X-ray Diffractometer with micro diffraction

要深入了解地壳上部复杂的矿物-水相互作用过程和元素环境行为的可预测性，就需要阐明流体/固体界面上的个别反应机制。对这些机制的定量评估是柏林理工大学应用地球化学组的中心研究目标。这种研究方法反过来又需要使用现代光谱和显微方法。除了常规的实验室方法外，还使用了最先进的同步加速器方法。作为柏林工业大学现有分析基础设施的补充，将建立一个微相分析实验室，该实验室可以定量表征矿物相及其化学成分，包括以高空间分辨率和低检测下限的痕量元素和同位素特征，并确定流体中的微量元素含量。该实验室应由三个主要部分组成：1)高性能X射线衍射仪和显微衍射仪(μX射线衍射仪)，识别粉末样品中的矿物相并在抛光矿物/岩石切片上进行空间分解。2)强大的μ-Focus X射线荧光分析(μXRF)，可以无损和高空间分辨率地量化岩土材料的化学成分。3)强大的激光电感耦合等离子体质谱仪(LA-ICPMS)，它能够对岩土材料进行高分辨率的微量元素分析，未来的研究项目将集中在以下领域的矿物/水相互作用过程：(I)地热系统；(Ii)污染物在所谓的临界区的迁移、转化和滞留；(Iii)古气候重建。

An in-depth understanding of the complex mineral-water interaction processes in the upper earth's crust and a predictability of the environmental behavior of elements requires the elucidation of individual reaction mechanisms at the fluid/solid interface. The quantitative assessment of these mechanisms is a central research goal of the Applied Geochemistry Group at TU Berlin. This research approach in turn requires the use of modern spectroscopic and microscopic methods. In addition to conventional laboratory methods, state-of-the-art synchrotron-based methods are also used.Complementary to the existing analytical infrastructure of the TU Berlin, a laboratory for microphase analysis will be set up, which offers the possibilities to quantitatively characterize mineral phases and their chemical composition, including trace elements and isotope signatures in high spatial resolution with low detection limits and to determine trace element contents of fluids. The laboratory should consist of three main components:1) High-performance X-ray diffractometry with micro diffraction (μXRD) that identifies mineral phases both in powder samples and spatially resolved on polished mineral/rock sections.2) A powerful X-ray fluorescence analysis with μ-focus (μXRF), with which it is possible to quantify the chemical composition of geomaterials nondestructively and in high spatial resolution.3) A powerful Laser ICP Mass Spectrometer (LA-ICP-MS), which enables a high-resolution trace element analysis of geomaterials, determines isotope ratios of selected elements and can be used for the trace element analysis of water samples.Future research projects in which the micro techniques will be used focus on mineral/water interaction processes in the following areas: (i) geothermal energy systems, (ii) transport, transformation and retention of pollutants in the so-called critical zone, (iii) paleoclimate reconstruction.