Field Emission Scanning Electron Microscope with EBSD, EDS and CL

对于地球动力学组以及其他地球科学和土壤科学工作组的研究，马丁-路德-哈勒-维滕贝格大学（MLU）自然科学第三学院的岩石和地质材料的结构，晶体取向和化学成分的分析是必不可少的。科学问题需要在厘米到亚微米范围内的分析能力。扫描电子显微镜（SEM）允许在这个尺寸范围内研究表面和相衬。矿物相的晶体取向由EBSD（电子背散射衍射）探测器测量。化学分析是由EDS（能量色散x射线光谱）探测器进行的。用CL（阴极发光）检测器对晶体缺陷和微量元素的分带和分布进行了成像。计划进行的至少五个数量级（厘米到亚微米范围）的调查需要高空间分辨率和快速测量，以便能够对大样本区域进行映射。为此，肖特基场发射扫描电子显微镜（FEG-SEM）是必不可少的，因为它提供了所需的光束参数和光束稳定性。FEG-SEM将主要用于分析岩石中的变形结构。研究范围从上地壳的纳米级地震过程到岩石中剪切带的发展，其中含有高达毫米级的矿物颗粒，因为它们发生在地球下地壳和地幔中。对于压裂、摩擦滑动或粘性蠕变等微观或纳米力学过程的研究，需要高分辨率成像技术、晶体学测量和SEM分析的化学结果。除了这些研究有助于提高我们对板块构造过程和地震成核的理解外，新的仪器还可以量化矿物颗粒的分布和方向，以确定各种岩石和地质材料的物理和化学性质。这对于地球物理和地震研究或天然石材制造、隧道建设、地热能、最终废物处理、陶瓷和胶结研究以及有关应用地质学、矿床勘探和技术矿物学的进一步主题的技术应用非常重要。除了广泛的地球科学研究目标之外，新仪器还需要用于MLU的土壤科学研究。主要研究受风化、各种环境因素和气候变化影响的土壤矿物质与有机质的相互作用。

For the research of the Geodynamics group as well as the other geoscientific and soil scientific working groups of the Faculty of Natural Sciences III of the Martin-Luther-University Halle-Wittenberg (MLU) the analysis of structure, crystallographic orientation and chemical composition of rocks and geomaterials is essential. The scientific problems require analysis capabilities in the range of centimeters to sub-micrometers. A scanning electron microscope (SEM) allows for the investigation of surface and phase contrast in this size range. Crystallographic orientations of the mineral phases are measured by an EBSD (Electron backscatter diffraction) detector. The chemical analysis is carried out by an EDS (Energy dispersive X-ray spectroscopy) detector. Zonations as well as the distribution of trace elements and crystal defects are imaged by a CL (Cathodoluminescence) detector. The planned investigations over at least five orders of magnitude (range of centimeters to sub-micrometers) necessitate both a high spatial resolution and also fast measurements in order to enable mappings of large sample areas. For that, a Schottky field emission scanning electron microscope (FEG-SEM) is indispensable as it provides the required beam parameters and beam stability.The FEG-SEM will primarily be used for the analysis of deformation fabrics in rocks. The spectrum of investigations ranges from nanoscale earthquake processes in the upper crust to the development of shear zones in rocks with up to millimeter-scale mineral grains as they occur in the lower crust and mantle of the Earth. For the research on the micro- or rather nano-mechanical processes of fracturing, frictional sliding or viscous creep high-resolution imaging techniques, crystallographic measurements and chemical results of the SEM analysis are necessary. Apart from these investigations that help to improve our understanding of plate tectonic processes and also earthquake nucleation, the new instrument shall be used to quantify the distribution and orientation of mineral grains to determine the physical and chemical properties of various rocks and geomaterials. This is important for geophysical and seismic studies or for technical applications of natural stone manufacture, tunnel construction, geothermal energy, ultimate waste disposal, ceramic and cementitious research as well as further topics concerning applied geology, mineral deposit exploration and technical mineralogy. Beside the wide field of geoscientific research goals the new instrument is also needed for soil scientific research at the MLU. Main topics are interactions between soil minerals and organic matter influenced by weathering, various environmental factors and climate change.