Acquisition of a Scanning Electron Microscope at Yale Geology and Geophysics

0216784 Karato该合同将允许购买一台扫描电子显微镜（SEM），该显微镜具有一系列高分辨率分析地球材料（包括生物样品）结构和成分的能力。 我们将购买的扫描电镜是Philips XL 30 ESEM-FEG，它可在低真空和高真空模式下工作，配有场发射枪（FEG）和用于电子背散射衍射（EBSD）图案分析的软件/硬件包。这一新设施对耶鲁地质学和地球物理学的各种研究活动至关重要，包括：（1）实验和自然变形样品的变形微观结构（Karato，布兰登），（2）流体-岩石相互作用（Ague，Rye），（3）微生物地球化学和地质微生物学（布莱克）。 由附在这种最先进的SEM上的EBSD包提供的具有高空间分辨率的完整方位测量对于Karato和布兰登对变形岩石的显微结构研究至关重要。 这种技术的地质应用在欧洲很普遍，但仅限于美国的少数实验室。 当FEG电子源与EBSD封装一起使用时，取向测量的空间分辨率接近0.25 mm。如此高的空间分辨率是至关重要的，特别是对于Karato小组的实验研究，其中使用具有非常细的晶粒尺寸的试样研究高压条件下的微观结构发展。同样，ESEM的操作模式在耶鲁地质学和地球物理学的几个研究领域具有重大优势。 这包括通过电荷对比成像技术（选择性地在ESEM模式下工作）研究流体与岩石的相互作用，以及微生物地球化学和地球微生物学的研究，这需要矿物表面形态和相关形态的高分辨率图像。微生物。 在现有分析和其他实验设施的基础上增加这一设施，将大大加强耶鲁大学地质学和地球物理学系的实验地球科学研究方案。

0216784KaratoThis award will permit the purchase of a scanning electron microscope (SEM) with a range of capabilities for high-resolution analyses of structures and compositions of Earth materials, including biological samples. The SEM we will purchase is a Philips XL30 ESEM-FEG, which operates with both low- and high-vacuum modes with a field emission gun (FEG) and a software/hardware package for an electron backscattered diffraction (EBSD) pattern analysis. This new facility is critical to the diverse research activities at Yale Geology and Geophysics including studies of: (1) deformation microstructures of experimentally and naturally deformed samples (Karato, Brandon), (2) fluid-rock interaction (Ague, Rye), (3) microbial geochemistry and geomicrobiology (Blake). Complete orientation measurements with high-spatial resolution, as provided by the EBSD package attached to this type of state-of-the-art SEM, are critical to microstructural studies on deformed rocks by Karato and Brandon. Geologic application of this technique is widespread in Europe, but has been limited to only a handful of labs in the United States. The spatial resolution of orientation measurements is close to 0.25 mm when the FEG electron source is used with an EBSD package. Such a high spatial resolution is critical, particularly for the experimental studies in Karato's group where microstructural developments under high-pressure conditions are studied using specimens with very fine grain size. Similarly, the ESEM mode of operation of this SEM has major advantages in several research areas at Yale Geology and Geophysics. This includes the study of fluid-rock interaction through the charge-contrast imaging technique (which works selectively at ESEM mode), and the study of microbial geochemistry and geomicrobiology, which requires high-resolution images of the morphology of mineral surfaces and associated microorganisms. Addition of this facility to the existing analytical and other experimental facilities will significantly enhance the research programs of experimental Earth science at the department of Geology and Geophysics at Yale University.***