Facility Support: High-Resolution X-ray Computed Tomography Laboratory

1561622KetchamThis地球科学仪器和设施计划拨款部门支持德克萨斯大学计算机X射线断层扫描（UTCT）设施在两年内继续运作。UT的CT扫描仪专门设计用于对一系列地质材料和样本大小进行X射线断层扫描。该技术是从商业生物医学CAT扫描仪发展而来的，采用了更高能量的X射线源和更高分辨率的CCD探测器，可以对地质样品进行微米级成像。该技术允许对样品的外部和内部进行完全非破坏性成像。由于样品密度和材料元素成分沿X射线路径沿着的变化而产生的X射线衰减差异由CCD数字化记录。将样品安装在X射线源前面的旋转台上。衰减x射线的径向2-d切片通过样品台的垂直平移来堆叠。然后，通过计算机算法减少所得的X射线正弦图，以呈现样品内密度分布的高分辨率3-D图像。UTCT高能系统最近的升级提高了分辨率和扫描速度，降低了实验室客户的成本，并开辟了许多新的研究可能性。特别是，它能够对运动中的系统进行4-D扫描（在流体流动、冷却、加热、应变等过程中）。通过这一续签合同，将能够探索和利用这些新的能力，扩大研究范围，包括与地下水水文学、油气藏开采增强和二氧化碳地下封存相关的通过裂隙和多孔介质的流体流动研究。持续的支持将使大量不同的研究群体受益。在过去的支持期间，UTCT已为190多名主要研究人员提供服务，其中大多数是地球科学家，涵盖了岩石学，古生物学，构造地质学，水文学，气象学以及经济和石油地质学。UTCT的客户还包括许多其他领域的研究人员，主要是生物学，工程学和人类学。四分之三的调查人员来自德克萨斯大学以外。该设施将继续通过开发的短期课程支持用户培训，并协助用户进行数据简化程序。 这种支持与NSF促进科学进步的使命是一致的，并且可以通过提高对地下水和碳氢化合物行为的认识以及培训学生掌握科学中的尖端分析方法来促进国家的繁荣和福利。

1561622KetchamThis Division of Earth Sciences Instrumentation and Facilities Program grant supports continued operation of the University of Texas Computed X-ray Tomography (UTCT) Facility over a two year period. The CT scanner at UT was specifically designed to enable x-ray tomography of a range of geological materials and sample sizes. The technology was developed from commercial biomedical CAT scanners with the adoption of a higher energy x-ray source and higher resolution CCD detectors to allow micron-scale imaging of geological samples. The technique allows for completely non-destructive imaging of the exteriors and interiors of samples. Differences in x-ray attenuation that occur due to variations in sample density and the elemental composition of the material along the x-ray path are digitally recorded by a CCD. Samples are mounted on a rotating table in front of the x-ray source. Radial 2-d slices of the attenuated x-rays are stacked by vertical translation of the sample table. Resultant x-ray sinograms are then reduced via computer algorithms to render high resolution 3-D images of the density distributions within samples. A recent upgrade of the UTCT high energy system has increased both resolution and scanning speed, lowering costs for lab clients and opened a multitude of new research possibilities. In particular, it enables 4-D scanning of systems in motion (during fluid flow, cooling, heating, strain, etc.). Exploration and exploitation of these new capabilities for an expanded range of studies including studies of fluid flow through fractured and porous media with relevance to groundwater hydrology, hydrocarbon reservoir extraction enhancement and carbon dioxide subsurface sequestration will be enabled by this renewal award. Continued support will benefit a large and diverse set of research constituencies. Over the previous period of support, UTCT has served over 190 principal investigators, most of whom are Earth scientists spanning the full breadth of subdisciplines, including petrology, paleontology, structural geology, hydrology, meteoritics, and economic and petroleum geology. UTCT's clientele also includes many researchers in other fields, principally biology, engineering, and anthropology. Three-quarters of investigators were from outside the University of Texas. The facility will continue to support user training through developed short courses and assist users in data reduction routines. This support is congruent with NSFs mission of promoting the progress of science and may advance the national prosperity and welfare through advancing knowledge of the behavior of water and hydrocarbon in the subsurface as well training students in cutting edge analytical methods in the sciences.***