equipped with greatly improved WDS spectrometers that opens up new possibilities for high-precision analysis of the major element composition of complex minerals and low-concentration analysis of halogens (F, Cl) in hydrous silicates and phosphates, which are key tracers of hydrothermal processes. The new EPMA will replace a more than 20 years old instrument, which is increasingly affected by technical problems, extended downtimes and continuously rising costs for maintenance and repair. The new EPMA will be used by a consortium of 4 research groups at RWTH Aachen University, which are the Applied Mineralogy and Economic Geology, Crystallography, Geology and Mineral Resources Engineering groups. The new EPMA instrument will make it possible to perform frontier research in geomaterials and geofluids, including the sources and partitioning of halogens in crustal fluids, the formation of world-class hydrothermal and magmatic-hydrothermal metal ore deposits, the production and migration of fluids and metals during metamorphism and partial melting of crustal rocks, the diagenetic evolution of major sedimentary basins, the chemical effect of deformation and mobilization of salt deposits, the distribution of critical metals in new types of ore deposits, and the link between chemistry and physical properties of REE and Zr phases.